coal, is feen in them, as in those of Halle, Tirol, and Saxony, but a great quantity of foffil fhells, principally bivalves and madrepores. The air is very pure in thefe immenfe fubterranean regions, which are faid to be three leagues in diameter, where broadest; the galleries are fo well cut out that the interior has always a communication with the exterior air, and none of those accidents happen in this mine which do great hurt in many others. One muft abfolutely fee thefe mines to be able to judge to what degree of perfection the Saxons have carried the art of mining. It has been affirmed that people live here together with their wives and children; but this is falfe; the miners work only four hours, and at the end of that time they depart; but they have no occafion for watches to tell them when they ought to quit their labour; they receive a certain quantity of grease or oil, with wick, fo well proportioned that they repair to the common rendezvous when they fee no more remaining than what is neceffary to enable them to find their way thither. I was told that the workmen had more than once loft themselves in these mines, and that they had perished before they were found. At prefent they are numbered when they defcend; and if it is obferved that any of them are miffing at the hour fixed for their being at the bottom of the rope on the first story, fome of the carpenters, to whom that business is affigned, are sent to search for them. These miners do not in general live long, and many of them die at an early age, of diseases in the breast, because they are obliged to remain long in a bent attitude, and are exhaufted by fevere labour, as the falt of this mine is as hard as free-ftone. The internal labour of these mines is in part executed by horfes, let down into them never to be drawn up until they are no longer in a condition to work. Their ftables, ftalls, and troughs are cut out in the folid falt. In these ftables there are great numbers of rats, eight or ten of which I faw eating oats in the troughs with the horses: they were fo familiar that they did not feem in the leaft deranged on our appearance. It is generally allowed that all the horses which labour in these mines foon lofe their fight; and I examined one of them that had become entirely blind. Twenty-four are generally employed here, each of which draws a small fledge, made for tranfporting the falt from one place to another. It is to be obferved that, befides the beautiful staircase which conducts from the first ftory, there are also several ramps cut out in the mine, and deftined for the following purpofe: when the miners have dug out a certain quantity of falt in the lower ftories, it is formed into cylinders, the fragments of which are put into casks; these caíks 5 casks are then placed upon fledges, which are drawn by the horfes up the ramps already mentioned to the first story, where the general magazine is fituated. When this magazine is completely filled, the cafks are taken away by means of a rope fixed to a wheel, which is turned by a horfe at an opening formed for that purpose. C Befides feveral openings of this kind, which are destined for a particular use, there are in feveral places common ladders, placed in an inclining direction, which have a communication with each other, from the top of the mine to the loweft gallery. Thefe ladders enable the miners to defcend and go up, because if they went up by the rope they would waste a greal deal more time. I was affured in the year 1785 that the number of workmen employed in this mine did not exceed eight hundred; but Mr. Bernard relates that when he was there they amounted from twelve hundred to two thoufand. The quantity of falt dug out and exported has perhaps become lefs confiderable fince the difcovery of feveral falt mines in Germany; but this will always have the preference over others on account of the facility of working it, the goodness of the falt, and the inexhaustible fupply which there is of that fubftance. Though the arches of these galleries are very bold, no danger is to be apprehended from them, because they are lined with large beams, a foot fquare, which are kept together with strong pegs. The quantity of wood employed to fupport thefe galleries is immenfe, and it remains there perfectly found for many centuries; all the other pillars, whether of brick, cement, or falt, foon decay and are destroyed. The manner in which this mine is daily wrought is very ingenious. The mafter-miner first marks out the dimenfions which he requires in the pieces of falt to be cut from the folid mafs. Each block is generally eight feet in length, four in breadth, and two in thickness. After he has marked out a certain number, the workmen begin by making upon one fide fe veral holes, inclining a little downwards, three inches deep, and at the diftance of fix inches from each other. They then make a lateral groove from top to bottom, half an inch in depth, and putting large iron wedges into each hole, they ftrike them alternately with hammers, following their inclination. As thefe wedges fink into the falt an aftonishing echo is heard throughout the whole mine. When the block is ready to detach itself a latteral fiffure is formed in the upper part, and another in the direction of the holes; the workman then takes a piece of wood, two or three inches fquare, introduces one end of it into the fiffure made by the wedges, and preffing upon it as on a lever, a crafhing crashing noise is heard, which announces the fall of the block; when it falls upon a fmooth place it remains entire, otherwise it breaks into five or fix pieces. The miners think they give a grand treat to strangers who vifit thefe mines when they detach whole blocks in their prefence. Each of them cuts out four regularly every day. These blocks are afterwards divided into three or four pieces, which are cut into the form of barrels or cylinders, in order to render them eafier of tranfportation." The third memoir of this work contains an account of the gold mine, or rather mine of auriferous iron, at Berefof in Siberia. The gold is found in the cells of a fpecies of quartz, but it adheres fo flightly that it may be easily fhaken out when the quartz is broken to pieces. This is the richest gold mine in that country, as far as relates to purity and weight. From the third of an ounce to an ounce of gold duft may be obtained from a quintal of the mineral. The fourth memoir contains an account of the mine of red lead in Siberia; and the fifth a chemical analysis of this subftance. The fixth memoir relates to the copper mines of Siberia; the seventh to the iron mines of that country; and the eighth to the tranfparent calx of lead found at