7. It can examine the faults in the lines of submarine mines, and

replace mines exploded in action. Abroad, the Nordenfeldt boat has awakened the most interest, and here the American submarine monitor holds the first place. The form of the Nordenfeldt boat is that of a cigar or of an elongated cylinder tapering away to a fine point at each end. The outer case, built of stout steel, is calculated in its construction to resist such a pressure as would enable the boat to descend even beyond a depth of fifty feet, although that is set as the maximum for its diving operations. The cigar shape does not at first sight commend itself, even in the eyes of nautical men, on account of its supposed tendency towards a rolling motion. The experience, however, gained with the boat exhibited for the benefit of naval experts at Carlscrona, in September, 1885, has shown that very good sea-going qualities can be developed in a craft built upon such lines; for this small vessel has weathered more than one gale in the Baltic, to say nothing of the severe storm it encountered at the entrance to the Kattegat when proceeding from Gottenburg to Copenhagen for the experimental trials. This quality results from the fact that each end of the boat forms a tank, which is filled with water, and as there is no extra buoyancy in those directions, and consequently no tendency to lift at those parts as with an ordinary vessel in a sea-way, the vessel rises and falls bodily instead of pitching. It has been found that by going at a moderate speed and taking the seas a point or so on the bows the boat makes very good weather, as the waves, breaking on the snout, sweep over the fore part and expend their force before any portion of them can reach the central section. Steam, which is employed as motive power, is perfectly trustworthy as an agent. There is nothing about its action, or the appliances connected with it, that is beyond the grasp of an ordinary engineer, whereas such can hardly be said as yet in respect either to electricity or the other agencies by which inventors have sought to obtain motion. The difficulty, however, has always been how to retain steam pressure for any great length of time without carrying on combustion. This in the Nordenfeldt boat is secured in the following ingenious manner: A large reservoir or hot-water cistern (marked Q in the plate) is placed in the fore part of the boat, in communication with the boiler. The steam from the latter passes through a number of tubes in the reservoir N, thus raising the temperature of its contents until the pressure stands at the same degree in both. While the boat is at the surface, the maximum pressure once attained, as long as combustion is carried on, supplies quite enough steam both for driving the engines at full speed and for maintaining the contents of the cistern in the proper superheated condition. When the boat is submerged and the furnace doors are closed combustion ceases, and the steam given off by the hot-water in the boiler and cistern is sufficient to keep the engines going for several hours. [Illustration: LONGITUDINAL PLANS OF NORDENFELDT BOAT.] Submersion to the various depths required is secured by the motion of the vertically acting screws, S S, driven by small three-cylinder engines. The boat is so ballasted as always to have spare buoyancy, and while a few revolutions of the screws will send her under water, the arrest of their motion is all that is required to bring her to the surface again. In this arrangement, as even the non-technical reader will readily understand, there is a great element of safety, the rising motion being entirely independent of any machinery which might refuse to act at the required moment. Another advantage is also gained in the ease with which the horizontal position is maintained by regulating the speed of the screws. To assist in keeping this position there is a horizontal rudder or fin, R, at the bows, which, by a very ingenious arrangement of a plumb weight with other mechanism in connection with the steering tower, works both automatically and by hand. The torpedoes are carried on the outside of the boat, as shown at F. They are Swartzkoph or Whitehead, as the case may be, and are released by electrical action under the control of the captain, standing on the platform at P. C is a cupola of stout glass by which a view is obtained occasionally when the boat is running submerged. _Construction Details._—The following are the dimensions of the Turkish boat: length 100 feet, beam 12 feet, displacement 150 tons, speed 12 knots, and coal endurance sufficient for travelling 900 miles. The engines (E) are of the ordinary inverted compound surface-condensing type, with two cylinders, and with 100 pound pressure indicate 250 horse-power. The circulating and air pumps being actuated by a separate cylinder, the main engine is left free to work or not, while a vacuum is always maintained to assist the various other engines with which the boat is fitted. In this respect it should be mentioned that all the engines are specially designed with such valve arrangements as will make the utmost use of the vacuum, it having been found that while the boat is running beneath the surface as much power can be developed below the atmospheric line as above it. The boiler, B, is of the ordinary marine return-tube type, with two furnaces, and the heating surface is about seven hundred and fifty square feet. The tanks at each end of the boat contain about fifteen tons each, and there is a third of seven tons capacity at the bottom of the central compartment for regulating buoyancy. The coal is stored around the hot-water cistern as well as at the sides of the boiler and over the central ballast tank. Three men and the captain can efficiently work this boat, although she may carry a crew of seven, who could remain in her for over seven hours beneath the water without experiencing any difficulty in respiration. No attempt is made as in some systems to purify the atmosphere by chemical means, as it is said to be quite unnecessary. _The Practical Management._—The boat is operated in the following manner: Steam having been raised to the required pressure, the funnel is lowered, and water is let into the ballast tanks to bring the craft down to the proper trim for action. In this condition the screws, S S, are sufficiently under water to obtain the requisite thrust. The boat may still proceed at the surface for some time if the enemy be distant, but the conning-tower should be closed, and the cupola hatch and the furnace doors shut, before there is any chance of discovery. The vertically acting screws being started, the boat is then submerged to the cupola, and continues approaching until, according to circumstances, it becomes prudent to disappear entirely. The direction is taken at the last moment, and maintained by compass until within striking distance, when a torpedo is released, and the boat immediately turns in another direction. In May of this year there was launched at Barrow a Nordenfeldt boat 110 feet in length and 13 feet in diameter. The engines are capable of developing good power, and a speed of 12 knots on the surface was realized. The boat was tried on the Bosporus during July under government supervision, and as these were satisfactory, it seems likely that a number of similar vessels will be built next year for the Ottoman navy. The original submarine monitor _Peacemaker_ is well known through its trials on the Hudson River in 1886, but since then so many improvements have been made in the direction of increased efficiency that it is confidently expected the boat just designed will surpass its former successes. It must be understood in the beginning that its essential principle remains the same, all the important improvements being the outgrowth of the experience gained in previous experiments. Broadly defined, the new craft has a midship section, which through its high centre of buoyancy and low centre of gravity gives great stability of form, or, to make it plain to the non-technical reader, it differs from the ordinary cigar and tortoise shaped boat in being more nearly like the section of a pear, the apex of which forms the keel. Its longitudinal section is not unlike the form generally used, though the lines are such as have been found to give the form of least resistance and the highest speed. It is built of steel, with