introduction of machinery--suffered materially in the latter part of

the last century through the bitter rivalry of machinery manufacturers, a common process being the enjoining of manufacturers from the use of machines on which it was claimed the patents were infringed and this created a state of great uncertainty in the minds of many of those manufacturing shoes. This condition finally found its solution in the formation of one large corporation, known in the shoe industry as the “United Shoe Machinery Company,” which purchased the patents for a sufficient number of machines to form a complete system for the “bottoming”--or fastening the soles and heels of shoes--and finishing them. These machines have been the subject of constant improvement and others have been perfected to take care of operations which, prior to their introduction, were purely hand operations. Each machine has been standardized and so adapted to meet the requirements of those used in connection with it that they collectively form the most remarkable and efficient system of machines used at the present time. Mention is made of this company owing to the important position it has taken in the organization and advancement of the industry, the American-made shoe being the one commodity of world-wide consumption whose supremacy is not contested. [Illustration: MY LADY’S SLIPPERS OF EARLY TIMES EMBROIDERED RIDING BOOT WORN BY NOBLES DURING LAST DAYS OF POLISH INDEPENDENCE] [Illustration: EMBROIDERED RIDING BOOT FROM PERSIA OF ABOUT 1850] [Illustration: FRENCH CALF BOOT MADE IN NEW YORK CITY, 1835] [Illustration: LADY’S SHOE--PERIOD OF THE FRENCH REVOLUTION] [Illustration: LADY’S SHOE--PERIOD OF LOUIS XVI. Has wooden heel.] [Illustration: LADY’S ADELAID OR SIDE LACED SHOE--PERIOD 1830 TO 1870] [Illustration: CHANNEL LIP CROSS-SECTION OF INSOLE WOODEN LAST—DETERMINES SIZE AND SHAPE OF SHOE AN INSOLE AN INSOLE TACKED TO BOTTOM OF LAST THE BEGINNING OF A SHOE] How Shoes Are Made by Machinery At the present time the types of shoes ordinarily made are but five: the “peg” shoe, which is the cheapest type of shoe made; the “standard screw,” which is used in the soles of the heaviest types of boots; the “McKay sewed,” which is made after the fashion established by Gordon McKay; the “turn” shoe, a light type of shoe which was invented centuries ago and which is still worn at this time to a limited extent; and the “Goodyear welt,” which has been universally adopted as the highest type of footwear. For this reason, this type of shoe has been selected to show the methods employed in making shoes. THE GOODYEAR WELT SHOE.--A Goodyear Welt shoe in its evolution from the embryonic state in which it is “mere leather and thread” to the completed product, passes through one hundred and six different pairs of hands and is obliged to conform to the requirements of fifty-eight different machines, each performing with unyielding accuracy the various operations for which they were designed. It might seem that in all this multiplicity of operations confusion would occur, and that the many details and specifications regarding material and design of any given lot of shoes in process of manufacture would become hopelessly entangled with those of similar lots undergoing the same operations. But such is not the case; for, when an order is received in any modern and well-organized factory, the factory management promptly take the precaution to see that all the details regarding the samples to which the finished product is to conform are set down in the order book. Each lot is given an order number and this number, together with the details affecting the preparation of the shoe upper, are written on tags--one for each two dozen shoes--which are sent to the foreman of the cutting room. Others containing details regarding the sole leather are sent to the sole leather room, while a third lot is made out for the guidance of the foreman of the making or bottoming room, when the different parts which have received attention and been prepared according to specifications in the cutting and sole leather rooms are ready to be assembled for the making or bottoming process. If the tags which were sent to the cutting room were followed, it would be found that on their receipt the foreman of this department figured out the amount and kind of leather required, the kind of linings, stays, etc., and that the leather, together with the tags which gave directions regarding the size, etc., was sent to one of the operators of the Ideal Clicking Machine. ~SHOEMAKING MACHINERY IS ALL BUT HUMAN~ This machine has been pronounced one of the most important innovations that have been made in the shoe manufacturing industry during recent years, as it performs an operation which has heretofore successfully withstood every attempt at mechanical aid. Prior to its introduction, the cutting of upper leather was accomplished by the use of patterns made with metal edges, which were laid upon the leather by cutter, who then ran a small sharp knife along the edges of the pattern, cutting the leather to conform to it. This was a slow and laborious process, and if great care was not taken, there was a tendency to cut away from the pattern; and in many cases, through some slip of the knife, the leather was cut beyond the required limits. This machine has a cutting board very similar to those which were used by the hand workman and over it is a beam which can be swung either to the right or to the left, as desired, and over any portion of the board. Any kind of skin to be cut is placed on the board, and the operator places a die of unusual design on it. Grasping the handle, which is a part of the swinging beam, he swings the beam over the die, and on downward pressure of the handle a clutch is engaged which brings the beam downward, pressing the die through the leather. As soon as this is accomplished, the beam automatically returns to its full height and remains there until the handle is again pressed. The dies used are but three-quarters of an inch in height and are so light that they do not mar the most delicate leather when placed upon it. They enable the operator to see clearly the entire surface of the leather he is cutting out, and it is obvious that the pieces cut by the use of any given die must be identically the same. After the different parts required by the tag have been cut out by the operator of the Clicking Machine, some of the edges which show in the finished shoe must be skived or thinned down to a beveled edge. This work is performed by the Amazeen Skiving Machine--a wonderful little machine in which the edge to be skived is fed to a sharp revolving disk that cuts it down to the desired bevel. The machine does the work in a very efficient manner, conforming to all the curves and angles. This skiving is done in order that the edges may be folded, to give the particular edge on which it is performed a more finished appearance. The skived edges are then given a little coating of cement and afterwards folded on a machine which turns back the edge and incidentally pounds it down, so that it presents a very smooth and finished appearance. Aside from the work of skiving toe caps and folding them, there is generally a series of ornamental perforations cut along the edge of the cap. This is done very often by the Power Tip Press, by means of which the piece to be perforated is placed under a series of dies which cuts the perforations in the leather according to a predetermined design, doing the work all at one time. The number of designs used for this purpose are many and varied, combinations of different sized perforations being worked out in innumerable designs. On one of the top linings of each shoe there has been stamped the order number, together with the size of the shoe for which the linings were intended. After all the linings have been prepared in accordance with the instructions on the tag, they, in connection with the various parts of the shoe, receive attention from the Stitchers, where all the different parts of the upper are united. The work is performed on a range of wonderful machines, which perform all the different operations with great rapidity and accuracy. At the completion of these operations the shoe is ready to receive the eyelets, which are placed with remarkable speed and accuracy by the Duplex Eyeletting Machine. This machine eyelets both sides of the shoe at one time with bewildering rapidity. The eyelets are securely placed and accurately spaced; and as both sides of the upper are eyeletted at one time, the eyelets are placed directly opposite each other, which greatly helps the fitting of the shoe, as thereby the wrinkling of the shoe upper is avoided. With the completion of this operation, the preparation of the shoe upper is finished, and the different lots with their tags are sent to the bottoming room to await the coming of the different sole leather portions of the shoe. These have been undergoing preparation in the sole leather room, where on receipt of tag the foreman has given directions for the preparation of outsoles, insoles, counters, toe boxes and heels, to conform with the requirements of the order. The soles are roughly died out from sides of sole leather on large Dieing-out Machines, which press heavy dies down through the leather; but to make them conform exactly to the required shape, they are generally rounded out on a machine known as the “Planet Rounding Machine,” in which the roughly died-out piece of leather is held between clamps, one of which is the exact pattern of the sole. On starting the machine, a little knife darts around this pattern, cutting the sole exactly to conform with it. The outsole is now passed to a heavy Rolling Machine, where it is subjected to tons of pressure between heavy rolls. This takes the place of the hammering which the old-time shoemaker gave his leather and brings the fibres very closely together, greatly increasing its wear. This sole is next fed to a machine called the “Summit Splitting Machine--Model M,” which reduces it to an exactly even thickness. The insole--which is made of very much lighter leather--is prepared in much the same manner, and in this way it will be noticed that both the insole and outsole are reduced to an absolutely uniform thickness. The insole also receives further preparation; it is channeled on the Goodyear Channeling Machine. This machine cuts a little slit along the edge of the insole, extending about one-half inch towards its center. It also cuts a small channel along the surface. The lip which has been formed by the Goodyear Channeling Machine is now turned up on the Goodyear Lip Turning Machine, so that it extends out at a right angle from the insole, forming a lip or shoulder against which the welt is sewed. The cut which has been made on the surface inside this lip serves as a guide for the operator of the Welt Sewing Machine, when the shoe reaches that stage. The heels to be used on these shoes have also been formed from different lifts of leather which are cemented together. The heel is then placed under great pressure, giving it exact form and greatly increasing its wear. ~THE DIFFERENT PARTS OF THE SHOE COME TOGETHER~ The counters are also prepared in this room, as well as the toe boxes or stiffening, which is placed between the toe cap and the vamp of the shoe. When these are all completed, they are sent to the making or bottoming room, where the completed shoe upper is awaiting them. Here a wonderfully ingenious little machine called the “Ensign Lacing Machine,” passes strong twine through the eyelets and in a twinkling ties it automatically. This is done so that all parts of the shoe will be held in their normal position while the shoe is being made. The knot tied by this machine is perfect and is performed with mechanical exactness. On high-grade shoes this work was formerly performed by hand and it will be readily recognized how difficult it was to obtain uniformity. The spread of the upper at the throat can be regulated perfectly when this machine is used. The different parts of the shoe now commence to come together. The workman places the toe box, or stiffening, in the proper location as well as the counter at the heel, and draws the upper over the last. To the bottom of this last has already been tacked by means of the U. S. M. Co. Insole Tacking Machine--which drives tacks automatically--the insole, which, it will be noticed, conforms exactly to the shape of the bottom of the last. This last, made of wood, is of the utmost importance, for upon the last depends the shape of the shoe. [Illustration: EACH SHOE MACHINE DOES SOMETHING DIFFERENT ASSEMBLING MACHINE Operator locates back seam of upper on last. Machine drives two tacks which hold it in place.] The shoe as completed up to this point with the parts mentioned fastened together as shown, is now ready for assembling. The workman, after placing the last inside the shoe upper, puts it on the spindle of the Rex Assembling Machine, where he takes care that the seam at the heel is properly located. He presses a foot lever and a small tack is driven part way in, to hold the upper in place. He then hands it over to the operator of the Rex Pulling-Over Machine. [Illustration: PULLING-OVER MACHINE Draws shoe upper smoothly down to last. Operator adjusts it