Nerchinfky. In the last memoir the author has given a very curious topographical defcription of the city and environs of Moscow, with obfervations on the air, the productions of the foil, and the manners and customs of the inhabitants, which will be read with pleasure by medical gentlemen, as M. Macquart feems to have paid particular attention to the diseases which prevail in that climate during the different feafons. ART. XII. Biographical Sketch of the Life and Writings of M. de Romè de l'Ifle. M.De Romè de l'Ifle, diftinguished by his knowledge in chemistry and natural hiftory, was born at Gray in FrancheComte, in the year 1736. Scarcely had he finifhed his ftudies in the university of Paris when he was fent to India in 1757, as fecretary to a detachment of engineers; and, after being a victim, like many others of his countrymen, to the treachery of Lally, he was taken prisoner at Pondicherry, and conducted by the English to Tranquebar and China; but at length in 1764 he was permitted to return to Europe. Though M. de Romè de l'Ifle was then only twenty-nine years of age he had an ardent defire for ftudying natural history; and having been fortunate enough to form an acquaintance with Mr. Mr. Sage, at present profeffor of mineralogy in the school of mines, who had then begun his chemical career with fuccefs, that gentleman admitted him as a partner in all his scientific labours, affifted him with his purfe, procured him every opportunity of acquiring fuch knowledge as might be useful to his views; and in fhort rendered him all the fervices which friendfhip requires, and which it alone knows how to appreciate. The chemical lectures, which before this period had been read at Paris, were directed principally towards the improvement of phyfic and pharmacy; but Mr. Sage, in imitation of the Swedes and Germans, was determined to direct his towards the improvement of mineralogy. For this purpose he began to ⚫ form a valuable collection of ftones, foffils, and minerals; and it was by ftudying these objects that M. de l'Isle first acquired a tafte for that science. It was not, however, in mineralogy that he made his first appearance before the public. Tremblay, Réamur, Juffieu, and others, had given an account of fresh-water polypes, and their fingular manner of exifting; but they had not explained all the phenomena which they exhibited. By long reflection M. de I'Ifle was induced to believe that each polype might be confidered as a bag which formed a retreat for an infinite number of fmall animals, all diftinct from one another, but ftill concurring to the fame end. The work containing his obfervations on this fubject is entitled A Letter from M. Romè de l'Ile to M. Bertrand on fresh-water Polypes. It was published in 1766, and is now become exceedingly fcarce. About this time Mr. Davila, who poffeffed the most extenfive collection of natural history in Paris, wishing to dispose of it, chofe M. de l'Ile to write a defcriptive catalogue of what it contained. The latter, affifted by Mr. Sage, inftead of a fimple catalogue formed three large volumes in octavo, which gained him great applaufe, particularly from naturalifts. This circumftance gave M. de l'Ifle an opportunity of becoming acquainted with M. d'Ennery, a zealous collector of medals, and a warm protector of all those who had a tafte for the arts and the fciences. Though their ftudies were directed towards different objects, an intimacy commenced between them; and M. d'Ennery having proposed to M. de l'Ifle to lodge at his house, the latter readily accepted his offer. While M. de l'Ifle refided with M. d'Ennery, perfectly at his ease, and freed from the embarraffing cares of life, he continued his researches in mineralogy during the years 1769 and 1770, and in the year following publifhed the refult of them under the modeft title of An Effay on Chryftallography; or, A Defcription of the geometrical Figures peculiar to different Bodies of the mineral King dom, dom, commonly known under the Name of Chryftals. This work, however imperfect it may appear when compared with what the author did afterwards, was much fuperior to that of Linnæus. The latter had described about forty species of chrystals, but M. de l'Ifle gave an account of an hundred and ten, which he afterwards increased to four hundred. This effay first raised M. de l'Ifle's reputation; when it appeared the greater part of the mineralogifts of Europe thought it their duty to correfpond with a man who announced fuch extensive views; and he received a letter from the Pliny of the North, dated Upfal, May the 19th, 1773, in which that learned naturalift fays, Inter opera hoc feculo elaborata mineralogica certe chriftallographia tua primaria eft. Teftatur acerrimum tuum ingenium, obfervationum numerum immenfum, lectionem ftupendam, et tamen, quod rarum eft, animum in me mitiffimum.' In the year 1775 M. de l'Ifle was admitted a member of the academies of Mayence and Stockholm; and in 1780 the fame honour was conferred upon him by that of Berlin. These celebrated focieties, which, without waiting for folicitations, fearch out merit wherever it may be concealed, thought M. de l'Ifle's works fufficient to entitle him to this diftinction; but he found the cafe very different in France, where, as well as in England, intereft rather than talents conducts to literary honours. At the request of his friends M. de l'Ifle offered himself a candidate for becoming a member of the Academy of Sciences; and with this view he prefented his effay on Chryftallography, and read his excellent memoir On the Changes which take place in different metallic Mines, and particularly in martial Pyrites; but the grand and new ideas contained in these two works were not perceived, and one of the greatest geniuffes of France was thought unworthy of a feat at the Louvre. M. de l'Ile, however, who had taken this ftep contrary to his own inclination, merely that he might gratify the defire of his friends, was not at all affected by his disappointment, for he was confcious that the merit of his labours was so great that it would never hurt his reputation. The whole difgrace of it, indeed, fell upon the academy, and fome of its members, who, to favour a person whom they protected, called M. de l'Ifle a catalogue maker. This title may indeed be given him with great propriety, for he made eight catalogues in the course of his life, viz. that of Davila in 1767; Forfter's firft in 1769; that of Boucher in 1770; Forfter's fecond in 1772; that of Beoft in 1774; that of Gouffier and Pigache in 1776; Forfter's third in 1777; and Forfter's fourth in 1782. But a perfon must be very ignorant who cannot diftinguish the labours of a man of letters, who is defirous |