frames and spacings sufficient to stand the pressure of the lowest depth to which the boat is or can be expected to go. The old dimensions were: length 30 feet, depth 7 feet, and beam 8 feet. In order to obtain increased speed the present vessel will be 50 feet in length, 8 feet in beam, and 8 feet in depth, with a displacement of from thirty-five to forty tons, or an amount sufficient to carry the weights of the interchangeable boiler, of the sixty horse-power engine, and of the provisions and fuel necessary for a surface cruise of one week, and, when necessary, for a constantly submerged cruise of twelve hours. The advantages claimed for the new boat are that she is so self-sustaining as not to need the assistance of any other vessel; that she is not an accessary, but has in herself all essentials of defence; and that she answers all possible necessities for submarine work of any kind whatever, whether in peace or war. The increased speed will, it is hoped, give her power to attack modern vessels under way. When submerged, as was proved last summer, she sent no bubbles of air to the surface, and had neither a wake nor a wash to militate against the possibilities of an absolutely secret attack. Besides these advantages, the boat is said to be a safe surface-cruising vessel, forming no target for the destructive action of an enemy’s attack, and at the same time having a capacity for disappearing so readily under water and avoiding the possibility of discovery that the enemy will be unable to tell when, where, or how the assault upon him may be made. As in a former trial an accident proved the danger of an exposed conning-tower, the Submarine Monitor Company have provided a fin or guard for protecting the new helmsman’s lookout and companion-hatches. The waterlock appliance employed in the original boat has now an additional use in supplying a mode of egress and ingress, the opening being made telescopic, so as to permit surface runs in comparatively rough water. When submerged, the smoke-stack acts telescopically, and is closed with a water-tight valve. To avoid the necessity of divers going out of the boat when under water, there are various openings at places in the exterior skin to which rubber sleeves or arms, with a radius sufficient to cover almost all practical necessities, will be fitted. These apertures do not constitute planes of weakness or danger, because they are normally closed by stout water-tight dead-lights. [Illustration: THE SUBMARINE MONITOR “PEACEMAKER.”] The Westinghouse engine is employed, as its construction prevents, by the packing used, any radiation of heat and the consequent elevation of temperation below. The air-tight doors and bulkheads work laterally, and the conning-dome is made of steel, with such apertures as will enable the helmsman to have, when on the surface, an all-round view, and when submerged, a sufficient light to let him in the daytime read, at a depth of thirty feet, the time by his watch. Should the necessity arise, when submerged, the purity of the atmosphere below is preserved by passing the air through caustic soda, thus eliminating carbonic acid gas, and by reinforcing the loss of oxygen from tanks of compressed air. In the original experiments the boat was frequently submerged six hours at a time, and the crew of two men had no other air supplied than that which the boat carried down with her. Besides these chemical means there are rubber tubes floated by buoys, with nozzles which protrude above the wash of the surface water. There is in each tube an automatic valve, which prevents water coming through the pipe at the time the air is being pumped in, and the depth below the surface to which outside air can be supplied is limited only by the length of the pipe. In the plate, A represents a patented interchangeable boiler, in which either hydro-carbonate fuel or caustic soda can be used, in both cases steam being the motive power. The interior boiler for the use of the caustic soda is surrounded by a jacket, into which the steam exhausted from the engine can be used before it becomes so saturated as to create a back pressure on the engine, that is, for a period of twelve hours. When this limit is attained, and the surface is reached, the soda can be blown off into an outer receptacle provided for the purpose, and then reheated and recharged. The hydro-carbon fuel is ordinary mineral oil, carried in tanks of sufficient capacity for a surface run of a week. It may be emphasized as an important fact that this method of exhausting into the jacket of the boiler avoids the possibility of any bubbles appearing on the surface, as was notably the case with the earlier Lay boats. Before diving, the caustic soda, which has been already heated by the combustion of the oil to the proper degree, acts in place of the ordinary fuel, thus constituting a sort of perpetual motion, until the point of saturation is reached, and back pressure in the engine results. The boat, when on the surface, is run with the oil fuel, but as soon as it becomes necessary to dive this fire is extinguished, the after-hatch is opened by unlocking the door of the bulkhead separating the after from the bulkheaded end of the vessel, and by a system of fans the hot air from the fire-room is driven outboard. Then the after telescopic hatch is reefed and secured, the soda is thrown from the receptacle where it has been heated into the jacket of the caustic-soda boiler, the fires are put out, the smoke-stack is taken in and securely fastened, and the machinist, leaving the engine-room, goes through the bulkhead door into the forward compartment, where he has complete control of the machinery and boiler by means of a duplicate set of gauges and levers. In case of an attack, the man detailed for operating the main torpedo is left in the after compartment, where he has access to that weapon and to the buoy, reel, and other mechanical appliances employed in its operation. The helmsman, who controls the steering apparatus that governs the horizontal and perpendicular rudders, also operates with his feet the levers which are connected by links to the throttle that supplies steam to cylinders K K. These last function like the Westinghouse brake, and are connected with pistons to the cylinders J J. Through their agency water is at will admitted into or forced out of the larger receptacles, either from one end or from both ends simultaneously. The effect of discharging water is of course to increase the buoyancy of the vessel; and of admitting it, to decrease this quality so that without changing structural weights the boat is enabled to rise or sink perpendicularly, or, by admitting more water in one end than in the other, to take a downward or an upward course. Though this does away with the necessity of the horizontal rudder, it is kept as an additional resource for steering. In case of accident to the connecting pipes or machinery the vessel is supplied with water receptacles and hand-pumps, which are able to govern its submergence so that should all other mechanism break down the boat is so completely under the control of the operator that it can at all times be brought to the surface. As an additional safeguard, there is on the outside of the boat a quantity of ballast which can be readily detached by the arms or sleeves previously described, and so effectively that the reserve buoyancy thus gained will alone carry the boat to the surface. In addition to the main torpedo and buoy resting in the cylindrical apertures aft, other torpedoes, connected by spans, are carried on deck. The method of their employment in attack is to go under the body of the vessel athwartship, and to liberate them. As they are fitted with magnets, they will, it is claimed, when freed, attach themselves to the bilges of the enemy’s vessel, while the _Peacemaker_ can continue her cruise and let them act automatically, or, backing off to a distance greater than the depth of water in which she then is, safely explode them by conventional electrical appliances. With the increased speed of the present boat there are various methods of attacking vessels of war when under way, among them one which is somewhat similar to that described above. The _Peacemaker_, when under the body of the vessel athwartship, would liberate a buoy, B, that is connected with a torpedo, T, by a chain, the length of which depends upon the depth