875. On the other hand, Sturm says, in that part of the Ritterplatzes

which relates to architecture, p. 18: “An archduke at Florence discovered again the art of working porphyry, but suffered it to die with him in the year 1556.” [825] Florillo Gesch. der Zeichnenden Künste, 8vo, i. p. 461. [826] Art de convertir le Fer en Acier, p. 245. [827] Stephanus de Urbibus, under the word Λακεδαίμων, p. 413. [828] Clemens Alexandr. in Pædagog. ii. p. 161, edit. Cologne, 1688, fol. says, speaking of luxury, “One can cut meat without having Indian iron.” [829] Philos. Transact. 1795, ii. p. 322. [830] [The manner in which iron ore is smelted and converted into wootz or Indian steel, by the natives at the present day, is probably the very same that was practised by them at the time of the invasion of Alexander; and it is a uniform process, from the Himalaya Mountains to Cape Comorin. The furnace or bloomery in which the ore is smelted, is from four to five feet high; it is somewhat pear-shaped, being about two feet wide at bottom and one foot at top; it is built entirely of clay, so that a couple of men may finish its erection in a few hours, and have it ready for use the next day. There is an opening in front about a foot or more in height, which is built up with clay at the commencement, and broken down at the end, of each smelting operation. The bellows are usually made of a goat’s skin, which has been stripped from the animal without ripping open the part covering the belly. The apertures at the legs are tied up, and a nozzle of bamboo is fastened in the opening formed by the neck. The orifice of the tail is enlarged and distended by two slips of bamboo. These are grasped in the hand, and kept close together in making the stroke for the blast; in the returning stroke they are separated to admit the air. By working a bellows of this kind with each hand, making alternate strokes, a tolerably uniform blast is produced. The bamboo nozzles of the bellows are inserted into tubes of clay, which pass into the furnace at the bottom corners of the temporary wall in front. The furnace is filled with charcoal, and a lighted coal being introduced before the nozzles, the mass in the interior is soon kindled. As soon as this is accomplished, a small portion of the ore, previously moistened with water, to prevent it from running through the charcoal, but without any flux whatever, is laid on the top of the coals, and covered with charcoal to fill up the furnace. In this manner ore and fuel are supplied, and the bellows are urged for three or four hours, when the process is stopped, and the temporary wall in front broken down; the bloom is removed with a pair of tongs from the bottom of the furnace. In converting the iron into steel, the natives cut it into pieces to enable it to pack better in the crucible, which is formed of refractory clay, mixed with a large quantity of charred husk of rice. It is seldom charged with more than a pound of iron, which is put in with a proper weight of dried wood, chopped small, and both are covered with one or two green leaves; the proportions being in general ten parts of iron to one of wood and leaves. The mouth of the crucible is then stopped with a handful of tempered clay, rammed in very closely, to exclude the air. As soon as the clay plugs of the crucibles are dry, from twenty to twenty-four of them are built up in the form of an arch in a small blast furnace; they are kept covered with charcoal, and subjected to heat urged by a blast for about two hours and a half, when the process is considered to be complete. The crucibles being now taken out of the furnace and allowed to cool, are broken, and the steel is found in the form of a cake, rounded by the bottom of the crucible.--Ure’s Dictionary of Arts and Manufactures, art. STEEL.] STAMPING-WORKS[831]. In order to separate metallic ores from the barren rock or stones with which they occur, and to promote their fusion, it is necessary that the pieces of rock or stone should be reduced to small fragments by stamping them. For those ores which occur in a sandy form, this is unnecessary; and in regard to rich silver ore, which contains very little or no lead and other metals, this process might be hurtful; for with dry stamping a great deal would fly off in dust, and with wet stamping a considerable part would be washed away by the water. However imperfect the knowledge of the ancients may have been in regard to the fusion of ores, they were acquainted with the benefit of stamping; but the means they employed for that purpose were the most inconvenient and expensive. They reduced the ore to coarse powder, by pounding it in mortars, and then ground it in hand-mills, like those used for corn, till it acquired such a degree of fineness that it could be easily washed. This is proved by the scanty information which we find in Diodorus Siculus[832] and Agatharcides[833], in regard to the gold mines of the Egyptians; in Hippocrates, respecting the smelting-works of the Greeks[834], and in Pliny in regard to the metallurgy of the