so that each seam occupies correct position on last. Machine automatically drives back to hold it in place.] This machine is a very important one; for as the parts of the shoe upper have been cut to exactly conform to the shape of the last, it is necessary that they should be correctly placed on the last to secure the desired results. The pincers of this machine grasp the leather at different points on each side of the toe; and the operator, standing in a position from which he can see when the upper is exactly centered, presses a foot lever, the pincers close and draw the leather securely against the wood of the last. At this point the operation of the machine halts. By moving different levers, the workman is able to adjust the shoe upper accurately, so that each part of it lies in the exact position it was intended when the shoe was designed. When this important operation has been completed, the operator again presses a foot lever, the pincers move toward each other, drawing the leather securely around the last, and at the same time there are driven automatically two tacks on each side and one at the toe, which hold the upper securely in position. These tacks are driven but part way in, so that they may be afterward removed. [Illustration: THE LASTING MACHINE ONE OF THE MOST IMPORTANT HAND METHOD LASTING MACHINE Last sides of shoe.] [Illustration: LASTING MACHINE Last toe and heel of shoe.] The shoe is now ready for lasting. This is one of the most difficult and important parts of the shoemaking process, for upon the success of this operation depends in a great measure the beauty and comfort of the shoe. The Consolidated Hand Method Welt Lasting Machine, which is used for this purpose, takes its name from the almost human way in which it performs this part of the work. It is wonderful to observe how evenly and tightly it draws the leather around the last. At each pull of the pincers a small tack driven automatically part way in holds the edge of the upper exactly in place, so that in the finished shoe every part of the upper has been stretched in all directions equally. The toe and heel of the shoe are considered particularly difficult portions to last properly. This important part of the work is now being very generally performed on the U. S. M. Co. Lasting Machine--No. 5, a machine of what is known as the “bed type.” It is provided with a series of wipers for toe and heel, which draw the leather simultaneously from all directions. There can be no wrinkles at the toe or heel of shoe on which it is properly used and the quality of work produced by it has been very generally recognized as a distinct advance in this important part of shoemaking. After the leather has been brought smoothly around the toe it is held there by a little tape fastened on each side of the toe and which is held securely in place by the surplus leather crimpled in at this point. The surplus leather crimpled in at the heel is forced smoothly down against the insole and held there by tacks driven by a very ingenious hand tool in which there is a constantly renewed supply of tacks. [Illustration: A MACHINE THAT FORMS AND DRIVES TACKS UPPER STAPLING MACHINE Forms small staples from wire. Holds shoe upper to lip of insole.] [Illustration: UPPER TRIMMING MACHINE. Trims off surplus part of shoe upper and lining.] In all of the lasting operations the tacks are driven but part way in, except at the heel portion of the shoe, where they are driven through the insole and clinched on the iron heel of the last. The tacks are driven only part way in, in order that they may be afterward withdrawn so as to leave the inside of the shoe perfectly smooth. In making shoes other than Goodyear Welts, with the exception of the Goodyear Turn Shoe, it is necessary to drive the tacks through the insole and clinch them inside the shoe, so that the different portions of the sole inside the shoe have clinched tacks. These are left even after the shoe is finished. This smooth interior of the shoe is one of the essential features of the Goodyear Welt Process. In the lasting operation there is naturally a surplus amount of leather left at the toe and sometimes around the sides of the shoe, and this is removed on the Rex Upper Trimming Machine in which a little knife cuts away the surplus portion of the leather very smoothly and evenly, and simultaneously a small hammer operating in connection with the knife pounds the leather smooth along the sides and the toe of the shoe. The shoe then passes to the Rex Pounding Machine, in which a hammer pounds the leather and counter around the heel so that the stiff portion of the shoe conforms exactly to the shape of the last. The shoe is now ready to receive the welt, which is a narrow strip of leather that is sewed along the edge of the shoe, beginning where the heel is placed and ending at the same spot on the opposite edge. This welt is sewed from the inside lip of the insole, so that the needle passes through the lip, upper and welt, uniting all three securely and allowing the welt to protrude evenly along the edge. The needle in making this stitch does not go inside the shoe, but passes through only a portion of the insole, leaving the inside perfectly smooth. This part of the work was formerly one of the most difficult and laborious tasks in shoemaking. As it was performed entirely by hand, the drawing of each stitch depended upon the strength and mood of the workman. It is of course obvious that with different operators stitches were oftentimes of different lengths and drawn at different tensions; for human nature is much the same everywhere, and it is impossible for a workman who has labored hard all day to draw a stitch with the same tension at night as might have been possible in the morning. [Illustration: AN AUTOMATIC SEWING MACHINE WHICH NEVER TIRES WELT AND TURNED SHOE SEWING MACHINE Upper portion shows operator at machine. The lower shows formation and location of stitch formed by this machine. Welt Stitch Welt] It is surprising how quickly and easily the work is done on the Goodyear Welt Sewing Machine. This famous machine has been the leading factor in the great revolution that has taken place in shoe manufacturing. Its work should be carefully noted--all stitches of equal length and measured automatically, the strong linen thread thoroughly waxed and drawn evenly and tightly; for the machine never tires, and it draws the thread as strongly in the evening as in the morning. Every completed movement of the needle forms a stitch of great strength, which holds the welt, upper and insole securely together. As the lasting tacks as well as the tacks which hold the insole in place on the last were withdrawn just prior to this operation, it will be seen that the inside of the shoe is left perfectly smooth. After this process the surplus portions of the lip, upper and welt which protrude beyond the stitches made by the Goodyear Welt Machine are trimmed off by the Goodyear Inseam Trimming Machine--a most efficient machine, in which a revolving cup-shaped knife comes in contact with the surplus portions of the leather and trims them off very smoothly down to the stitches. [Illustration: PUTTING THE GROUND CORK AND RUBBER CEMENT IN SHOES INSEAM TRIMMING MACHINE. Trims shoe upper lining and lip of insole smooth down to stitches.] [Illustration: WELT BEATING AND SLASHING MACHINE Beats welt so that it stands out evenly round edge of shoe.] [Illustration: PLACING SHANK AND FILLING BOTTOM. Workman tacks shank in place and fills bottom with ground cork and rubber cement.] At this stage the shoe is passed to the Universal Welt Beater, in which a little hammer vibrating very rapidly beats the welt so that it stands out evenly from the side of the shoe. As the leather is bent around the toe, it is the natural tendency of the welt to draw more tightly at that place, and this is taken care of by a little knife which the operator forces into operation, in the beating process, the toe is being taken care of, and it makes a series of little cuts diagonally along the edge of it. The insole and welt now receive a coating of rubber cement. This cement is contained in an air-tight tank and is applied by means of a revolving brush, which takes its supply of cement, as required, from a can. In this way, an even coating of any desired thickness is given to the insole and welt. This machine has many advantages; the cement being closely confined in the tank, there is almost no waste in its use. Formerly, when this was done by hand, the waste through evaporation or lack of care on the part of the workman was very material. The heavy outsole of the shoe also receives at this time proper attention. The flesh side of this sole, or the side next to the animal, receives a coating of rubber cement, and after it has dried slightly the operator of the Goodyear Improved Twin Sole Laying Machine takes the work in hand. In this machine there is a rubber pad, or mould, which has been made to conform to the curve in the sole of the shoe. After placing the last on the spindle, which is suspended from the machine and hangs over the rubber mould, the outsole having been previously pressed against the bottom of the shoe, the operator by pressing the foot lever causes this arm to descend, forcing the shoe down into the mould, so that every portion of the sole is pressed against the bottom of the shoe and welt. Here they are allowed to remain for a sufficient length of time for the cement to properly set, the operation being repeated on a duplicate part of the machine, the operator leaving one shoe under pressure while he is preparing another. [Illustration: MACHINES WHICH PUT THE SOLES ON SHOES SOLE LAYING MACHINE. Presses outsole to bottom of shoe where it is held by rubber cement.] [Illustration: ROUNDING AND CHANNELLING MACHINE. Roughly rounds outsole and welt to conform to shape of last. Cuts small channel along edge for stitches.] The next operation is that of trimming the sole and welt so that they will protrude a uniform distance from the edge of the shoe. This work is performed on the Goodyear Universal Rough Rounding Machine, which gauges the distance exactly from the edge of the last. It is often desired to have the edge extended further on the outside of the shoe than it does on the inside and also that the width of the edge should be considerably reduced in the shank of the shoe. This is taken care of with great accuracy by the use of this machine. The operator is able to change the width at will. By the use of this remarkable machine the operator is also enabled to make the sole of the shoe conform exactly to all others of similar size and design. [Illustration: CHANNEL OPENING MACHINE. Turns back lip of channel preparatory to stitching.] [Illustration: CHANNEL CEMENTING MACHINE. Coats surface of channel so it may be laid to cover stitches.] The surplus portion of the leather is now trimmed off on the Heel-Seat Rounding Machine, and the channel cut by the knife on the Rough Rounding Machine is turned up so that it leaves the channel open. This is done by the Goodyear Universal Channel Opening Machine, in which a little wheel, turning very rapidly, lays the lip smoothly back. ~SEWING THE SOLE TO THE SHOE~ The outsole is now sewed to the welt. This operation is performed on the Goodyear Outsole Rapid Lockstitch Machine, which is very similar in operation to the Goodyear Welt Sewing Machine used in sewing the welt to the shoe. The stitch, however, is finer and extends from the channel which was cut for it to the upper side of the welt, where it shows after the shoe has been finished. The lockstitch formed by this machine is a most durable one. Using a thoroughly waxed thread, it holds the outsole securely in place, even after the connecting stitches have been worn off. This is one of the most important machines in the shoemaking process. It is able to sew even in the narrow shank, where a machine using a straight needle could not possibly place its stitch. The “Star Channel Cementing Machine--Model A” is again called into operation for the purpose of coating with cement the inside of the channel in which this stitch has been made. A special brush with guard is used for this purpose, and the operation is very quickly performed by the skilled operator. After this cement has been allowed to set a sufficient length of time, the channel lip, which has previously been laid back against the sole, is again forced into its former position and held securely in place by rubber cement. This work is done by the Goodyear Channel Laying Machine, in which a rapidly revolving wheel provided with a peculiar arrangement of flanges forces back into place, securely hiding the stitches from observation on this portion of the shoe. [Illustration: MACHINES WHICH PUNCH THE SOLES OF SHOES CHANNEL LAYING MACHINE. Rubs channel lip down to cover stitches.] [Illustration: LOOSE NAILING MACHINE Drives small nails which hold outsole in place at heel.] The next operation is that of leveling, which is performed on the Automatic Sole Levelling Machine--one of the most interesting used in the shoemaking process. This is a double machine provided with two spindles, on one of which the operator places a shoe to be levelled. It is securely held by the spindle and a toe rest, and on the operator’s pressing a foot