beneath the buoy the torpedo is desired to float. The steel tow-line to the torpedo is payed out from reel G to a sufficient length, and then by going ahead with the boat the torpedo is drawn close under the opposite side of vessel from buoy B. In this position the torpedo can be exploded by electricity. If necessary, by liberating buoy B, while crossing the bow on the starboard side of the fore-foot of a vessel, the forward motion will draw the torpedo, T, close in to the opposite side; then, by a system of push-pins on the torpedo, the operator learns that it is in close contact and ready for explosion by electricity. Should the enemy’s vessel be at anchor the tide can be employed for the purpose of bringing the buoy on one side of the vessel while the torpedo is on the other. The boat is supplied with the ordinary incandescent lights, or apparatus for lighting the interior for night attacks. TORPEDOES. America has contributed to modern warfare many of its most valuable inventions. In the decade of 1850-60 the steam frigates of the _Merrimac_ class revolutionized the naval constructions of the world, and became the models for the war-ships of the great maritime powers. In the same period our coast defences reached the high-water mark of modern development, and, soon to be crystallized, there were seething in the brains of American inventors ideas of guns, ships, and projectiles which made history. Though to-day our created contributions to quick peace through arrested or irresistible war are meagre, still many of the theories which make possible modern ordnance and ships are the fruits of American genius and industry. Is the future to be as fertile in thought and deed? Are the destroyers of Ericsson, the dynamite safety shells of Hayes, the guns of Zalinski, the torpedoes of Howell, Sims, or Berdan, the turrets of Timby, the submarine monitors of Tuck, the gun-carriages of King or Buffington, the ordnance of Sicard, Benét—are these to prove that Yankee brain and brawn are potent yet for the mastery of the problem? The country has no plainer duty than to foster by every care American ideas working in national ways of thought. It is rich, public sentiment is ripe and responsive, and Congress should encourage in peace the experiments which may make war impossible. In the question of ship armament and sea-coast fortifications notably, the value of torpedoes is now so generally recognized that the definite selection of some type has attained an importance which demands most careful consideration. All experts agree that they are vital, but there is not that consensus of opinion which within limits affirms exactly what should be done. The Fortification Board in their report say: “It is not generally considered possible to bar the progress of an armored fleet by the mere fire of a battery; some obstructions sufficient to arrest the ships within effective range of the guns is necessary. The kind of obstruction now relied upon is the torpedo, in the form of a submarine mine, and, except in special cases, exploded by electric currents which are so managed that the operator on shore can either ignite the mine under the ship’s bottom, or allow the ship to explode it by contact. In deep channels the submarine mines are buoyant; in comparatively shallow waters they are placed upon the bottom—the object in both cases being to touch or nearly approach the hull of the vessel. Submarine mines are not accessaries to defence, but are essential features wherever they can be applied.” The Senate Committee on Ordnance and War-ships reported: “Concerning another class of torpedoes, ‘fixed’ or ‘anchored’ or ‘planted,’ technically known as submarine mines, there is a great popular misapprehension. Their value is greatly overestimated. They require picked and trained men for their management, electrical apparatus for their discharge and for lighting up the approaches, stations on shore secure against sudden assault, a flanking fire of canister and case shot and of machine guns (themselves protected), light draught picket-boats, and the overshadowing protection of armored forts and heavy guns. None of these things can be extemporized. The submarine mine alone is of little use, and it must accompany, not precede, more costly and less easily prepared means of defence.” There is, however, a more definite agreement as to the value of torpedo-boats. The Fortification Board declare: “Among the most important means of conducting an active defence of the coast is the torpedo-boat, which, although recently developed, has received the sanction of the nations of Europe, each one of which now possesses a large number of these vessels. Their use will be quite general. First, in disturbing blockades, and preventing these from being made close, as no fleet would like to lie overnight within striking distance of a station of these boats; secondly, in attacking an enemy’s ship enveloped in fog or smoke; thirdly, in relieving a vessel pursued by the enemy; and fourthly, in defending the mines by night and by day against attempts at counter-mining, and in many other ways not necessary to recapitulate.” Impressed with the utility of this mode of defence, the Board recommended the construction of one hundred and fifty of these boats, and the organization of a special corps of officers and men from the navy trained to their use. In England, Commander Gallwey does not hesitate to say that the torpedo-boat is for harbor defence so superior to the submarine mine that he would not be surprised if before long it superseded the latter altogether. In France, Charmes insists that an armored vessel will run the most serious risk if a torpedo-boat is allowed to approach unobserved to within one thousand to fifteen hundred feet; that the torpedo will surely triumph over the iron-clad, and that armor has been vanquished, not by the gun, but by the torpedo. A NAVAL RESERVE. Among the problems to be solved by an efficient naval administration there is none more difficult or of greater importance than the formation of reserves of seamen. Our late war exposed the nation’s weakness in sailors. At the beginning of hostilities the fleet, on paper, consisted of forty-two ships of all classes, mainly sailing-vessels, with a few paddle-wheel steamers, and less than ten screw-vessels with auxiliary power. Its _personnel_ comprised seven thousand of all grades. And yet, to blockade a coast of over three thousand miles in length, the Secretary of the Navy had at his disposal but three effective vessels, and a reserve of only two hundred seamen on all the receiving-ships and at all the naval stations. As late as the first of July, 1863, there were not men enough to carry out efficiently the work imposed upon the navy, and of the thirty-four thousand blue-jackets twenty-five thousand were landsmen. Secretary Welles, at the end of the same year, complained that there were no reserve seamen, that the supply for immediate and imperative duties was so inadequate that one of the largest and fastest steamers destined for important foreign service had been detained for months in consequence of the need of a crew, and that many other vessels were very much short of their complements. The cause of this was want of foresight, of prudence, of national common-sense even. We did not lack the material from which crews could have been drawn, for in 1860 over seventy-five thousand men sailed in the American merchant marine, fifty thousand of whom, under any system of enrolment suited to our national instincts and prejudices, would, before the end of 1861, have been available for duty on shipboard. In peace there had been no organization, so when war came we were almost helpless, and as late as the end of 1863 not twenty per cent. of the men who should have been ready for service were in government ships. Let _doctrinaires_ theorize as they may, this was not the fault of our maritime class, for thousands of sailors and fishermen who had already entered the army were by force of law denied the opportunity either of enlisting in, or of being transferred to, the navy. In addition, the operation of the draft was made detrimental to the naval interests of the country, for it violated the Act of May, 1792, which exempts from military duty all mariners actually employed in the sea service of any citizen or merchant within the United States. Furthermore, the government unjustly discriminated