Romans[835]. Remains of such mortars and mills as were used by the ancients have been found in places where they carried on metallurgic operations; for instance, in Transylvania and the Pyrenees. The hand-mills had a resemblance to our mustard-mills[836]; and for washing the mud they employed a sieve, but in washing auriferous sand they made use of a raw hide. From the latter, Count von Veltheim has explained, in a very ingenious manner, the fable of the ancients concerning the ants which dug up gold[837]. Our works for pounding ore, at present, are stamping-mills, which consist of heavy stampers shod with iron. These stampers are put in motion by a cylinder furnished with cogs, which is driven by a water-wheel, and pound the ore in troughs lined with iron. When the ore subjected to this operation is poor, water is introduced into the troughs, which running through grates in the bottoms of them, carries with it the pounded matter into a gutter, where it becomes purified, and deposits the mud mixed with sand. One might conjecture that this apparatus was invented soon after the invention of cylinders with cogs; but this was not the case, though I am not able to determine the antiquity of these cylinders. At any rate, it is certain that mortars and sieves were used in Germany throughout the whole of the fifteenth century; and in France, to which the art of mining was conveyed in general from that country at a late period, they were still employed about the year 1579[838]. In the oldest times men were not acquainted with the art of employing water at mines in so advantageous a manner as at present. The bellows were worked by men; and those aqueducts raised on posts, by which distant water may be made to act on machines, was not yet invented. On this account, remains of ore are found in places where the moderns, in consequence of that indispensable article water, would not be able to maintain metallurgic works[839]. According to the researches which I have hitherto had an opportunity to make, our stamping-mills were invented about the beginning of the sixteenth century, and, as appears, in Germany; but I cannot determine with certainty either the name of the inventor or his country. Those who established or introduced the first stamping-works in Saxony and the Harz are only mentioned; and these, as usual, have been considered as the inventors. In the year 1519 the processes of sifting and wet-stamping were established in Joachimsthal by Paul Grommestetter, a native of Schwarz, named on that account the Schwarzer, whom Melzer praises as an ingenious and active washer; and we are told that he had before introduced the same improvements at Schneeberg. Soon after, that is in 1521, a large stamping-work was erected at Joachimsthal, and the process of washing was begun. A considerable saving was thus made, as a great many metallic particles were before left in the washed sand, which was either thrown away or used as mortar for building. In the year 1525 Hans Pörtner employed at Schlackenwalde the wet method of stamping, whereas before that period the ore there was ground. In the Harz this invention was introduced at Wildenmann by Peter Philip, who was assay-master there, soon after the works at the Upper Harz were resumed by Duke Henry the younger about the year 1524. This we learn from the papers of Herdan Hacke or Hæcke, who was preacher at Wildenmann in 1572. As far as can be concluded from his imperfect information, the first stamping-work there consisted only of a stamper raised by means of two levers fixed to the axis of a wheel. The pounded ore was then thrown into a sieve, called in German the _sachs_[840], and freed from the coarser parts. But as this stamping was performed in the dry manner, it produced so much dust that the labourers were impeded by it, and the ore on that account could not be properly smelted. The business however was not given up; new improvements were made, and soon after Simon Krug and Nicholas Klerer introduced the wet method, and fortunately brought it to perfection[841]. It is said in several modern works that wet stamping was invented in 1505, by a Saxon nobleman named von Maltitz. This assertion has been so often repeated, that it was known to Gobet[842], who adopted it as truth. I have not however been able to find the historian on whose testimony it is founded; but it appears by Gauhen’s Dictionary of Nobility that Sigismund Maltitz was chief surveyor of forests at the Erzgebürge, to the electorate of Saxony in the sixteenth century. FOOTNOTES [831] I shall refer those desirous of being acquainted with the nature of this labour, to Gatterer’s Anleitung den Harz zu bereisen. Göttingen, 1785, 8vo. i. p. 101. [Figures of the stamping-works may be seen in Ure’s Dictionary of Arts and Manufactures, pp. 818 and 1119.] [832] Diodor. iii. 13, p. 182. [833] Photii Bibl. p. 1342. [834] Hippocrates de Victus Rat. lib. i. sect. 4. [835] Plin. xxxiii. 4, sect. 21. [836] Gensane Traité de la Fonte des Mines. Par. 1770, i. p. 14. [837] Von d. goldgrabenden Ameisen u. Greiffen der Alten. Helmst.