lever, the shoe passes automatically beneath a vibrating roll under heavy pressure. This roll moves forward with a vibrating motion over the sole of the shoe down into the shank, passes back again to the toe, then cants to the right, and repeats the operation on that side of the shoe, returning to the toe and canting to the left, repeating the operation on that side; after which the shoe automatically drops forward and is relieved from pressure. This rolling motion removes every possibility of there being any unevenness in the bottom of the shoe, and while one shoe is under pressure the operator is preparing a second one for the operation. [Illustration: AUTOMATIC LEVELLING MACHINE. Rolls out any unevenness in soles.] [Illustration: HOW THE HEEL OF A SHOE IS PUT ON TOP LIFT COMPRESSED HEEL BEFORE OPERATION AFTER OPERATION Heel Attaching WORK PERFORMED BY HEELING MACHINES.] [Illustration: AUTOMATIC HEEL LOADING AND ATTACHING MACHINE.] [Illustration: SLUGGING MACHINE. Drives small pieces of ornamental metal which protect the heel.] [Illustration: HEEL TRIMMING MACHINE. Trims rough lifts of heel to desired shape.] [Illustration: HEEL BREASTING MACHINE. Cuts the breast of the heel to correct angle and curve.] [Illustration: EDGE TRIMMING MACHINE. Trims edge of outsole smoothly.] [Illustration: A LUMP OF PULP. Paper such as found in this book is made from trunks and limbs of trees. The use of good fibers in book paper is a guarantee of quality and durability. The above illustration represents a lump of this pulp prepared for the beaters.] How the Paper in this Book is Made Where Does Paper Come From? Egyptians were the first people to make what would today be called paper. They made it from a plant called papyrus and that is where the name comes from. This plant is a species of reed. The Egyptians took stalks of reed cut into as thin slices as they could, laid them side by side; then they arranged another layer on top with the slices the other way and put this in a press. When dried and rubbed until smooth, it made a kind of paper, which could be written upon. One of the first substances used for making the kind of paper we have today was cotton. Paper was made from cotton about 1100 A. D. From this thin cotton paper our present papers are a development, i.e., paper today is largely made of vegetable fibers. Vegetable fibers consist mostly of cellulose surrounded by other things which hold the short vegetable fibers together. The fibers best adapted for making paper are those of the cotton and flax plants, and while the uses of paper were few, no other material was needed when it was once learned that cotton and linen fibers would do for making paper. All we had to do was to save all the old rags and sell them to the paper man. In making paper from rags, the rags were allowed to rot to remove the substances that incrust the cellulose, and then beaten into a pulp, to which a large quantity of water was added. This pulp was put into a sieve, until the greater part of the water had been drained off by shaking, and the fibers remaining formed a thin layer on the bottom of the sieve. This layer of fiber was put into a pile with other similar layers, and the whole pile was placed under a press, where more of the water was removed. When they were dry, we had a very fair kind of paper which was, however, not much better than blotting paper and could not be written on with ink because it was loose in texture and very absorbent. To give it good writing surface it was necessary to fill the pores. This was done by sizing which gave the paper great firmness. Paper was sized by drawing the layers of paper through a solution of alum and glue, or some similar substances, and then drying them, then finally passed between highly polished rollers to iron it. This gave it the necessary smooth hard surface. In the modern method of making rag paper by machinery, the rags are boiled with caustic soda, which separates the cellulose fibers, and placed in a machine in which rollers set with knives tear the rags to pieces and mix them with water to form a pulp. This is called a breaker. The pulp is then bleached with chloride of lime, and is passed on to the sizing machine. This machine mixes the pulp with alum and with a kind of soap, made from suitable resins which serves the purpose better than glue. [Illustration: NOT A WOOD YARD BUT THE OUTSIDE OF A PAPER MILL. This shows the great piles of trunks and limbs of trees near a wood pulp paper mill used in making paper for newspapers, books, magazines, etc.] How Is the Water Mark Put Into Paper? The pulp, which is now ready to be made into paper, is poured out upon an endless cloth made of fine brass wire. This cloth travels constantly in one direction, by means of rollers, and is given at the same time a sort of vibratory motion, to cause the paper fibers to become more closely felted together. On the wire cloth web are usually woven words, or designs, in wire, that rise above the rest of the surface. These are transferred to the paper, and are called water marks. The machine then winds the finished paper into rolls, so that it may be handled conveniently. ~HOW PAPER IS NOW MADE FROM WOOD~ During the past few years the uses for paper have increased so greatly that there have not been enough rags available to meet the demand for material, and a successful effort was made to find other material from which paper could be made. Many fibers were tried before it was found that wood pulp could be used. Straw and esparto grass, a plant that grows wild in North America, were found to yield cellulose having the desired qualities and were used to some extent. But the problem was solved when it was learned that pulp made from trunks and limbs of trees would serve even then. At first the powder formed by grinding up logs was used, but the paper produced was not strong, and could be used for very few purposes. [Illustration: GREAT FORESTS TURNED INTO PAPER PAPER TREES. This picture shows the trees as they grow in the woods. These trees are good for making paper. Your morning paper, may some morning be printed on what is left of one of these trees.] It was discovered finally that if wood shavings were boiled in strong solutions of caustic soda, in receptacles that would withstand very high pressure, the wood fibers were separated, and a very good quality of cellulose for paper manufacture produced, provided it was bleached before being made into paper, and most of our paper to-day is, therefore, made of wood. Later on this process gave way to the sulphite process. In the sulphite process, a solution of sulphite of lime is used. Acid sulphite of lime results when the fumes from burning sulphur are passed through chimneys filled with lime. By this process the separation of the fibers and the bleaching are done at the same time and an even whiter paper making material is obtained. The sulphite process is now used almost exclusively in making paper from wood. [Illustration: GRINDING ROOM. In this picture we see how the trees are first cut into smaller chunks before being reduced to chips for making pulp.] The discovery of the process of making paper from wood has led to the use of paper for many purposes for which it could otherwise never have been used. The wood pulp is also used in the form of papier-mâché, a tough, plastic substance, which is made by mixing glue with it, or by pressing together a number of layers of paper having glue between. Papier-mâché can easily be molded into almost any form, and after drying forms a very tough substance and one that will stand rough usage. It has been employed for making dishes, water baskets and utensils of many other kinds, for making the matrices for and from electrotype plates, for car wheels, and many other purposes. [Illustration: WHERE THE INGREDIENTS FOR MAKING PAPER ARE MIXED MIXING ROOM. The wood fiber must be mixed with other ingredients when paper is made from it. This shows a corner of the large electro-chemical department for the production of bleach and soda used in the preparation of rag and wood fibres.] [Illustration: THE WATER SUPPLY. A good deal of water is needed in making paper. From twelve to fifteen million gallons daily are drawn from the river and filtered through this plant in Maine; clean paper of bright color being dependent upon the use of pure water.] [Illustration: BEATING THE INGREDIENTS FOR MAKING PULP BEATER ROOM. The ingredients for making paper are first mixed thoroughly in machines called “beaters” before going to the paper making machines. The operation of beating is one of the most important in paper making.] [Illustration: THE PAPER COMING OFF IN ROLLS. As the paper progresses through the machines, it passes over a long series of heated cylinders, drying and hardening the stock until it reaches the finished end. This illustration shows a web 135 inches wide being cut into two rolls. The air pressure in the machine room is slightly greater than the atmospheric pressure outside, preventing dust from entering.] [Illustration: GREAT PAPER-MAKING MACHINES IN OPERATION PAPER MAKING MACHINES. In the foreground is the so-called wet end showing the vats in which the liquid pulp, about 98 per cent water, is pumped. It is screened and then flows on to an endless wire web beyond, where the free water is taken out by drainage and by suction boxes.] [Illustration: PUTTING THE PRINTING SURFACE ON THE PAPER PAPER STOCK. A large amount of stock of paper mills. This paper is seasoned by holding it in stock and will be later given such surface as is called for.] [Illustration: COATING MACHINES. Where the paper passes through a bath of coating mixture to a long drying gallery at the end of which it is rewound preparatory to being given the highly finished surface on the calendaring machine.] [Illustration: A section of Finishing Room department where paper is passed through alternating compressed fiber and steel rolls giving it the surface required for different classes of printing. The paper on which the Book of Wonders is printed has a highly finished smooth surface so that the pictures will come out clear.] [Illustration: WHERE THE PAPER IS CUT IN SHEETS The finished rolls of stock pass through rotary cutters which produce the sheets of various required sizes. The paper in the Book of Wonders was cut in sheets 41x55 inches, thus making it possible to print 32 pages on each side of each sheet.] [Illustration: Rotary Boiler for cooking rags or wood in making pulp for use in manufacture of paper.] Illustrations showing manufacture of paper by courtesy of S. D. Warren & Co. [Illustration: HOW THE PRINTED TYPE OF THIS BOOK WAS SET This picture shows the wonderful Linotype machine by which the type of this book was “set,” as the printers say. The men who operate the machine are compositors. Originally the type matter of books was set by hand and the compositor composed in type what the author of the book had written. By pressing down on the keys which you see in the picture, the compositor sets the words in lines of metal. This machine is almost human. By touching the proper keys, the operator assembles a line of matrices the details of which are explained in another picture, and after this is done the machine automatically casts a slug from them, turns and delivers a slug into a galley ready for use and finally distributes the matrices back into their respective channels in the magazine, where they are ready to be called down again, by the touch of the key button. The latest model linotype has four magazines and can be equipped with matrices which when assembled will cast lines in from six to twelve different sizes and styles of type. The assembling mechanism is the only part of the linotype where the human mind is applied to the working of the machine. It is necessary for the eye to read what is to be printed, and the mind, through the medium of the fingers, to translate this into assembled lines of matrices; after that the machine acts automatically.] [Illustration: THE LINOTYPE—FOUR MACHINES IN ONE The keyboard is made up of 90 keys, which act directly on the matrices in their channels in the magazine. The slightest touch on the keybuttons releases the matrix, which drops to the assembler belt and is carried swiftly to the assembler. When a word is assembled, the spaceband key is touched and a spaceband drops into the assembler. When the necessary matrices and spacebands to fill the line have been assembled, the operator raises the assembler by pressing a lever on the side of the keyboard. When the assembler reaches its highest point it automatically starts the machine and the matrices are transferred to the casting position. This illustration shows the manner in which matrices are constantly circulated in the Linotype. From the magazine they are carried to the assembler, then passed to the mold, where the line is cast, and from the mold after casting they are raised to the top of the machine and redistributed to their proper channels in the magazine. The Linotype is sometimes called a typesetting machine, but this is not correct: it does not set type. It is a substitute for typesetting. It is strictly speaking a composing machine, as it does composition but its product is not set type, but solid slugs in the form of lines of type with the printing face cast on the edge. It