against the seaboard towns, for not only was the seafaring class, which is fostered and cherished by all maritime governments, withdrawn from the element to which it has been accustomed, but in addition sailors actually afloat were taken from their ships and compelled, under the penalty of law, to enter the land service. It was not until 1864 that Congress finally enacted the law which enabled seamen serving as soldiers to be drafted into the navy. How different would have been the state of affairs had there existed in 1861 some system of government administration as to the creation of naval reserves, or, more far-reaching still, had we been free from that illogical distrust which possessed the whole country! The fear of too much centralization was the stock in trade of professional patriots, and the people, hampered by traditions which had come down to us from our English ancestors, saw in any attempt towards efficient war preparation in times of peace all the dangers they had been taught to believe existed in standing armies. England acted more wisely, for she had been taught a grim lesson by her adversities, and without fear we might have profited by her example. In the history of the Peninsula war, Napier, after picturing the horrors of the fearful April night when Badajoz was stormed, asked, bitterly, “And why was all this striving in blood against insurmountable difficulties? Why were men sent thus to slaughter when the application of a just science would have rendered the operations comparatively easy? “Because the English ministers, so ready to plunge into war, were quite ignorant of its exercises; because the English people are warlike without being military, and, under the pretence of maintaining liberty which they do not possess, oppose in peace all useful martial establishments. In the beginning of each war England had to seek in blood for the knowledge necessary to insure success.” Equally has this always been the attitude of the American people towards every attempt made in peace to prepare for war. Besides this national distrust, prejudices had to be overcome which have existed both in the navy and the merchant marine. Our naval officers have never made any determined effort to create a reserve, either because they have not fully grasped the correlation and interdependence of the navy and the merchant marine, or because they have doubted the wisdom of spending upon an outside issue appropriations which, given to the navy, would produce a more immediate and tangible result. But from both points of view they are wrong, “for a navy unsupported by a merchant marine is a hot-house plant which may produce great results for a while, but cannot endure the strain of a long protracted campaign.” From the merchant marine the _personnel_ of the navy in war must come, and it is a fallacy to believe that by a small addition to our ordinary naval resources we would be able to cope with the navies of other maritime powers, or that in a long war an efficient and numerous reserve is not of greater importance than a few more seamen permanently maintained in the navy during peace. To the merchants and ship-owners the question is one of vital importance. The earliest and most disastrous consequence of war will fall upon the shipping interest. Under any system of defence the necessities of the navy must withdraw seamen from the merchant service and raise the rate of wages. If, then, by timely precautions during peace, we can diminish the probability that war can occur at all; if we are ready upon the outbreak of war to show that our homeward-bound ships are safe; if we can abolish or modify the risk that the employment of seamen would be abruptly suspended by embargo or interfered with by impressment or draft; if we can attach the sailor to his country, and prevent him from seeking employment under other flags, surely the owners of our ships and merchants will reap the greatest advantage. Abroad the importance of the subject has been fully recognized. France, under a system which has existed for over two hundred and fifty years, maintains a reserve of 172,000 men, who are between the ages of eighteen and fifty; 65,000 of these are between the ages of twenty and twenty-six, 15,000 are usually kept afloat, and 6000 more are quartered on shore. Germany has 15,000, and England nearly the same number. Notwithstanding the decadence of our shipping interest we have a large force from which to draw. The maritime population of this country numbers over 350,000, of whom 180,000 are available for the fleet. This number of course includes all those in any way connected with sea industries, and embraces coasters, fishermen, whalers, yachtsmen, boatmen, and all workmen in ship-building yards and equipment shops and stores. To man our ships in time of war three means are open: voluntary enlistment, draft or impressment, or employment of men enrolled in a naval reserve. It would be unreasonable to depend altogether upon the loyal and unselfish patriotism of necessitous men serving before the mast, and there is a chance that mere enthusiasm would not induce a seaman to join the navy if employment was being offered elsewhere at increasing rates of pay. Impressment under any name is unpopular. In its common form it is illegal, and the draft is ever a last resort and always a dangerous measure. Nothing, then, remains as a certainty but to turn towards the naval reserve as the best means of manning our fleet. In time of war not only would the men enrolled come forward willingly and be immediately available, but deserters would have the machinery of the law put in motion for their apprehension, and popular feeling would be as earnest in support of their arrest as it would be opposed to all attempts which enforced the arbitrary powers of draft or impressment. No system exists abroad entirely suited to our necessities and our national instincts; but, generally speaking, that adopted in England comes nearest to what we should employ. Naturally our lake sailors, coasters, fishermen, and yachtsmen would form the main body of the reserve. These should be enrolled, divided into classes, be given each year a certain fixed sum of pay, with an increase for each day’s drill, and at stated times they should be embarked for great gun practice at sea, so they might learn something of man-of-war routine and discipline. The officers could be drawn from the merchant marine, from the graduates of the school-ships, and from former officers of the regular and volunteer services who are now in civil life. FORCED DRAFT. The subject of forced draft is of great importance, and, as a corollary of high-speed development, is being studied with keen interest. There are wide differences of opinion not only as to the proper systems, but even as to the value of the principle. The literature as yet is rather meagre, but an excellent compilation of existing material will be found in the latest publication of the Naval Intelligence Office. “A forced draft in the furnaces,” explains the _Marine Engineer_ of September, 1887, “can be generated in two ways: first, by exhausting the uptakes and funnels of the products of combustion, when a greater flow of air will necessarily take place through the fire-bars; and secondly, by increasing the pressure of the air in the furnaces beyond that of the atmosphere. The steam-blast in marine boilers is well known to engineers as a means of quickly getting up the steam after its pressure has dropped; but the locomotives on our railways afford a very good illustration of how boilers may be continuously worked under forced combustion through a jet of steam exhausting the smoke-box and funnel of the products of combustion. This system of creating a draft involves a very large expenditure of steam and water, and as it is a _sine qua non_ in these days of high pressure that only fresh water should be used in boilers, and also as only a limited supply of this element can be carried in a ship, it follows that the plan of inducing a forced draft by means of a steam jet in the funnel cannot be well adopted in marine boilers. “Mr. Martin, the inventor of the well-known furnace doors, substitutes a fan in the uptake for the steam jet, and so arranges his funnel that in the event of the forced draft not being required the gases of combustion arising from natural draft will not be impeded in their exit to the atmosphere. He claims for his invention that it does away with all necessity for closing in the stoke-holds or furnaces, and that in war-ships funnels could be dispensed with, as the gases and smoke could be discharged anywhere from the fans. He also claims that by his plan of producing a draft the boiler-tubes become much more efficient as heating surfaces, and that the ends of the tubes in the fire-box are not so liable to be burned away, and that therefore there will be less chance of the boiler leaking round the tubes. There appears to be some grounds for these latter assumptions, for it is a well-known fact that the tubes of locomotive boilers, which are worked, as we have seen, on the exhaust principle, do very much more work than those of marine boilers before they are ferruled or rolled. It can also be shown by a very simple experiment that when the gases are sucked or drawn through the tubes the flame extends a much greater distance along the tube than when the gases are driven through the tubes. In this latter case the flame impinges on the tube-plates before separating into tongues and entering the tubes; but when sucked through the tongues of flame commence at some little distance from the plate before penetrating the tubes, and the ends are not therefore burned as when the flame impinges directly on them. It may be urged, however, against Martin’s system that owing to the greatly increased volume of the products of combustion due to their temperature, fans of from three to four times the size of those used in other systems are required; also, that the uptakes have to be made larger and heavier to take in the fans; and lastly, that the fans themselves are likely to be quickly rendered inefficient through working in a temperature of at least a thousand degrees. These objections prove so formidable that up till the present time Martin’s plan of creating a forced draft has made little or no headway. “The other plan for creating an artificial draft in marine furnaces is to force air into them by means of fans. This is done either by closing in the whole of the stoke-hold and filling it with air of a pressure greater than that of the atmosphere, or by pumping the air direct into the furnace. This latter is the usual practice in the mercantile marine, where economy of fuel is sought after. Mr. Howden seeks, by first heating the air, and then forcing it by means of fans into the furnaces and ash-pits, to insure a very rapid and complete combustion of the coal. His plan has been carried out in the Atlantic liner _Ohio_ quite recently, and the results as published lead one to expect that with a little more progress in the direction in which he is working our ships will be driven across the Atlantic without the expenditure of any fuel whatever. The fact of heating the air to a temperature of two hundred degrees before it enters the furnace cannot go very far in affecting either the rapidity or the completeness of the combustion of the fuel, and it certainly cannot affect the economy. Where the fire-grate area is small compared with the total heating surface, good evaporative results are likely to be obtained; and in the _Ohio_ the fire-grate area was certainly smaller than is usual for the same sized boilers fitted with forced draft. The trip of the _Ohio_ to America has given somewhat different results to those of the official trials, and it is a question whether any saving in weight, either in the apparatus required to produce forced draft under this system, or in the economy of fuel to be derived from it, has been obtained more than exists in the system of closed stoke-holds. “The only plan that seems to hold its own is the closed stoke-hold system, and the results that have been obtained with it in the navy are so satisfactory that Messrs. J. & G. Thomson are about to adopt it in the two large Inman liners they are now building; and also several other firms are about to introduce it in preference to all other plans for increasing the efficiency of their boilers and promoting greater economy. In the Royal Navy space and weight are of such vital importance that the boilers have to be constructed on principles the very reverse of those which exist in boilers specially designed for high evaporative work per pound of fuel; and it is not, therefore, to be wondered at that the consumption of fuel per indicated horse-power has not been reduced since the introduction of forced draft; but, on the other hand, the capabilities of the boilers have been expanded far beyond the expectations of a few years ago. In the mercantile marine there is no reason whatever why the system of closed stoke-holds for creating a forced draft should not combine economy with greater efficiency in the boilers.” These conclusions are not universally accepted, as will be seen in the following extract from the article contributed by Assistant Engineer R. S. Griffin, United States Navy, to the Naval Intelligence Office publication mentioned at the beginning of this subject. “The forced-draft trials of the _Archer_ class,” he writes, “go far towards sustaining the objections raised by Mr. Howden against the closed stoke-hold system. The trials of the _Archer_, _Brisk_, and _Cossack_ had to be discontinued on several occasions, owing to leakage of the boiler-tubes; and when it is remembered that these trials are for only four hours, and that no provision is made for hoisting ashes, it becomes a question of serious consideration whether the maintenance of this high power for such a short period brings with it advantages at all comparable with the continued development of a reasonably high power with an economical expenditure of coal, such as is possible with the closed ash-pit system. “A number of steamers have been fitted with Howden’s system during the past year, among others the _Celtic_, of the White Star Line, and the _Ohio_, of the International Navigation Company. One of the latest steamers fitted with this system is the _City of Venice_, whose engines were converted from compound to quadruple expansion. Her boilers were designed to develop 1800 indicated horse-power with eighty square feet of grate, but on trial she could only work off 1300 indicated horse-power, owing to some derangement of the valves. She was afterwards tried with half the grate surface in use, when it was demonstrated that there would be no difficulty in developing the power so far as the boilers were concerned. Unfortunately, no data as to weight of boilers, space, or heating surface are obtainable. “In 1886 the _Alliance_ was supplied with new boilers, fitted with a system of forced draft designed by the Bureau of Steam Engineering. It was originally the intention of the Department to put six boilers in this vessel, as in the _Enterprise_ and _Nipsic_, but with the introduction of the forced-draft system, which was purely experimental, this number was reduced to four, having a total grate surface of 128 square feet. The boilers were designed to burn anthracite coal with natural draft, and were of course unsuited to the requirements of forced draft, the ratio of heating to grate surface being only 25.6 to 1, and the water surface and steam space being small. The maximum indicated horse-power developed on trial was 1022, but any attempt to run at this or at increased power for any length of time was attended with so much priming of the boilers that the trial had to be discontinued. Alterations were made in the boilers to prevent the priming, but no continuous trial was had previously to the sailing of the _Alliance_. The results obtained on a measured base were, however, sufficient to demonstrate the practicability of the system, and to show that a higher power could be maintained with the four boilers at forced draft than with the original eight boilers at natural draft. “The practical working of the system at sea presents no difficulty, as a recent run of the _Alliance_ has demonstrated. On a continuous run of ten hours, using only two boilers with sixty square feet of grate (the grate surface of each boiler having been reduced to thirty), the mean indicated horse-power was 668 and the maximum 744, being respectively 11.1 and 12.4 indicated horse-power per square foot of grate. There was an entire absence of priming, and no difficulty was experienced in operating the forced-draft apparatus, the length of the trial having been determined by the arrival of the vessel