is in reality four machines so arranged that they work together in harmony--the magazine, the assembling mechanism, the casting mechanism and the distributing mechanism. The magazine is at the top of the machine sloping to the front at an angle of about 31 degrees, and consists of two brass plates placed together with a space of about five-eighths of an inch between. The two inner surfaces are cut with 92 grooves or channels running the up and down way of the magazine, for carrying the matrices. The matrices slide down these channels on edge, with the face or punched edge down, and the V-end extending toward the upper part of the magazine. Each of these channels will hold twenty matrices.] [Illustration: LITTLE PIECES OF BRASS WHICH PRODUCE SOLID TYPE ONE-LETTER AND TWO-LETTER MATRICES. Linotype matrices are made of brass. In the edge of each matrix is either one or two letters or characters in intaglio. The thickness of the individual matrices is dependent on the width of the character. By an ingenious arrangement either one-letter or two-letter matrices can be used in the same machine, and either character on a two-letter matrix can be used at will. The two-letter matrix bears two characters, one above the other, one of which may be a Roman face and the other an italic, small capital, or black face. If a line is to be composed partly of the Roman face, which is in the upper position on the matrix, and partly of the other face, which is in the lower position, this is accomplished by means of a slide on the assembler operated by a small lever. When the lower characters on the matrices are required, the slide is shifted and the matrices are arrested at a higher level, so that the lower characters align with the upper characters of the other matrices in the assembler. When the slide is withdrawn the matrices are assembled at the lower level. By means of this simple contrivance, a line may be composed partly of one face, partly of the other face, or entirely of either face.] [Illustration: THIS SHOWS HOW THE HEADINGS ARE MADE IN CAPITALS OF DIFFERENT TYPE. Linotypes are guaranteed to be capable of setting above 5000 ems of 6 point per hour, and this output is widely obtained in commercial printing offices with first class operators. When a compositor speaks of the amount of type he sets per hour or day he speaks of “ems.” A column of type matter is so many “ems” wide. The term “em” means the square of the particular size of type that is being set. Thus if a column is said to be 13 ems wide it means that an em quad or square, could be set 13 times in the width of the column. Type is graded according to size by points. Machine type for book work runs from 5 points to 12 points. A point is one seventy-second of an inch, that is, there are 72 points to an inch. This guarantee, however, by no means indicates the limit of speed at which the machine can be operated, as evidenced by records of 10,000 to 11,000 ems per hour maintained for an entire day. The rapidity of the Linotype is limited only by the ability of the operator to manipulate the keys, and the extreme capacity of the machine has never yet been attained.] [Illustration: HOW THE LINOTYPE MAKES SOLID TYPE SECTIONAL VIEW OF MAGAZINE SHOWING CHANNEL FULL OF MATRICES. This picture shows the machine with part of the magazine top and side removed. We can thus see how the matrices are arranged in their respective grooves in the magazine. When one of the keys of the keyboard is pressed down the first matrix in the corresponding grove in the magazine escapes and drops upon a conveyor belt and is carried in its proper order to an assembler, which answers much the same purpose as a printer’s stick. The correct spacing or justification of the line of matrices is accomplished by means of spacebands, which are assembled automatically between the words in the line by the touch of a lever at the left of the keyboard.] [Illustration: LINOTYPE SLUGS. Instead of producing single type characters, the Linotype machine casts metal bars, or slugs, of any length desired up to 36 ems, each complete in one piece and having on the upper edge, properly justified, the characters to print a line. These slugs are automatically assembled in proper order as they are delivered from the machine, when they are immediately available either for printing from direct or for making electrotype or stereotype plates. They answer the same purpose and are used in the same manner as composed type matter.] [Illustration: CASTING THE SLUGS OF SOLID METAL LINE OF MATRICES BEING LIFTED TO DISTRIBUTOR After the slug has been cast, the matrices are carried up to the second transfer position, where they are pushed to the right, and the teeth in the V at the top of the matrices engage the grooves in the distributor bar of the second elevator, which descends from the distributor box at the same time that the matrices rise to the second transfer position. The second elevator then rises toward the distributor box, taking the matrices with it, but leaving the spacebands; these are then pushed to the right and slide into the spaceband box, to be used again. As the second elevator rises toward the distributor box with its load of matrices, the distributor shifter lever moves to the left until the elevator head has reached its place by the distributor box. It then moves back to the right and pushes the matrices off the second elevator distributor bar into the distributor box, where they meet the “matrix lift” and are lifted, one at a time, to the distributor screws and distributor bar proper. The teeth in the matrix and the grooves in the bar are so arranged that when a matrix arrives at a point directly over the channel in which it belongs, it “lets go” and drops into its channel. If, however, there is a matrix in the line which was not designed to drop into one of the channels operated from the keyboard, it will be carried clear across the distributor bar and dropped into the last channel, and from there it will find its way to the sorts box.] [Illustration: SECTIONAL VIEW OF METAL POT WITH LINE OF MATRICES IN POSITION BEFORE THE MOLD The casting mechanism consists of the metal pot, mold disk, mold, ejector, and trimming knives. The illustration shows a cross-section of the metal pot, mold disk, and mold, with a line of matrices in the casting position. When the line of matrices leaves the assembler, they pass to a position in front of the mold disk. The disk makes a one-quarter turn to the left, which brings the mold from the ejecting position, where it stands while the machine is at rest, to the casting position. It then advances until the face of the mold comes in contact with the matrices. The metal pot advances until the pot mouthpiece comes in contact with the back of the mold; at this point the pump plunger descends and forces the metal into the mold and against the matrices. The pot then recedes, the mold disk withdraws from the matrices and makes three-fourths of a revolution to the left, stopping in the ejecting position, from which it started. The slug is ejected and assembled in the galley. During the last revolution of the disk the bottom of the slug is trimmed off, and in the process of ejection the sides of the slug are trimmed, so that when it drops in the galley the slug is a perfect line of type, ready for the form.] [Illustration: HOW THE PRINTED PART OF A BOOK LOOKS AT FIRST As the slugs of type, each of which represents a line, come from the linotype machine, they are arranged in order in a brass holder the width of the line of type, called a “galley.” This holder is about twenty inches long. As soon as it is filled one of the men in the typesetting office takes it to a proof press where he makes a rough impression of it. He runs an ink covered roller over the top of the slugs, lays a piece of blank paper on it and then either runs another roller over it or puts it in a hand press and secures an impression of the type just as it is. This is called making a “galley proof.” The galley proof is then sent to the proof-reader who reads it carefully and indicates such errors in setting as appear and must be changed. Before correcting the actual type, however, the composing room sends the galley proof to the one who is publishing the book. The publisher also reads the proof over carefully and, if he does not wish to change any of the wording, he sends it back to the composing room with his “O. K.” attached in writing. If he wishes to change the wording, he does so and the galley proof is then returned to the composing room marked “O. K. after corrections and changes are made.” The linotype operator then makes whatever changes are desired or necessary by setting new lines where mistakes or changes occur. If there is only one wrong letter in a line, he must reset the whole line as the machine, as you remember, only turns out solid lines of type. A revised proof is then sent to the publishing office and, if no further changes are to be made, he gives instructions to have the “galley” made up into pages. How the pages are made up is shown in the next picture.] [Illustration: HOW THE PAGES OF A BOOK ARE MADE UP When the revised proofs come back from the publisher ready to be made into pages, the publisher has marked on same what pictures are to go on the pages of the “make up” as this is called. The compositor then picks out the pictures in the form of cuts which are to go on the different pages and puts them in the page first. He then arranges the type matter from the galley proof around, above or below the pictures, puts in the proper headings and takes a “final proof” of how the pages are arranged to look. If this is satisfactory the publisher puts a “final O. K.” on the proof in writing and the page is ready to be printed. Thus the book is made up page by page. No page is printed without the O. K. of the publisher and so, if there are any errors still in the page, the publisher is responsible.] [Illustration: HOW THIS BOOK IS PRINTED PRINTING THE BOOK OF WONDERS This picture shows the pages of the Book of Wonders being printed. Thirty-two pages are printed on each side of a sheet of paper at one time. A printing office is a busy place as can be seen from the picture. As soon as the ink is dry on the printed sheets they are taken to the bindery where they are folded and sewed ready to have the covers put on.] [Illustration: HOW THE BOOK OF WONDERS IS BOUND When the printed sheets are received in the bindery they are fed into a folding machine which is shown here. A sheet of 64 pages is folded and cut and delivered in four sections of 16 pages each ready to be gathered.] [Illustration: Here we see a machine which takes the folded sections of 16 pages each, which are called “signatures,” and sorts them, dropping them into compartments in order, so that each compartment finally contains the printed matter for one book all arranged in the order which it will be bound.] Courtesy of the J. F. Tapley Co. New York. [Illustration: SEWING THE PAGES OF THE BOOK OF WONDERS Here we see the girls at work operating the sewing machines which sew the sections together at the back side of the book.] [Illustration: The men in this picture are making the backs of the books round and preparing them for the putting on of covers.] Courtesy of the J. F. Tapley Co., New York. [Illustration: THE BOOK OF WONDERS IS READY TO READ In this picture we see the “case makers” at work making the covers on which the actual book is bound.] [Illustration: The book is now “bound” by having the covers put on and is ready for distribution.] Courtesy of the J. F. Tapley Co., New York. How Is Photo Engraving Done? [Illustration: This cut shows a section of a photo-engraving screen enlarged, illustrating the squares above-mentioned. In reality it would take from 100 to 400 of these dots to make an inch, according to the fineness of screen.] ~HOW THE PICTURES IN THIS BOOK ARE MADE~ The first step is the making of the halftone negative which differs from an ordinary negative in being made up of different sized dots instead of shades of gray. This result is obtained by photographing the picture through a halftone screen consisting of two pieces of glass, ruled with black lines and cemented together so the lines cross at right angles and leave small squares of clear glass. The effect of making the negative in this way is to represent the different shades from black to white by large or small dots. Wet plate photography is usually used in this process because the film is thinner and more intensely black besides being cheaper than dry plates. [Illustration: New Process Engraving Co. This cut shows a portion of a halftone cut enlarged so that the dots can be seen very plainly.] Having made the negative the next step is to make a printing plate from it. To do this, a piece of metal, copper if the work is fine, and zinc for coarser work, is coated with a solution which is sensative to light, fish glue is commonly used to which is added a small amount of ammonium bichromate. The metal being coated and dried, it is put in a very strong frame with the negative and squeezed together so that they are in perfect contact. A powerful light is now directed upon the negative with the metal behind it, the result being that wherever the light goes through the white spaces in the negative, the coating on the metal is rendered insoluble. Where the dots on the negative are, the light is unable to get at the coating so that when the metal is removed from the frame and thoroughly washed this part of the coating washes away, leaving the part which the light got at attached to the metal. This is now heated until the enamel, as the coating is called, turns dark brown and the picture can be easily seen. The picture is now on the metal but it must be made to stand out in relief before it can be used for printing from, so it is put in a bath of acid which eats away that part of the metal left uncovered by the washing away of the coating and this leaves the dots which make up the picture standing up in relief. A roller covered with very thick paste-like ink is now rolled over the picture, or cut as it is now called, and when a piece of paper is pressed against the ink covered cut each little dot leaves a mark of ink on the paper the total making up the picture as we see it. There are many more wonderful things connected with the making of cuts such as the routing machine which has a tool that revolves so fast that it turns around 300 times while the clock ticks once, and other machines which cut hard metal as easily as you can cut a potato with a knife. Colored pictures are also made by the process outlined above. The picture is photographed three times with a different colored piece of glass in front of the lens, the result being three negatives, one of which has all the blue, one all the red and the other all the yellow in the picture. By making cuts from each negative and printing them on top of one another in yellow, red, and blue, the original picture is reproduced in all its colors. This is how all our pretty magazine covers are made. ACKNOWLEDGMENT The Editors of the Book of Wonders make acknowledgment herewith to the following. All mentioned have been a great assistance in making the book not only possible but authentic: Spencerian Pen Co. Eastman Kodak Co. American Telephone & Telegraph Co. Remington Arms Co. Bethlehem Steel Co. American Portland Cement Manufacturers Assn. Brainerd & Armstrong Silk Co. Corticelli Silk Co. Curtiss Aeroplane Co. U. S. Beet Sugar Industry. Hartford Carpet Co. Haynes Automobile Co. Jacobs & Davis, Engineers. Pennsylvania Railroad Co. Endicott, Johnson & Co. United Shoe Machinery Co. Sherwin-Williams Co. Pittsburgh Plate Glass Co. The Colliery Engineer. Lake Torpedo Boat Co. Western Union Telegraph Co. New York Edison Co. Westinghouse Lamp Co. Consolidated Gas, Electric Light and Power Co. of Baltimore. Browning Engineering Co. The White Star Line. Marconi Wireless Co. Plymouth Cordage Co. American Woolen Co. The Vitagraph Co. The B. F. Goodrich Co. The Goodyear Rubber and Tire Co. The Lexington Chocolate Co. The Hecker-Jones Milling Co. The White Oak Mills. The H. C. White Company. A. I. Root Company. Kohler & Campbell. Browne & Howell Co. P. & F. Corbin. Otis Elevator Co. Scientific American. Joseph Dixon Crucible Co. Homer W. Laughlin Co. S. D. Warren & Co. C. B. Cottrell & Sons Co. Mergenthaler Linotype Co. J. F. Tapley & Co. New Process Engraving Co. Mutual Film Corporation. Tobacco Trade Journal Co. McClure’s Magazine. James Arthur. Seth Thomas. American Locomotive Co. New York Central Railroad Co. Columbia Rope Co. Carl Werner. National Wool Growers Assn. INDEX =Acid=, carbonic, what it is, 509 =Aerial=, on ship, (illus.), 455 =Aeroplanes=, English Channel crossing (illus.), 132 Curtiss biplane (illus.), 131 first demonstrations of, 130 first flight in Europe, 129 first man-carrying (illus.), 128 first successful (illus.), 126 gas motors used in, 130 gliding, 137 greatest present value of, 136 records of, 131 red wing (illus.), 131 what two brothers accomplished for, 130 Wright Bros.’ inventions, 130 =Age=, why do we, 196 =Air=, does it move with the earth? 400 does it weigh anything? 398 dust in, 38 extend, how far does, 243 =Airlocks=, description of in tunnel building, 213 =Ammunition=, first invention of, 40 fixed, 47 in prehistoric times, 40 =Animals=, can they think? 194 is man an, 180 that leap greatest distance, 122 which foretell weather, 240 =Anthracite seams= (illus.), 260 =Aqueduct= (illus.), 505 =Are= matches poisonous, 294 =Armor=, in the Middle Ages, 44 =Army=, wireless in the, 448-451 =Are= there two sides to the rainbow? 254 =Arrow=, what causes it to fly? 408 =At= what point does water boil? 220 =At= what rate does thought travel? 242 =Australian Ballot=, where first used, 122 =Automobile= (illus.), axle, location of, 186 beginning of, 183 carburetor, location of, 184 carburetor, use of, 184 chassis, complete, 188 cog-wheels, use of, 183 cog-wheels, location of (illus.), 183 crankcase, location of (illus.), 183 cylinder, location of (illus.), 184 drive shaft, location of (illus.), 187 electric generator, use of, 185 exhaust, 184 fenders, location of, 188 fenders, use of, 188 finished car (illus.), 189 first American (illus.), 189 fly-wheel, location of (illus.), 183 fly-wheel, use of, 183 frame (illus.), 186 gasoline, what it does, 183 gasoline tank, location of, 187 gears, location of (illus.), 183 gears, use of, 183 heart of (illus.), 184 how improved, 190 magneto, location of, 185 magneto, use of, 185 marvellous growth of twenty years, 189 modern power plant complete, 190 oil pan, use of, 184 oil pump, location of, 184 piston, location of (illus.), 183 piston, use of, 183 power plant, an (illus.), 185 radiator, location of (illus.), 188 radiator, use of, 188 ready for the wheels, 187 second stage of construction (illus.), 186 self-starter, location of, 185 self starter, use of, 185 Smithsonian exhibit of complete power plant, 190 springs, location of (illus.), 186 springs, use of, 186 steering gear, location of (illus.), 187 street scene 20 years ago, 189 transmission, location of, 186 tire pump, use of, 185 tires, how made, 382 transmission, use of, 186 water pump, location of, 185 water pump, use of, 185 what the completed chassis looks like (illus.), 188 =Bacon, Roger=, discoverer of gunpowder, 44 =Balance=, effect of sunlight on, 37 =Baldness=, chief course of, 143 why some people are, 143 =Ball=, why it bounces, 63 bearings, what they are, 180 =Balloon=, what keeps it up, 199 why it goes up, 199 =Ballot=, when first used, 122 Australian, where first used, 122 =Bearings, Ball=, what they are, 180 =Bee=, how it lives, 336 why it has a sting, 336 =Bell, Alexander Graham= (illus.), 70 first telephone, 72 =Bend=, why things, 62 =Biplanes=, Curtiss (illus.), 131 in flight, Curtiss (illus.), 136 =Birds=, how do they find the old home? 408 how they learn to fly, 178 how they find their way, 407 reproduction of life in, 179 why do they sing? 408 =Birds’ Eggs=, why different colors, 233 =Blasting= gelatin, definition of, 206 =Bleriot, M.=, first European flights, 129 =Blotter=, capillary attraction of, 18 how it takes up ink, 18 =Blush=, why do we, 194 =Boat=, how it can sail under water, 269 hydroplane of submarine, 270 inside of a submarine (illus.), 272 =Bodies=, swiftest moving, 25 =Boiling= point of water, 220 what makes water, 220 =Boring mill= (illus.), 56 =Bottles=, gurgle in, 63 =Bounce=, why a ball will, 63 =Bow=, long (illus.), 42 =Bow-and-Arrow=, invention of, 43 =Boxes=, match, how made, 294 =Brazil, Emperor of=, receives first words over telephone, 74 =Bread=, how flour is made, 462 difference in Graham and whole wheat, 461 grinding wheat (illus.), 464 harvesting wheat, 460 loaves of world (illus.), 459 origin and meaning of, 460 purifying machine (illus.), 463 separating fibre germs (illus.), 463 wheat conditioning (illus.), 462 when wheat was first used in making, 461 where it comes from, 460 why so important, 460 =Break=, why things, 62 =Breech=, of a big gun, 53 =Breech-loaders= in Civil War, 48 in rifle, 47 =Brush=, in writing, invention of, 13 in writing (illus.), 13 =Bullets=, cupro-nickel used in, 50 grading of, 51 weighing of (illus.), 49 =Buildings=, concrete, how made (illus.), 100 =Buttons=, on sleeves, 64 =Building=, tallest in the world (illus.), 395-508 what holds it up? 496 =Building foundations=, construction of, 496 compressed air, use of (illus.), 500 cutting piles with a hot flame (illus.), 498 driving steel piles, 496 piles filled with concrete (illus.), 499 piles, length of, 497 piles, sinking of (illus.), 497 use of oxyacetylene, 498 =Cable, laying= armoring machine (illus.), 437 arrived on other side, 433 bulge (illus.), 437 gear-paying-out (illus.), 431 Great Eastern, the, 434, 437 landing of (illus.), 433 machinery on cable ship (illus.), 431 paying-out machine (illus.), 431 shore end of (illus.), 429 storing of, aboard ship (illus.), 430 what they look like when cut in two (illus.), 428 =Cable, ocean=, Continental Morse Code, 438 how dropped (illus.), 432 how repaired (illus.), 435 inventor of, 434 laid, how, 429 man who made it possible, 434 pioneers of, 434 signals as received (illus.), 438 what is it made of, 429 =Cable, repairing=, grapnels (illus.), 435 how repaired, 435 on rocky shore, (illus.), 438 powerful engines used (illus.), 436 splicing of (illus.), 436 =Cable, service=, map of Trans-Atlantic, 439 =Cable, vault=, of telephone (illus.), 67 =Cabriolet=, 122 =Cacao, beans=, bags of (illus.), 388 how cured, 392 nibs, 392 =Cacao=, flaked, how made, 392 how gathered, 391 pods, how gathered, 391 free, discovery of, 388 and chocolate, difference between, 389 =Cackling=, why a hen, 233 =Calibre= of a gun, 53 =Calico=, name, where from, 123 =Camera=, 22 first moving picture, 375 =Can= a bee sting? 536 =Can= animals think? 194 =Candles=, did they come before lamps? 294 why it burns, 21 why it gives light, 21 why you can blow out, 21-36 when introduced, 296 =Candy=, why do children like? 409 why does eating candy make some people fat? 409 =Carbon=, 352 =Carbonate of Soda=, used in developing, 23 =Carburetor=, in gas engine, 184 =Carpets=, carding machine (illus.), 170 dyeing the yarn, (illus.), 170 examining and repairing (illus.), 173 how yarn is dyed, 170 manufacture of (illus.), 169 modern, how made, 169 packing for shipment (illus.), 173 processes, 169-170-171, 173 stamping designs, 173 view of factory (illus.), 172 weaving, by machine (illus.), 171 wool, packing machine (illus.), 169 wool sorting, 170 =Cartridges=, invention of, 48 types of (illus.), 49 =Cave=, man who invented ammunition, 40 =Cement=, alumina in, 95 amount used in United States, 95 arch, 95 bagging (illus.), 99 bridges, 95 bucket (illus.), 97 burned (illus.), 98 calcined (illus.), 98 clay in, 95 crusher (illus.), 97 dams, 95 fireproof, 95 grinders (illus.), 98 industry, 95 in water, 95 kiln (illus.), 98 lime in, 95 machine (illus.), 97 marl in, 95 mill (illus.), 96-98 mixing (illus.), 99 mortar, 99 on farms, 95 origin, 95 plastic, 95 Portland, 95 powder (illus.), 98 quarry (illus.), 96 reinforced, 95 rock (illus.), 95-97 sewers, 95 shale in, 95 shovel (illus.), 96 sidewalks, 95 silica in, 95 strength of, 95 subways, 95 tunnels, 95 walls, 95 what is it, 95 what made of, 95 what used for, 95 weighing (illus.), 99 where obtained (illus.), 97 =Chalk=, where it comes from, 18 =Chattering=, why do my teeth, 218 =China-making=, blungers, 404 clay, in making dishes, 405 decorating cups (illus.), 404-406 dishes, how shaped, 405 glazing plates (illus.), 404 grinders (illus.), 404 how the dishes are shaped, 405 molding (illus.), 405 pressing water from clay (illus.), 405 pulverizing materials, 404 pulverizing mill (illus.), 404 saggers (illus.), 406 taking the dishes from kiln (illus.), 406 =Chinese=, probable discovers of gun powder, 44 =Chocolate=, broma, what it is, 390 cacao beans (illus.), 388 cacao pods, (illus.), 391 cacao tree, discovery of, 388 cocoa butter, 390 cocoa mill (illus.), 390 cocoa roaster (illus.), 390 cocoa shells, 390 cracking mill, 389 cream mixing (illus.), 393 difference between and cacao, 394 dipping department, 394 finisher (illus.), 392 flaked cocoa, 392 heating machine (illus.), 393 how are chocolate candies made? 394 how made, 392 making, 393 milk, how made, 394 mill (illus.), 392 mixer (illus.), 393 shell separator (illus.), 389 what cocoa butter is, 390 wrapping individual, 394 =Cigars=, how they are made, 517 =Clay=, what is, 495 =Circles=, tendency to walk in, 91 =Clinking= glasses, how it originated? 