in port. The coal burned was Welsh, of fair quality, the consumption being 29.9 pounds per square foot of grate. “The efficiency of the system may be judged by the results obtained from an experimental boiler at the Washington Navy-yard. The boiler was of the marine locomotive type, and had a ratio of heating to grate surface of 32.73 to 1, with a water space of 245 and a steam space of 163 cubic feet. The coal burned was ordinary Cumberland Valley bituminous, and the evaporation, when burning as much as forty pounds per square foot of grate, was 6.61, while with 37.5 it was 7.24, and this with a moderate air pressure—1.5 inches in ash-pit and one inch on furnace door.” It is unfair to attempt the explanation of this system without accompanying drawings, but it may be stated that the air, drawn by fan-blowers from the heated portion of the fire-room, is forced through a passage into the ash-pit and furnace, a portion of the current being directed by an interposed plate through the holes in the furnace frame. By the agency of a double row of holes the greater portion of the air which enters the furnace passes around the frame, thence through other apertures to the space between the furnace door and lining, and finally to the furnace through the space between the lining and furnace frame. The supply of air when firing or hauling ashes is shut off by a damper. APPENDIX II.[61] THE QUESTION OF TYPES. The following letter appeared in the _Times_ (London) of April 4, 1885: “SIR,—May I request the favor of space in the _Times_ in which to comment upon the opinions recently expressed by Sir Edward Reed and other writers respecting the designs of the _Admiral_ class of ships in the Royal Navy, and the four central-citadel ships which were laid down subsequently to the _Inflexible_? “Having been closely associated with Mr. Barnaby in the designing of all these ships, with the exception of the _Ajax_ and _Agamemnon_, I can speak with full knowledge of both the history and intentions of the designs. “Moreover, my share of the responsibility for the professional work involved in those designs remains, although my official connection with the constructive department of the Admiralty was severed years ago. It need hardly be added that the remarks which follow simply embody my own opinions, and that I write neither as an apologist for Mr. Barnaby nor as a champion of the ship-building policy of the Admiralty. “The sweeping condemnation which has been pronounced against the most recent English battle-ships is based upon the consideration of one feature only in their fighting efficiency, _viz._, the extent of the armor protection of their sides in the region of the water-line. There has been no discussion in the letters to which I have referred of the comparative speeds, armaments, or other qualities of the French and English ships. But the fact that the French ships are armor-belted from end to end, while the English ships have no vertical armor on considerable portions of the length at the region of the water-line, is considered by Sir Edward Reed so serious a matter that he says, ‘The French armored ships must in all reason be expected to dispose of these English ships in a very few minutes by simply destroying their unarmored parts.’ “From this opinion I most strongly dissent, for reasons which are stated below; and I venture to assert that if attention is directed simply to the possible effects of gun-fire, while the possibly greater risks incidental to attacks with the ram and torpedo are altogether neglected, then there is ample justification for the belief that the English ships of recent design can do battle on at least equal terms with their contemporaries in the French or any other navy. “In all recent armored ships, if the wholesale and extremely rapid destruction of the unarmored portions of the ships which Sir Edward Reed contemplates actually took place, very considerable risks would undoubtedly result; but in my judgment these risks are not sensibly affected by the different distribution of the armor on the ships of the two great navies. And, further, there is every reason for doubting whether such wholesale destruction of the unarmored parts could be effected with the appliances which are now available, not merely in ‘a few minutes,’ but in a very considerable time, and under the most favorable conditions for the attack. Nor must it be forgotten that armor, even of the greatest thickness, applied to the sides or decks of ships is not impenetrable to the attack of guns already afloat, while the _mitraille_, which is driven back into a ship when armor is penetrated, is probably as destructive as any kind of projectile can be, and attacks directly the vital parts which the armor is intended to protect. “In support of these assertions I must ask permission to introduce certain detailed statements which appear to be absolutely necessary to a discussion of the subject, but which shall be made as brief and untechnical as possible. “It appears that the points raised by the discussion may be grouped under two heads. First, does the shortening of the belt in the English ships introduce such serious dangers if they have to do battle with the French ships? Secondly, what should be considered the principal uses of armor-plating in modern war-ships? The second question may be considered to include the first; but it will be convenient to take the questions in the order in which they have been placed, as, after all, the greatest immediate interest centres in the comparison between existing ships. “At the outset it is important to remark that in the most recent designs of armored ships for all navies, increase in speed, armament, and thickness of armor has been associated with a decrease in the area of the broadside protected by armor. Further, it has been considered important in most cases to distribute the armored positions of the heavy guns in the ships in order to reduce the risks of complete disablement of the principal armament by one or two lucky shots which may happen when the heavy guns are concentrated in a single citadel or battery. This distribution of the heavy guns also gives greater efficiency to the auxiliary armament of lighter guns, and enables these heavy guns to be placed at a considerably greater height above water than was usual in former days, so that the chances of the guns being prevented from being fought in heavy weather are diminished, and their power as compared with the lower guns in earlier ships is increased, especially when firing with depression. “The days of the ‘completely protected iron-clad,’ with the broadside armored throughout the length from the upper deck down to five or six feet below the water-line, have long gone by. The ‘central battery and belt’ system has also been practically dropped, whether the battery contained broadside guns or formed a citadel protecting the bases of the turrets. In short, on modern battle-ships there now remains only a narrow belt of armor, rising from five or six feet below the load-line to two or three feet above it. This narrow strip of armor in the French ships extends from end to end, and is associated with a protective deck worked at the height of the top of the belt, and forming a strong roof to the hold spaces beneath. In the English ships of the _Admiral_ class the belt of armor extends somewhat less than half the total length, protecting one hundred and forty to one hundred and fifty feet of the central portion of the ship (in which are situate the engines and boilers), and protecting also the communications from the barbette towers to the magazines. At the extremities of the belt strong armored bulkheads are built across the ships. The protected deck is fitted at the upper edge of the belt over the central portion. Before and abaft the bulkheads, where there is no side armor, the protection consists of a strong steel deck, situated from four to five feet below water, and extending to the bow and stern respectively. Upon this under-water deck are placed coal-bunkers, chain-lockers, fresh-water tanks, store-rooms, etc., the spaces between it and the deck next above being subdivided into a large number of water-tight compartments or cells by means of longitudinal and transverse bulkheads. A water-tight top or roof to these compartments is formed by plating over the main deck-beams with thin steel at the same height above water