232 =Clock=, age of, 319 largest in the world (illus.), 321 machinery which runs a big (illus.), 322 in Independence Hall (illus.), 323 in New York City Hall, 323 =Cloth=, beaming (illus.), 89 Burling (illus.), 88 Burr picker, 87 chloride of aluminum in making, 98 English cap spinning (illus.), 89 finished, ready for market (illus.), 90 finish perching (illus.), 90 fulling (illus.), 90 how made from wool, 85 how made perfect, 83 how woolen is dyed, 87 mending perching (illus.), 88 napping, 89 piece dyeing (illus.), 90 ring twisting (illus.), 89 sulphuric acid solution in making, 87 teasel, 89 weaving and scouring (illus.), 88 web, 86 woolen mule spinning (illus.), 89 worsted carding (illus.), 85 yarn inspecting (illus.), 89 =Clothes=, cost of wool in a suit of, 83 of wool, 80 wool in one suit of, 83 =Coal=, anthracite, 257, 258 anthracite seams (illus.), 260 breaker (illus.), 257 cars ready to go to surface (illus.), 260 dangers to the miners, 262 electric cap lamp (illus.), 264 firedamp, 262 gas illuminating from, 299 gases, 262 history of the safety lamp (illus.), 263 how the miners loosen the coal (illus.), 261 how the slate pickers work (illus.), 259 lamp which saves many lives, 263 man who invented the safety lamp, 264 mine workers that never see day light, 258 mules and their drivers (illus.), 258 peat, 262 safety lamp and firedamp, 262 seams (illus.), 260 shaft gate (illus.), 260 slate pickers (illus.), 259 soft, 259 spiral slate pickers (illus.), 259 stable underground (illus.), 258 undercutting with compressed air machines (illus.), 261 undercutting with pick (illus.), 261 =Cocoa=, see Cacao =Cocoon=, description of, 115 completed (illus.), 116 from which moths have emerged (illus.), 117 how silk is reeled from, 118 moths emerging from (illus.), 117 number required to one pound of silk, 117 silkworm beginning of (illus.), 116 silkworm, preparing for making of (illus.), 116 =Coins=, gold, 266 in glass of water, 38 silver, 266 =Cohesion=, definition of, 219, 220 =Cold=, why some things are, 144 =Color=, exposed to light rays, 36 in paint, 229 what it is, 123 =Colors=, different in birds’ eggs, 233 in sunset, cause of, 253 =Color=, of rainbow, 253 red, why it makes a bull angry, 490 =Columbus=, brought first sheep to America, 80 =Comb honey=, development of (illus.), 529 =Compounds=, compared with elements, 349 =Compressed air=, method in building tunnels, 211 =Concrete=, buildings (illus.), 100 construction (illus.), 100 decay, 101 engineering, 102 forms (illus.), 100 houses (illus.), 101 loads (illus.), 100 mold, 101 ornamental (illus.), 100 practical uses of (illus.), 100 rusting, 100 Silo (illus.), 102 stable (illus.), 102 sun dial (illus.), 101 tensile strain, 104 tower (illus.), 102 walls (illus.), 100 water tower (illus.), 102 what it is, 95 wood, 102 =Confucius=, philosophy written with brush, 13 =Cooking=, when first used, 308 =Copper=, as a conductor of electricity, 267 wire, telegraph, 266 =Corn plant=, how pollen fertilizes, 170 why it has silk, 176 =Corn Silk=, what it is for, 176 baling presses (illus.), 476 =Cotton=, drawing frames (illus.), 472 slashers (illus.), 475 spinning frames (illus.), 473 warping machine (illus.), 474 what nation produces the most, 477 how much cloth will a pound of cotton make, 477 mill (illus.), 471 cloth, first steps in making, 472 putting fiber on bobbins (illus.), 473 cloth finished (illus.), 476 who discovered, 477 weave room, 475 where it comes from, 470 lapper machines, 471 card room (illus.), 472 bobbins (illus.), 473 dye-house (illus.), 474 beaming frames (illus.), 475 inspecting tables (illus.), 476 field a southern (illus.), 470 breaker machines (illus.), 471 slubber machines (illus.), 472 speeders (illus.), 473 spooling machine (illus.), 474 shipping (illus.), 476 what used for, 477 cloths, what are the principle, 477 =Counting=, man, himself, 19 in tens, 19 in twelves, 20 =Crying=, what makes us, 195 when hurt, why we, 93 =Cross-bow=, invention of, 44 =Crude rubber=, how treated, 378 =Culverins=, early type of, 45 =Cylinder in gas engine= (illus.), 184 =Darkness=, cats can see in, 91 some animals can see in, 91 why we cannot see in, 91 why we fear, 352 =Deep sea diving=, the telephone adjusting (illus.), 202 coming up (illus.), 204 cost of outfit, 203 helmet, putting on (illus.), 202 just before going down (illus.), 204 outfit, 202 shoes, putting on (illus.), 202 suit, putting on (illus.), 202 telephoning from bottom, 203 telephone, testing the (illus.), 203 testing, final (illus.), 203 water pressure at varying depths, 203 wealth recovered by diving, 204 weight of outfit, 203 =Deer-stalking with the cross-bow= (illus.), 42 =Detonators=, in firearms, 47 =Developer=, Pyro, in photography, 23 =Diamonds=, what made of, 351 =Did= candles come before lamps? 294 =Die=, why do we have to, 245 =Difference= in woolens and worsteds, 84 =Dimples=, what causes, 352 =Discovery= of gunpowder, 44 =Discovery= of stringed musical instruments, 479 telephone, 71 =Diver’s= task made easy (illus.), 284 =Diving, deep-sea=, the telephone adjusting, (illus.), 202 cost of outfit, 203 hats of divers, 204 just before going down (illus.), 204 helmet, putting on (illus.), 202 shoes, putting on (illus.), 202 suit, putting on the (illus.), 202 suit, what consists of, 202 telephone from bottom, 203 telephoning, testing the (illus.), 203 testing final (illus.), 203 water pressure at varying depths, 203 wealth recovered by diving, 204 weight of outfit, 203 =Dixie=, what name means, 124 where name originated, 123 =Does= air weigh anything, 398 =Does= the air surrounding the earth move with it? 400 =Does= thunder sour milk, 196 =Does= light weigh anything? 37 =Does= the sun revolve on its axis? 511 =Do= father and mother plants always live together? 176 =Do= the ends of the rainbow rest on land? 254 =Do= the stars really shoot down? 255 =Dog=, why he turns round before lying down, 229 =Dolls=, why girls like, 368 =Dom Pedro=, Emperor of Brazil, who saved the telephone, 73 =Do= plants breathe? 241 =Draft=, created by chimney, 37 =Dreams=, cause of, 366 nightmare, 367 what makes us? 366 =Drinking=, origin of clinking glasses, 232 =Driving shield=, airlock bulkhead (illus.), 210 erector (illus.), 210 in tunnel building (illus.), 208 inventor of, 209 tunnels, front view (illus.), 209 =Ducks=, why water runs off backs of, 233 =Dust=, in air, 38 what it is, 104 =Dyeing=, silk, 121 =Earache=, what causes, 410 =Earth=, how big it is, 124 light surrounding, 38 =Echo=, what makes an, 200 whispering gallery, 201 =Eggs=, birds why different colors, 233 silkworm, how imported, 111 =Egyptians=, how ancients wrote, 12 =Electric arc=, temperature of, 35 =Electric current=, what it is, 334 =Electricity=, conductors of, 331 current, 334 good conductors, 331 how discovered, 333 non-conductors, 331 what is, 329 =Electric lighting=, arc-light, 307 Edison’s first lamp (illus.), 306 incandescent carbon lamp (illus.), 306 Mazda lamp (illus.), 306 tantalum lamp (illus.), 306 Tungsten metal lamps, 305 when introduced, 305 =Elements=, carbon, 352 compared with compounds, 349 hydrogen, 349 nitrogen, 350 oxygen, 349 what an is, 349 =Elevator=, description of (illus.), 397 installation (illus.), 396 principal parts of, 396 why does not the car fall? 397 =Emperor=, saved the telephone, 73 =Emperor of Brazil=, receives first message over first telephone, 74 =Engine, gas= (illus.), 181-182 carburetor, 184 cylinder (illus.), 184 horse-power, of, 256 =Exchange=, first telephone, 75 =Exhibition=, of first telephone at Centennial, 74 =Experiments=, with mirror resultant in photograph, 22 =Exploding=, a submarine mine, 34 =Explosions=, how they break windows, 62 in gas engines (illus.), 182 of submarine mines (illus.), 34 what happens in, 205 =Explosives=, definition of, 205 blasting gelatin, 206 gun-cotton, 206 nitroglycerine, 206 =Eye=, of a submarine (illus.), 274 =Eyes=, closed, walking with, 91 hand quicker than, 376 help brain in walking, 91 in some pictures follow you, why, 36 keeping body balanced, 91 nature’s way of protecting, 38 protecting with tears, 38 sparkle when merry, why, 92 why we can’t sleep when open, 92 why we see stars when hit on, 268 =Eye-wash=, tears as an, 38 =Fabrics=, worsted, 85 =Fahrenheit=, what is meant by, 221 why so called, 221 =Fastest= camera in the world, 25 =Fathers and Mothers=, do plants have, 175 =Federal Government=, grazing fee paid to, 82 =Fertilization=, in birds, 179 how corn plant fertilizes, 176 of fishes, 177 =Fight=, of Merrimac and Monitor, 32 =Film=, before and after snapshot, 23 sensitive, 23 =Finger prints=, arch, (illus.), 520 composite (illus.), 521 of different people, 521 enlargements of, 524 how they identify us, 520 impressions of orang-outang (illus.), 522 loop (illus.), 520 palmary impressions (illus.), 522 specimen form of, record (illus.), 525 spike that caught a criminal (illus.), 524 thieves caught through their, 523 thumb imprint on bottle (illus.), 523 thumb impression on cash box (illus.), 523 thumb mark on a candle (illus.), 523 where first used, 522 whorl (illus.), 521 =Fingers=, why they hurt when cut, 143 why we have ten, 142 =Finger nails=, why we have, 142 =Fire=, alarms when first used, 308 first apparatus to fight, 308 first fire department, 308 first real, fire engine, 308 gases put out, 37 how man discovered, 289 how man learned to fight, 208 how man learned to make a, 289 mark, of civilization, 290 why it goes out, 37 why is it hot? 401 why put out by water, 222 =Fire making=, drilling (illus.), 289 drilling with bow string (illus.), 290 drilling, two persons (illus.), 290 first matches (illus.), 292 flint and pyrites (illus.), 290 flint, introduction of (illus.), 291 plowing (illus.), 290 pyrites (illus.), 290 rubbing sticks together, 42 sawing (illus.), 289 steel and flint (illus.), 291 tinder box (illus.), 291 tinder box, pistol (illus.), 291 with matches, 292 =Firedamp=, 262 explosion in safety lamp, 262 =Firearms=, first crude efforts of, 45 first real (illus.), 45 fuse of, 45 in early Chinese history, 44 first trigger of, 45 =Firing=, mortar, causes gas-rings, 27 =First= man-carrying aeroplane, 128 real telegraph, 421 stringed musical instrument, 480 telephone (illus.), 72 telephone line, 72 telephone switchboard (illus.), 74 =Fishes=, how they are born, 177 how they come to life, 177 motion in swimming, 233 what the eggs are, 177 why they cannot live in air, 232 =Flag=, made, how was American, 310 made, when was American? 310 =Flash pan=, early type, 45 =Flaxseed oil=, what it is, 227 =Flight=, of projectile, long, 30 =Flint-lock=, invented in seventeenth century, 46 invented by thieves, 46 still in use in Orient, 46 =Floor=, sounds through a, 79 =Flour=, bolters (illus.), 465 how made, 462 purifying machine (illus.), 463 sieves, 465 =Flowers=, why they have smells, 176 =Flying=, how birds learn, 178 boat, wonderful (illus.), 133 first Langley monoplane, 126 first successful aeroplane (illus.), 126 machine, first models, 127 some of the men who helped, 126 ten years of (illus.), 137 =Flying boat=, fun in (illus.), 135 gliding by, 137 =Flying boat=, interior arrangement (illus.), 134 monoplane type (illus.), 135 six-passenger hull (illus.), 134 speed of (illus.), 135 the wonderful, 133 views of (illus.), 133 =Flying machines=, 126 Bleriot flew in Europe (illus.), 129 Curtis biplane in flight (illus.), 136 Dr. Langley’s flying (illus.), 127 early types of, 127 first demonstrations, 130 first flight in Europe with, 129 first man-carrying aeroplane, 128 first models, 127 flying boat, 133 flying boat, exterior arrangement, 134 gliding experiments, 137 government interest in, 138 hull of flying boat, 134 interesting governments in, 138 Wright Bros., first flights, 130 =Focus=, in eye, 22 =Fog=, what it is, 105 =Food=, how we learned to cook, 308 =Foreign monoplanes=, some famous (illus.), 132 =Forsythe, LL.D. J.=, inventor of the primer, 47 =Freckles=, what makes them come, 125 =Fuse=, for firearms in early history, 45 =Funditor=, 42 =Gas=, acetylene, 305 definition, 348 first structure to be lighted by, 302 in coal mines, 262 water, 305 =Gas, illuminating=, Baltimore first city to use, 302 carbon in, 302 discovered, when, 302 first American house to use, 302 first practical demonstration of, 302 generator house (illus.), 299 holder (illus.), 298 how it gets into jet, 302 how it is purified, 303 how made, 303 how the meter works, 304 hydrogen in, 302 impurities removed from (illus.), 301 jet, the story in a, 303 made of, 302 meter, description, 304 purifying boxes (illus.), 301 removing tar from, 300 shaving scrubbers (illus.), 300 =Gasoline engine= (illus.), 181, 182 =Gases=, generated at gun muzzle, 27 how expelled in gun ingot, 55 hydrogen, 349 nitrogen, 350 oxygen, 349 tendency to put out fire, 37 =Gas-rings=, in firing motor, 27 =Gatling=, inventor of guns, 310 =Gelatine=, in photography, 23 =Gestures=, talking by, 18 =Ghosts=, what are they? 367 =Glad=, why do we laugh when, 92 =Glass=, why it cracks, 63 how long known, 247 =Glass, plate=, casting (illus.), 249 commercial, 246 plate and window glass compared (illus.), 252 =Glass, plate, making=, annealing, oven, 249 beveling, 247 blanketing, 252 clay mixing (illus.), 248 clay trampling (illus.), 248 clay used, 247 grinding table, 250 materials used in, 247 mercury, 253 nitrate of silver, 253 pots (illus.), 248 pots, drying of, 248 pots, length of usefulness, 248 silvering, 247 skimming the pot (illus.), 249 treading, 247 =Glow-worm=, why does it glow? 231 =Gold=, why is it called precious? 266 =Gong=, why does it stop when it has been sounded, 78 =Good luck=, why a horseshoe brings? 311 =Graphite= in lead pencils, 468 =Gravitation=, what is, 267 =Gravity=, center of, in gun, 61 =Gravity=, force of, 61 =Greek fire=, in early history, 44 =Growing=, why do we stop, 195 =Gun=, action at muzzle, 27 annealing a gun ingot, 57 assembling of, 48-54 arquebus of, 1537, 47 barrels, erosion of, 35 blow-holes, 56 bore searcher, 59 breech of a, 53 discharges, force of, 33 calibre of a, 53 elastic limit, 58 elongation, 58 forging a (illus.), 52 heat treatment, 58 hoops of a, 54 improvements in, 45 ingot, calibre of, 55 jacket of, 54 length of a, 53 liner of, 54 life of, 35 manufacture in America, 48 measuring inside diameter (illus.), 59 modern built-up (illus.), 54 mold for ingot, 55 muzzle of, 53 pressure generated in a big gun, 54 photography (illus.), 33 piping, 56 powder chamber of a, 53 rifling (illus.), 60 rifling of, 53 shrinking pit, 59 tensile strength of, 58 factory, testing materials, (illus.), 50 tube of, 54 tube, how it is tempered, 57 why called gatling, 310 wire-wound, 54 =Gun-barrels=, imported from England, 49 resisting pressure of, 34 =Gun-cotton=, in smokeless powder, 35, 206 =Gunpowder=, Chinese probable discovers of, 44 discoverer of, 44 experiments by Schwartz, 45 formula of Roger Bacon, 45 ingredients in, 205 manufactured in monasteries, 44 what causes the smoke? 