as the top of the armor-belt. In this manner the unarmored ends above the protective deck are not merely packed to a large extent with water-excluding substances when the vessel is fully laden, but they are minutely subdivided into separate compartments, which can only be thrown into communication with one another by means of very extensive injuries to the partitions. “In all the modern French ships, as well as in the _Admiral_ class, a light steel superstructure of considerable height is built above the level of the belt-deck; the living quarters of the crew and the stations of the auxiliary armament are contained within this light erection, which also surrounds the armored communications from the barbette towers to the magazines. In this manner a ship with a small height of armored freeboard is converted into a high-sided ship for all purposes of ordinary navigation, sea-worthiness, and habitability; while spaces are provided in which a more or less considerable number of light guns can be fought concurrently with the heavy guns placed in the armor-protected stations. The radical difference, therefore, between the French ships and the _Admiral_ class, independently of other considerations than the armor protection of the water-line, consists in the omission of the side armor at the extremities, and the use instead of the side armor of the strong under-water deck with cellular subdivision and other arrangements for adding to the protection and securing the buoyancy of the spaces at the ends, into which water may find access through the thin sides if they are shot through and seriously damaged in action. If the completely belted French ship has to fight a vessel of the _Admiral_ class, the latter has obviously the greater chance of damage to the narrow strips of the sides lying above the under-water deck before and abaft the ends of the belt. If the action takes place in smooth water, when the ships are neither rolling nor pitching, but are simply in motion, the chances of hitting these narrow strips in the water-line region might not be very great; but it must be admitted that even the lightest guns would penetrate the thin sides of the English ships and admit more or less considerable quantities of water into the ends. If, on the other hand, the fight takes place in a sea-way, with the ships lolling and pitching, then the relative importance of penetration of these narrow’ strips of the ends of the English ships becomes much less, because the belt armor of the French ships will be brought out of water for a considerable length of the bow and the stern by a very moderate angle of pitching, or by the passage of a comparatively low wave, and because rolling motion of the ships will alternately immerse or emerge the belt armor, even at the midships part, where it has its greatest thickness. In fact, as I have more than once said publicly, it is clearly an error to limit criticism to the longitudinal extent of the belt armor in modern ships, and to exclude consideration of the vertical extent of the armor above and below the load-line. Apart from any discussion of the question from the artillerist’s point of view, or any attempt to determine the probability or otherwise of the wholesale destruction of the unarmored portions of modern battle ships by shell-fire from large guns, or by the projectiles from rapid-firing and machine guns, it is perfectly obvious to any one who will examine into the matter that the risk of damage to the light superstructures situated above the belt must be greater than the corresponding risk of damage to the narrow strips of side area exposed at the unarmored ends of the _Admiral_ class, between the level of the belt-deck and the water-line. “Sir Spencer Robinson, after his inspection of the models shown him at the Admiralty, recognizes the fact that in the French belted ships (of which the _Amiral Duperré_ is an example), if the light sides above the belt-deck are destroyed or very seriously riddled in action, the ship would be capsized in a very moderate sea-way. He further emphasizes the statement that the ships of the _Admiral_ class in the English navy, if similarly treated, would also capsize under the same conditions, and he appears to be surprised at the admission having been made. The fact is that there has never been any assertion that the _Admiral_ class would be safe against capsizing independently of assistance given to the armor-belted portions by the unarmored structure situated above. On the contrary, from the first, in the design of these ships, it was recognized that their stability, in the sense of their power to resist being capsized, if inclined to even moderate angles of inclination, was not guaranteed by the armor-belts. In this respect they were in identically the same position as all other armored ships with shallow water-line belts and isolated armored batteries placed high above water. “What has been said respecting the _Admiral_ class is this: If the unarmored ends above the protective deck were completely thrown open to the sea, then the initial stability (that is to say, the stiffness of the ships or their power to resist small inclinations from the upright) would still be guaranteed by the central armored portions. So fully did we appreciate the fact that the life of the ship in action (as determined by her power to resist large inclinations) depends greatly upon the assistance given by the unarmored superstructures to the armor-belted parts, that we were careful to make the structural arrangements of the superstructures above the belts such that they could bear a very considerable amount of riddling and damage from shot and shell without ceasing to contribute in the most important degree to the buoyancy and stability. “There are double cellular sides between the belt and upper decks; the main bulkheads are carried up high above water; hatches and openings are trunked up and protected by coffer-dams. In short, every possible precaution is taken to subdivide into compartments, and thus limit the spaces to which water can find access when the outer sides are penetrated or shattered, as well as to facilitate the work of stopping temporarily shot-holes in the sides. “Now, without in the least intending to discredit the work of the French designers, I have to state that no corresponding or equal precautions have been taken in the portions of their ships lying above the belt-decks. And the absence of these features in the French ships is a great relative advantage to the English ships. Of course there is nothing to hinder the French from imitating our practice, but they are content to take the risks involved in a simpler construction, and in so doing they show their practical disbelief in the doctrine of armor-protected stability. I am aware that some eminent authorities do not concur with this view, and maintain that stability and buoyancy should be guaranteed by armor. To this point I will revert hereafter, but for the present I am content to say that, as between the French ships and the _Admiral_ class, the most serious risks of damage by gun-fire in action are of the same kind, and, practically, are not affected by the shortening of the armor-belts in the English ships. “Next I would refer to the differences which are undoubtedly involved in shortening the belts of the English ships. In the first place, by dispensing with the side armor towards the extremities a very considerable saving is effected in the weight and the cost of the armor fitted to the ships. Mr. Barnaby has recently given an illustration of this, where a ship, in other respects unchanged, has to be increased from 10,000 to 11,000 tons in displacement in order to carry the shallow armor-belt to the ends. In the _Collingwood_ herself quite as large a proportionate increase of size would be involved in having a thick armor-belt from stem to stern. This saving in weight and cost of armor might, of course, be purchased too dearly, if dispensing with the armor involved possibly fatal risks to the ship. However the result may be attained, there is universal agreement that a ship-of-war should have her buoyancy, stability, and trim guaranteed as far as possible against the effects of damage in action. Now, in the _Admiral_ class this matter was very carefully investigated before the design was approved. In order to prevent derangement of the trim of the vessels by penetration