206 smokeless, what made of, 206 why some is fine and others large grained, 206 =Gurgle=, in bottles, 63 =Hail=, what causes, 124 =Hair=, what causes baldness, 143 why it don’t hurt when cut, 143 why it keeps growing, 144 =Hand bombards=, early types, 45 =Hands=, shaking, why with the right, 231 =Hansom=, why so called, 122 =Have= plants fathers and mothers? 175 =Heart=, why beats during sleep, 191 why beats faster when scared, 191 why beats faster when running, 191 =Heat=, light wave changed into, 36 why a nail gets hot when hammered, 230 why some things are warm, 144 how we obtain, 231 =Hemp=, Manilla (illus.), 356 =Hobson’s choice=, how originated, 311 =Honey=, apiary in summer (illus.), 534 how produced, 527 worker comb (illus.), 532 manner of using German bee-brush, 533 finished product (illus.), 533 frame (illus.), 535 how to bump the bees off a comb (illus.), 533 bee-hat (illus.), 535 a study in cell-making (illus.), 532 bee sting, can a, 536 frame of bees (illus.), 535 comb, how bees build, 536 =Honey-bee=, poison-bag, 537 egg of queen, under microscope (illus.), 529 preparing for rearing, 531 living on combs in open air, (illus.), 527 the daily growth of larvæ (illus.), 532 effect of a sting (illus.), 536 worker-bee (illus.), 527 what the queen-bee does? 528 drone-comb (illus.), 532 clipping queen bees wings (illus.), 533 cucumber blossom with bee on it (illus.), 528 queen-bee (illus.), 527 the queen and her retinue (illus.), 529 queen-rearing, 531 queen-cells (illus.), 529 =Honeymoon=, why do they call it a? 311 =Horizon=, how far away is the, 245 what is it, 244 where is it, 244 =Horse-power=, a, what it is, 256 =Horseshoes=, why it is said to bring good luck? 311 =Hot box=, cause of, 368 =Houiller=, French gunsmith, 48 =Houses=, concrete (illus.), 101 =How= far does the air extend? 243 is ammunition made (illus.)? 49 does an arc light burn? 307 are automobile tires made? 382 does a honey bee live? 336 does a bee make honey? 527 do bees build the honey comb? 536 does the honey bee defend itself? 536 does honey develop in a comb (illus.)? 530 do birds learn to fly? 178 do birds find their way? 407 does the blotter take up the ink of a blot? 18 this book is bound, 578 this book is made, 561 the paper in this book is made, 561 the pictures in this book are made, 581 are bullets made? 51 is an ocean cable laid? 429 does a camera take a picture? 22 is a cable dropped into the ocean (illus.)? 432 are modern carpets made? 169 is a carpet woven by machinery? 171 is china decorated? 406 is china made? 404 is chocolate made? 392 did the custom of clinking glasses in drinking originate? 232 are cigars made? 517 is cloth made from wool? 86 did the coal get into the coal mines? 257 does a coal mine look inside? 260 do the cocoa beans grow (illus.)? 391 is the color put on the outside of the pencil? 469 is the honey comb made? 532 are concrete roads built (illus.)? 103 did man learn to cook his food? 308 are concrete buildings made (illus.)? 100 is woolen cloth dyed? 87 big is the earth? 124 much of the earth does the sun shine on at one time? 324 does an elevator go up and down (illus.)? 396 was electricity discovered? 333 does the light get into the electric bulb? 305 is the eraser put on a pencil? 469 can an explosion break windows? 62 explosions may occur on submarines, 278 does the farmer use concrete (illus.)? 102 do our finger prints identify us? 520 did man learn to fight fire? 308 did man learn to make a fire? 289 are fishes born? 177 was the flag made? 310 is flour made? 462 does a fly walk upside down? 454 did men learn to fly? 126 does the gas get into the gas jet? 302 is illuminating gas made? 303 is gas purified? 303 is plate glass made? 246 is plate glass ground? 250 a wire-wound gun is made? 54 was the first American gun made (illus.)? 47 is a gun ingot made? 55 do we find the length of a gun? 53 is a gun tube tempered? 57 do we obtain heat? 231 the heel of a shoe is put on (illus.), 560 did Hobson’s choice originate? 311 far away is the horizon? 245 does a key turn a lock (illus.)? 491 does a spring lock work (illus.)? 492 are lead pencils made? 467 do the miners loosen the coal? 261 is light produced, 230 are magnets made? 335 are matches made? 293 are match boxes made? 294 did man learn to send messages? 412 does the meter measure the gas? 304 can microbes spread through the body? 410 are mirrors silvered? 522 big is a molecule? 348 did money originate? 455 are moving pictures made? 369 does the music get into the piano? 478-482 did the word news originate? 312 did a nod come to mean yes? 19 did shaking the head come to mean no? 19 are paints mixed? 228 is a photograph developed? 23 was the piano discovered? 479 do plants breathe? 241 do plants reproduce life? 175 does the shield cut through the ground in tunnel building? 212 are shooting shells photographed? 24 shoes are made by machinery, 549 shoe machinery was developed, 457 is crude rubber secured? 377 is rope turned and twisted? 358 are rubber tires made? 378 are modern rugs made? 169 to splice a rope, 364 do men go down to the bottom of the sea? 202 did the sand get on the seashore? 108 far back does the silkworm date? 109 was silk introduced into Europe? 110 are the silkworms cared for? 113 do we know a thing is solid, liquid or gas? 348 are sounds produced? 485 fast does sound travel? 486 can sound come through a thick wall? 79 is the volume of sound measured? 242 far does space reach? 256 do the slate pickers work? 259 does a captain steer his ship across the ocean? 407 can a ship sail under water, 269 is a submarine submerged? 270 do sponges grow? 286 do sponges eat? 287 are sponges caught? 287 are the stars counted? 241 big is the sun? 141 hot is the sun? 141 is a steel pen made (illus.), 17 did man learn to shoot, 40 do we get wool off the sheep? 82 is a stone thrown with a sling? 41 are metallic and paper shells filled with powder? 50 did man learn to talk? 18 did the telephone come to be? 70 fast does thought travel? 242 does a telegram get there? 414 did man learn to tell time? 313 did man begin to measure time? 314 did men tell time when the sun cast no shadows? 317 is the time calculated at sea? 315 is tobacco cultivated? 516 is tobacco cured? 516 was tobacco discovered? 512 is tobacco harvested? 515 is tobacco planted? 514 is a tunnel dug under water? 208 does water put fire out? 222 is white lead made? 225 are wires put under ground? 76 did writing first come about? 11 did the Chinese write? 13 did the Monks do their writing? 14 does a pen write? 18 much does the wool in a suit of clothes cost? 83 much wool does America produce? 82 is wool taken from the sheep? 82 is the yarn for carpets dyed? 170 is oxide of zinc obtained? 226 does the water get into the faucet? 501 are the big water pipes laid? 504 did the name Uncle Sam originate? 458 =Human body=, wonders of the, 311 =Hunting=, with the bow-and-arrow, 43 =Hurt=, why we cry when, 93 =Hydrogen=, what it is, 349 =Hypo=, used in developing, 23 =Impact=, of projectile from guns, 28 =Ink=, how does a blotter take up? 18 =Instruments=, artillery, testing, 24 musical, 488 optical, based on refraction, 38 =Incandescent lamp=, development of, 306 =Inside= of a mine planting submarine (illus.), 277 =Iron=, cast, 265 melts at, 35 the most valuable metal, 265 wrought, 265 =Is= a moth attracted by a light? 288 man an animal? 180 the hand quicker than the eye? 376 there a reason for everything? 200 there a man in the moon? 400 yawning infectious? 192 =Jacket=, of a gun, 54 =Japan= the natural home of the silk worm (illus.), 112 =Kentucky rifles=, 45 =Key=, how it works in a lock (illus.), 491 =Knots=, different kinds of (illus.), 363 what makes, in boards, 223 =Lambs=, Siberian, in South Dakota (illus.), 80 =Lamps=, first street light in America, 296 the Clanny safety, 264 did candles come before? 294 earliest forms of, 295 Edison’s first (illus.), 306 incandescent carbon (illus.), 306 incandescent, development of, 306 incandescent, electric, when invented, 305 French watch tower (illus.), 295 Mazda (illus.), 306 from Nushagak hanging (illus.), 297 Pagan votive (illus.), 296 Tantalum (illus.), 306 street, when first used, 295 chimney protects flame, 37 coal miners and safety, 262 =Lamp chimney=, why it makes a better light, 37 =Langley, Dr. Samuel P.=, 1914 flight of aeroplane, 128 =Languages=, why so many, 197 =Lantern=, the first oil (illus.), 297 the “Réverbère” (illus.), 297 =Laugh=, when glad, why we, 92 nerves, 93 when tickled, why we, 93 =Laughter=, reflex action, 93 =Lead=, as used in making paint, 267 in a pencil, 468 why so heavy, 267 as used in pipes for plumbing, 267 =Leather=, how the hides are treated, 539 treatment of hides, 538 unhairing machine (illus.), 540 hide house (illus.), 538 tanning process, 539 rolling room (illus.), 539 tanning sole leather, 539 how upper leather is tanned (illus.), 540 disposing of waste material, 540 wringers, 539 tan yard (illus.), 539 =Legs=, not same length, 91 =Lens=, in the eye, 22 =Leyden jar=, what it is, 332 =Life=, beginning of, 174 beginning of man’s, 174 how plants reproduce, 175 =Light=, attracting moths, 288 glow-worms why they glow? 231 how produced, 230 lightning bugs, made by, 231 where it goes when it goes out, 36 what makes match, 198 in mirror, 22 in negative, 23 rays, 36, 495 broken rays of, 38 rays, heat from, 36 and refraction, 38 speed of, 36, 140 travels faster than anything in the world, 36 surrounding earth, 38 wave changed into heat, 36 =Lighting=, arc, how does it burn, 307 in America, first street (illus.), 296 first oil lantern, 297 electric, when introduced, 305 first street light in Paris, 297 gas tank, (illus.), 298 =Lightning=, why it follows thunder, 140 =Lightning bugs=, why they produce light, 231 =Lignite=, found in coal mines, 262 =Liner=, of a gun, 54 =Linseed oil=, extraction of, 228 what it is, 227 where it comes from, 227 =Liquid=, definition, 348 =Living=, why do some people live longer, 199 reproduction necessary why, 174 reproduction of, in birds, 179 reproduction of, in fishes, 177 =Loading= machines in powder factory, 50 =Lobsters=, red, what makes them, 245 =Lock=, cylinder (illus.), 492 how a key turns a (illus.), 491 how key changes are provided (illus.), 491 how a spring lock works (illus.), 492 master-keyed cylinder (illus.), 492 what happens when the key is turned? (illus.), 491 what happens when the knob is turned? (illus.), 491 =Locomotives=, boiler of articulate type (illus.), 440 boiler of (illus.), 442 cab of (illus.), 442 cylinders description of, 441 low pressure cylinders of (illus.), 441 electric, newest (illus.), 443 one of the largest (illus.), 440 signal tower, latest (illus.), 444 stoker, automatic (illus.), 443 water tank (illus.), 444 =Lodestone=, what it is, 327 “=Long Bow=,” in Sherwood Forest (illus.), 42 =Loom=, cloth making machine, 86 =Magnet=, breaking iron (illus.), 330 electro (illus.), 326, 328, 335 electric lift (illus.), 326 experiments with, 327 great lifting by (illus.), 330 how made, 335 what makes it lift things? 326 wonders performed by, 326 work it can do (illus.), 328 =Man=, writing, how man learned, 11 counting himself, 19 is he an animal? 180 =Matches=, are they poisonous? 294 first, 292 how made, 293 lucifer (illus.), 292 making by machinery, 293 modern safety (illus.), 292 oxymuriate (illus.), 292 promethean (illus.), 292 what we would do without, 292 when first used (illus.), 292 =Match-lock=, of early firearms, 45 =Melting= of iron, 35 =Men= who made the telephone, 70 =Mercury=, fulminate of, 49 =Merrimac and Monitor=, fight of, 32 =Merry=, why eyes sparkle when, 92 =Messages=, how men learned to send, 412 Indian smoke signals, 412 marathon runner by (illus.), 413 pony telegraph (illus.), 413 =Messenger boy=, how to call a (illus.), 414 the first (illus.), 413 =Metal=, what is a, 265 what is the most valuable? 265 why we use for coining, 456 =Meter=, description of gas, 304 how it measures gas, 304 =Milk=, does thunder sour? 196 =Milky way=, why is it called, 255 what is, 255 =Mine cars= (illus.), 260 =Mines=, clearing channel of buoyant, 283 exploding submarine, 34 planting submarine, inside of (illus.), 277 workers that never see daylight, 258 =Mirror=, collects rays of light, 22 reflection in, 22 reflects rays of light, 22 =Mirrors=, beveling (illus.), 251 how made, 251 how silvered, 252 polishing, 251 roughing, 251 silvered with mercury, 253 silvering mirror plates (illus.), 252 =Molecule=, how big is a, 348 what is a, 348 =Monasteries=, where gunpowder was manufactured, 44 =Money=, how originated, 455 metallic forms of, 456 who made the first cent, 458 who originated, 455 why do we need, 455 why gold and silver are best for coining, 457 =Monitor and Merrimac=, fight of, 32 =Monks=, making gunpowder, 44 =Monoplane=, flying boat (illus.), 135 German (illus.), 132 over Mediterranean (illus.), 132 =Moon=, why it travels with us, 399 the man in the, 400 =Morse, S. B.=, inventor of telegraph, 420 =Mortars= (illus.), 26 =Mothers and Fathers=, do plants have, 175 =Moths=, attracted by light, 288 emerging from cocoon (illus.), 117 =Motion= bodies, swiftest, 25 =Motion=, is train harder to stop than start? 223 of light, 140 of sound, 140 perpetual, 61 perpetual, in mechanics, 240 =Motors=, gas, used in aeroplanes, 130 =Mountains=, what made them, 401 =Moving pictures=, Board of Censors, 373 developing room (illus.), 372 drying room (illus.), 373 continuous movement of film, 376 exact size of film, 370 first camera, 375 first exhibited at studio, 372 how made, 369 how freak pictures are made, 376 negative, stock, 370 negative, perforated, 370 “Pigs is Pigs” (illus.), 374 rehearsing (illus.), 371 scenario (illus.), 374 staging, 371 taking a (illus.), 373 =Mulberry trees=, food for silk worms (illus.), 112 =Mules and drivers= (illus.), 258 =Multiple switchboard= of telephone, 69 =Music=, harp, 479 lyre, 479 note, what it is, 490 what pitch is, 489 what is, 478 =Musical talking machines=, 490 =Muzzle=, of a big gun, 53 =Muzzle-loaders=, in Civil War, 47 =Nails=, why they get hot when hammered, 230 =Names=, of people, 20 =Nature=, protecting eyes, ways of, 38 =Navigating= on bottom of sea, 283 =Negative= in photography, 23 =Nerves=, sensory, receive impression, 93 transmitting impression, 22 =News=, how did the word originate? 312 =Nightmare=, cause of, 367 =Nitrogen=, what it is, 350 =Ocean=, why is it blue? 219 what makes it green? 219 why don’t water sink in? 219 where did all the water in, come from? 218 where is water at low tide, 219 =Of= what use is my hair? 143 =Of= what use are pains and aches? 410 =Oil baths=, for gun (illus.), 57 =Oil cake=, from linseed, 228 =Oil=, palm olive, in soap, 411 =Omniscope=, of submarine boat, 271 =Onions=, make tears, 38 bad effect of on eyes, 38 =Operatives=, in powder factory, girls as, 49 =Optical instruments=, based on refraction, 38 =Organic matter=, what it is, 174 =Origin of cement=, 95 of counting in tens, 19 names of people, 20 of nodding to indicate yes, 19 of shaking head to indicate no, 19 of turnpike, 104 =Oxide of zinc smelter= (illus.), 227 how obtained, 226 =Oxygen=, what it is, 349 in air, 37 =Pain=, of what use is, 410 what it is, 244 =Paint=, care of, story in, 224 how mixed, 228 uses of, 224 what used for, 224 =Paint manufacturing=, colors, what makes different, 229 buckles before corrosion (illus.), 225 buckles after corrosion (illus.), 225 buckles placed in stacks (illus.), 225 buckles taken from stacks (illus.), 225 first step in making (illus.), 224 lead buckles making (illus.), 224 lead, white, how made, 224-225 lead white used in, 224 grinding lead in oil (illus.), 228 washing the lead (illus.), 226 mixing, 228 where paints are mixed (illus.), 228 linseed oil, where obtained, 227 pressing oil from flaxseed (illus.), 228 removing oil cake from press, 228 sulphur roasting furnace (illus.), 226 zinc smelter (illus.), 227 oxide of zinc, how made, 226 =Paper=, earliest forms of, 14 sensitive in photography, 23 shells, inspection of (illus), 49 papyrus, the first, 14 =Papyrus=, invention of, 14 =Patents=, of original telephone, 73 =Peat=, as a fuel, 262 =Pen=, first metallic (illus.), 15 first steel (illus.), 15 first metallic pen, how made, 15 how it writes, 18 invention of the, 15 =Pencils, “lead”= where from, 466 eraser is put on, 469 making description of (illus.), 467 who made the first? 466 =Periscope=, description of, 275 how we look through a (illus.), 276 mirror of, 275 =Perpetual motion=, nearest approach to, 240 is it possible? 61 =Persian rug=, antique (illus.), 167 how made, 167 imitation (illus.), 167 Kurdistan (illus.), 167 where best are made, 167 =Photographs=, of projectiles, 25 =Photography=, resultant from experiments with mirror, 22 =Piano=, pitch, 489 finishing (illus.), 484 why not more than seven octaves, 480 Dulcimer (illus.), 479 spinet (illus.), 480-481 note what it is, 490 sounding board, 488 tuning, (illus.), 484 building case around (illus.), 483 how the music gets into the, 482 clavichord (illus.), 480 instruments, musical, 488 strings, fastening on (illus.), 482 psaltery, 480 sound box, the first, 479 who made the first, 478 hammers (illus.), 483 action regulation (illus.), 484 virginal (illus.), 480-481 first (illus.), 478 tuning fork, 488 polishing (illus.), 484 sounding board, putting on the (illus.), 482 how discovered, 479 lyre, 479 octave, 480 harpsichord (illus.), 480-481 =Pickers=, boy, slate (illus.), 259 =Pictures=, with a fast camera, 39 moving, how made, 369 size of moving film, 370 never seen by the human eye, 31 taken in one five-thousandth of a second, 31 =Pin money=, why they call it? 231 how name originated, 231 =Pistols=, invented in Pistola, Italy, 46 =Plants=, corn, why it has silk? 176 do father and mother plants live together, 176 how they eat, 511 how they reproduce, 175 why do flowers have smells? 176 why they produce leaves, 175 =Plate glass=, (illus.), 246 =Portland Cement=, why called, 95 =Powder=, filling shells, 50 gun-cotton in smokeless, 35 secret of smokeless powder, 35 smokeless, 35 in submarine mines, amount of, 34 =Pressure=, generated in bore of a big gun, 54 inside of a gun at discharge, 33 in gun-barrel, resistance of, 34 of light, on scales, 37 =Primer=, invented by, 47 =Prof. Bell’s= vibrating reed (illus.), 71 =Projectiles=, photographs of, 25 arrival at target, 24 clear of smoke-zone (illus.), 30 smoke-zone, emerging from (illus.), 29 height in air from mortar, 30 impact of, from guns, 28 leaving gun muzzle (illus.), 27 travel faster than sound, 32 velocity of, 33 viewed in transit, 33 weight of, 53 =Proving grounds=, for big guns, (illus.), 53 =Pyro=, used in developing, 23 =Quarry=, cement (illus.), 96 =Quill the=, in writing (illus.), 14 =Quills=, raising geese for, 14 =Rails, steel making=, blast furnace (illus.), 234 blooming mill (illus.), 237 crane, carrying ingot, (illus.), 236 length of, 238 mixer (illus.), 234 molten steel, pouring (illus.), 236 open hearth furnace (illus.), 235 pouring side of open hearth furnace, 235 shrinkage of, 238 soaking pit (illus.), 236 temperature in furnace, 235 =Rain=, where it goes, 222 why it freshens the air, 222 =Rainbow=, cause of, 253 colors in, what makes? 254 ends of, 254 =Rays=, change their course, 38 heat from light, 36 of light, 36 Roentgen, 307 =Rays-X=, what are they? 307 =Reason=, is there one for everything? 200 =Reed=, the (illus.), 12 =Reflection=, in mirror, 22, 91 =Refraction=, changing light rays called, 38 of light, 38 =Reproduction=, of life, in birds, 179 in fishes, 177 in plants, 175 why we must have, 174 =Rifle=, Kentucky, 45 kick of, 47 modern automatic, 47 over-loading, 47 wheel-lock (illus.), 46 =Rifling=, causes rotation of projectile, 32 a big gun (illus.), 60 of a gun, 53 invented in Austria, 46 =Roads=, concrete (illus.), 103 =Roentgen Rays=, 307 =Rope=, breaker (illus.), 360 compound laying machine (illus.), 361 cross-section, 362 draw frame (illus.), 360 drying fiber, 354 Egyptian kitchen (illus.), 354 Egyptians making (illus.), 353 preparing the fiber in (illus.), 359 four-strand (illus.), 362 hackling, 354 hemp (illus.), 356 hemp in warehouse (illus.), 356 knots, 363 lengths, standard, 362 oiling in manufacture, 356 long made by hand, 354 machine (illus.), 358 opening bales of fiber (illus.), 359 preparation room (illus.), 359 scraping fiber (illus.), 354 sliver formation of (illus.), 360 spindles, 355 spinning after turn, 355 =Rope spinning=, after turn, 355 foreturn, 355 splicing (illus.), 364 spreader (illus.), 360 stakes, 355 =Rope walk=, modern (illus.), 357-358 old-fashioned (illus.), 355 =Routine=, of a telephone call (illus.), 68 =Rubber=, automobile tires, 382 biscuit, 377 blisters, 379 blow holes, 379 breaker-strip, 384 calendering, 381 castilloa, 387 cement, 381 crude, 377-378 curing room, 382-383 dryer, 379 fabric, 384 furnishing pneumatic tires (illus.), 386 gathering (illus.), 377 how secured, 377 how are inner tubes made, 385 marketing balls of, 377 mixing, 379 Para, 387 pneumatic tires, 383 pure, why not used, 380 spreading, 381 spreader room (illus.), 383 tapping (illus.), 377 tire building machines (illus.), 385 tires, how made, 378-379-380 tread laying room, 384 tubes, inner, how made, 385 vulcanizing, 384 washing, 378 wild, what is, 387 why not used pure, 380 wrapping room, 386 =Rugs=, designs imitated by machinery, 168 Persian (illus.), 167 Persian, how made, 167 Persian, imitation, 167 Persian Kurdistan (illus.), 167 Persian, where best are made, 167 Tabriz, reproduction (illus.), 168 weaving by machine (illus.), 171 =Rug manufacturing=, carding machine (illus.), 170 examining and repairing (illus.), 173 packing for shipment (illus.), 173 processes, 169-170 weaving by machinery (illus.), 171 wool sorting, 170 =Sadness=, cause of tears, 38 =Salt=, beds, 493 chemical name of, 493 in water, 351 mines, 493 Salt Lake, 493 soda, 493 supply for United States, 493 wells, 493 where it comes from, 493 =Scales=, pressure of light on, 37 =School slates=, where they come from, 495 =Score=, origin of, 26 =Scouring=, wool (illus.), 85 =Scouring and weaving=, in making woolen cloth (illus.), 88 =Screens=, in shot tower, 51 =Sea=, diver, 202 how men go down to the bottom of, 202 navigating on bottom of, 283 time calculated on the, 315 what the bottom looks like, 202 what makes it roar, 401 =Second=, reckoning in millionths of a, 25 pictures taken in one five-thousandth of a, 31 =Seeds=, why plants produce, 175 =Seeing=, why we cannot see in dark, 91 =Sensation=, of sight, 22 =Sensitive=, paper, 23 =Service=, military, U. S., 24 =Shadows=, cause of, 495 =Shell=, sounds in a, 79 =Shells=, filling with powder, 50 inspection of metallic (illus.), 49 putting metal heads on paper, 50 wad-paper in making, 50 =Sheep=, coming out of forest (illus.), 82 first in America, 80 fleece packing, 82 how much wool does a sheep produce? 83 how wool is taken from the, 82 how taken care of, 82 how we get wool off of, 82 industry in America, 80 industry in the colonies, 81 industry in the west, 81 number in the west, 81 shearing, 82 shearing machines, 82 wool-producing, 83 why sheep precede the plow in civilizing a country, 81 =Shield driving=, air lock bulkhead (illus.), 210 caulking the joints (illus.), 214 description of airlocks, 213 erector at work (illus.), 214 erector (illus.), 210 at end of journey (illus.), 216 grommetting the bolts (illus.), 214 grouting (illus.), 214 how it cuts in tunnel building, 212 how they meet exactly (illus.), 215 in tunnel building (illus.), 208 key plate (illus.), 214 curves around (illus.), 216 models of Penna. R.R. tunnel shields (illus.), 212 rear end in tunnel building (illus.), 210 tunnels, front view (illus.), 209 =Ship=, how does a captain steer his, 407 how can it sail under water? 269 =Shoes=, Amazeen skiving machine, 550 assembling machine (illus.), 552 automatic heel loading and attaching machine (illus.), 560 automatic leveling machine (illus.), 559 automatic sewing machine, 555 American made, 547 ancient and modern forms of sandals, (illus.), 543 ancient sandal maker (illus.), 541 beginning of a shoe (illus.), 549 boot developed from the sandal, 544 boots (illus.), 546 channel cementing machine (illus.), 558 channel laying machine (illus.), 559 channel opening machine (illus.), 558 Crakrow or peaked (illus.), 544 which church and law forbade (illus.), 544 description of ancient sandal (illus.), 542 dyeing out machine, 551 different parts come together, 551 duplex eyeletting machine, 550 edge trimming machine (illus.), 560 Ensign lacing machine, 551 evolution cf the sandal to the shoe (illus.), 542 first machine for making shoes, 545 hand method lasting machine (illus.), 553 heel breasting machine (illus.), 560 heel trimming machine (illus.), 560 ideal clicking machine, 550 Inseam trimming machine (illus.), 556 insole tacking, 551 lasting machine (illus.), 553 loose nailing machine (illus.), 559 success of McKay machine, 547 machine that forms and drives tacks, 554 machines which punch the soles of, 559 my lady’s slippers (illus.), 548 placing shank and filling bottom, 556 planet rounding machine, 551 power tip press, 550 pulling over machine (illus.), 552 putting the ground cork and rubber cement in, 556 rolling machine, 551 rounding and channelling machine (illus.), 557 sewing the sole on, 558 slugging machine (illus.), 560 sole laying machine (illus.), 557 Summit splitting machine, 551 upper stapling machine (illus.), 554 upper trimming machine (illus.), 554 welt and turned shoe machine (illus.), 555 welt beating and washing machine, 556 welt sewing machine, 551 what was the first foot covering like? 541 “whipping the cat,” 545 who made the first shoe in America? 545 work performed by heeling machine (illus.), 560 =Shooting tests= (illus.), 48 =Shotguns=, assembling of, (illus.), 48 =Shot pellets=, 51 =Shrinking=, pit for big gun, 59 =Shuttle=, In weaving wool, 86 =Siberian lambs=, in South Dakota (illus.), 80 =Signs=, talking by, 18 =Silica=, mine (illus.), 247 =Silk=, 109 called “bomby-kia,” 110 caring for young worms, 113 culture, 110 drying skeins of, 119 dyeing, 121 first step in manufacture, 119 first used, 109 hatching eggs, 113