of the light sides above the protective deck at one end, arrangements were made in the design by means of which water can be introduced into the spaces occupied by coal-bunkers, etc., before the ships go into action. “The extent to which water may be introduced is a matter over which the captain would necessarily have control. But even if the whole of the unoccupied spaces were filled with water, the increase in draught would not exceed fourteen to eighteen inches, and the loss in speed would not exceed half a knot. If only the coal-bunkers were flooded as a preliminary to action, the chance of any serious disturbance of trim, and consequent loss of manœuvring power or speed by damage to the light sides above the protective deck and near the water, would be very small, and the ‘sinkage’ of the vessel would be decreased considerably. But taking the extreme case, with the ends completely filled and a sinkage of fourteen to eighteen inches, a ship of the _Admiral_ class would go into action with practically her full speed available, and with her ends so protected by under-water deck and the water admitted above that deck that damage to the thin sides by shot or shell penetrating at or near the water-line would not produce changes of trim or alterations of draught to any greater extent than would be produced if the armor-belt had been carried to the stem and stern. Nor would the admission of water into the ends render the vessel unstable. “It has been urged that the sinkage due to filling the tank ends with water is a disadvantage, because it brings the upper edge of the belt armor in the _Admiral_ class about fourteen to eighteen inches nearer the water than the upper edge of the belts of the French ships. If the greatest danger of the ships was to be measured by the smallness of their ‘reserve’ of ‘armor-protected buoyancy’ (that is to say, by the buoyancy of the part of the ship lying above her fighting water-line and below the belt-deck), then the _Admiral_ class would not compare favorably with the fully belted French ships. But I have already explained that this is not the true measure of the greatest danger arising from the effects of gun-fire, and that it would be a mistake to assume that in either the French or the English ships the armor-belted portions of the vessels guarantee their safety when damaged in action. “As between the _Admiral_ class and the central-citadel ships of the _Inflexible_ type there is a difference in this respect which has been much commented upon. When the ends of the citadel ships are filled with water, the armored wall of the citadel still remains several feet above water; whereas, in the _Admiral_ class, the top of the belt under similar conditions is very near the water-level. All that need be said on this point is that, notwithstanding the greater height of the armored wall above water, the citadel ships have practically no greater guarantee of safety against capsizing by means of armor-protected stability than the _Admiral_ class. In both classes the armored portions require the assistance of the unarmored to secure such a range and amount of stability as shall effectually guarantee their security when damaged in action. And, as has been stated above, this condition is true of all armor-clads with narrow armor-belts. “One other objection to the shortened belts yet remains to be considered. “It is urged that when the thin ends are broken through or damaged by shot or shell, jagged or protruding holes will be formed in the plating near the water-line, and then if the ships are driven at speed, the water will flow into the holes in large quantities, and produce serious changes of trim and loss of speed. In support of this contention, reference is made to the published reports of experiments made with the _Inflexible’s_ model about eight years ago. It is impossible to discuss the matter fully, and I must therefore content myself with a statement of my opinion, formed after a careful personal observation of these model experiments. First, it cannot be shown from the experiments that the presence of a shallow belt of armor reaching two to three feet above the still-water line would make any sensible difference in the dangers arising from the circumstances described. Holes in the thin sides above this belt would admit water in large quantities on the belt-deck when the vessel was under way, and if it could flow along that deck changes of trim and other disagreeable consequences would result. Secondly, it is certain that the numerous bulkheads and partitions, coffer-dams, etc., built above the belt-deck level in the _Admiral_ class for the very purpose of limiting the flow of entering water would greatly decrease any tendency to check the speed or change the trim. Whether the belt be short or long, it is evident that gaping holes low down in the light sides will make it prudent for a captain to slow down somewhat if he wishes to keep the water out as much as possible. But between such prudence and the danger of disaster there is a wide gulf. “Summing up the foregoing statements, I desire to record my opinion, based upon complete personal knowledge of every detail in the calculations and designs for the _Admiral_ class, that the disposition of the belt armor (in association with the protective decks and cellular sides, water-tight subdivision, etc., existing in the unarmored portions of the vessels situated above the protective decks) is such that the buoyancy, stability, trim, speed, and manœuvring capabilities are well guaranteed against extensive damage from shot and shell fire in action. And, further, that in these particulars the _Admiral_ class are capable of meeting, at least on equal terms, their contemporary ships in the French navy. “I must add that I am not here instituting any comparison between the ‘fighting efficiencies’ of the ships of the two fleets; nor have I space in this letter to do so. Opinions have differed, and will probably always differ, as to the relative importance of the different qualities which go to make up fighting efficiency. There is no simple formula admitting of general application which enables the comparative fighting values of war-ships to be appraised. As the conditions of naval warfare change and war material is developed, so the balance of qualities in ship-designing has to be readjusted, and estimates of the fighting powers of existing ships have to be revised. And, further, different designers, working simultaneously, distribute the displacement, which is their sum total of capital to work upon, according to their own judgments of what is wisest and best for the particular conditions which the ships built from those designs have to fulfil. The designer who has the larger displacement to work upon has the better opportunity of producing a more powerful ship; but it by no means follows that he will secure so good a combination of qualities as a rival obtains on a smaller displacement. And hence I cannot but dissent from the doctrine that displacement tonnage is to be accepted as a fair measure of relative fighting efficiency, or that recent English ships are necessarily unable to fight recent French ships because they are of smaller displacement. “In the preceding remarks I have been careful to confine myself chiefly to the naval architect’s side of the subject, as it would clearly be out of place for me to say much respecting the artillerist’s side. But, having had the great advantage of knowing the views of some of the most experienced gun-makers and gunnery officers, and having studied carefully what has been written on the subject, I would venture to say a few words. “First, there seems, as was previously remarked, every reason for doubting, in the actual conditions of naval gunnery, whether it would be possible, not merely in a few minutes, but in a considerable time, to produce the wholesale destruction of the unarmored parts of modern war-ships which has been assumed in the condemnation of the _Admiral_ class. If the _Collingwood_, or one of her successors, were simply treated as a moving target in a sea-way for the _Amiral Duperré_ or one of her consorts, this would be a most improbable result. But, remembering that the _Collingwood_ would herself be delivering heavy blows in return for those received, the chances of her disablement would necessarily be decreased. Secondly, it does not seem at all evident that the