by the course of a river. The inclination of the ftrata, he tells us, is fometimes fo regular, that it may be employed to measure the height of the mountain with tolerable exactness.

The next memoir contains the obfervations on mines of coal inflamed by accident, by the imprudence of the miners, or heat raised by fpontaneous fermentation. The author defcribes feveral of thefe, which burn as long as any fuel remains.. When a brook has been conducted into the mine, to extinguish the fire, whofe heat is very fenfible on the furface, it occafions a little eruption, the nature of which we now very well understand, and hall explain in another part of this article.

Some Mifcellaneous obfervations follow. The first is on calces of iron, found in the fchiftus that lies over coal. They refemble precipitations of that metal by acids, and one, produced by M. Sage, was like the precipitate obtained by the faccharine. The fecond relates to the means of making fœtid bitumens aromatic: afphaltum, expofed to a ftrong fun, in a clofe veffel (we fuppofe of glafs), refembles in its odour benzoin. In the laft volume, M. Fougeroux defcribed fulphur found in the rakings near the gate Saint Antoine: the ground was that on which a flaughter-house formerly stood. M. Morand found the fame in the ruins of a houfe fituated near an old fewer.

The aventurine, in M. Sage's opinion, is a kind of quartz. It is chiefly made up of fmall grains of this ftone, and to it owes its peculiar property, which is found too in fome fpecies of feld-fpath. M. Daubenton thinks that the ftone, formerly called aventurine, was rather of the latter fpecies.

The Chemical part of this volume is very interefting, and we have often had occafion to hint at it; we must therefore rest on it with unusual care. In the first article, On Vegetable Analyfis,' count de Milli explains the method by which he intends to analyfe vegetable fubftances, and afterwards to extend it to the animal kingdom. There is a candour and generofity in his conduct in explaining the method, which fhews that he is more folicitous for the advantage of science than for the honour of discovery. He now only explains his apparatus, and may be followed by chemifts of different nations. We lately, in our review of Fourcroy's Lectures, mentioned how little we were really acquainted with animal fubftances; but we recom mended an attention to the fpontaneous changes, and an examination of the different parts, rather than to the more violent feparation by means of heat: we know that in this field a rich harvest of discovery may be reaped. The count's plan is not, however, very different. He employs a lamp furnace, by which he gives the fubftance to be examined a constant heat, from the temperature of the air to that of boiling water. The degree is known by the number of threads in the wick, which must be near, but not very exactly reach to the truth. In this apparatus the substances underwent the different fermentations;

a part

a part of each, in its different ftates, is diftilled by a given heat; and the products of this heat are feparated by properly ftopping the diftillation. This method has obviously many advantages, and it is faid to be even fuperior to M. Turgot's, by which the volatile principles are feparated without any, or, at moft, very little alteration of the remainder.

The memoir, which follows in the historical part, for it must be understood that the order of the memoirs themfelves differs, is that of Meffrs. Lavoifier and Meunier, on the Decompo fition of Water. In our Fifty-eighth Volume, pages 250 and 414, we gave a diftinct and copious account of the labours of Mr. Cavendish and Mr. Watt, who preceded M. Lavoisier in this difcovery. We must not now repeat it, but refer to thefe articles for what has been done in England. They open an extenfive profpect, beautifully adorned, and views that Newton never gueffed at. M. Lavoifier found that the' water arifing from the combuftion of pure and inflammable air was equal in weight to the airs employed: in this instance he was more fuccefsful than Mr. Cavendish; for in his experi ment four-fifths of the pure air remained. In many other trials fomething fimilar occurred: when, for inftance, filings of fteel, mixed with water, were put under a glafs, on a furface of mercury, a confiderable quantity of inflammable air was produced; the fteel was increased in weight, and the water diminished in quantity. We need not explain thefe appearances to chemifts, who will immediately fee reafon to fufpect that the inflammable air was produced from the water. We shall mention that water is produced in Dr. Prieftley's experiment of reviving calces of metals by inflammable air. All the fame effects, though lefs completely, we are informed follow the reduction of metals in vitriolic acid air.

It is obferved, that aeroftatic machines, and reflections on the means of fupplying them with inflammable air, firft fuggefted the principal experiment of thefe chemifts. We will now own our obligations to them. Water fell by drops from a funnel. on a gun barrel heated red-hot, and kept in that ftate by a conftant fire; the confequence was, a copious production of inflammable air. The infide of the gun was lined with a black glittering fubftance, not malleable, which, when reduced to powder, appeared a true martial æthiops. But this was not fufficient: M. Lavoifier wanted to know the weight of the water which was loft in the experiment, that of the inflammable air, and the increafe of weight in the gun barrel. The fum of thefe ought to be equal to the weight of the water employed. Befides, the external part of the barrel might have been calcined, and they could not be too exact. They then tried to extinguish red-hot metals in water, and to preferve the air; in this way they found inflammable air produced only by iron and zinc, the only metals which furnish it in folution with acids. A copper tube was therefore used instead of the iron

one,

one, and pieces of iron, weighed with the greatest exactnefs, put into it. When the experiment was tried with these variations, and allowance made for the water which efcaped, the weight of inflammable air, added to the increase of the weight of the iron, was exactly equal to that of the water originally added.

This theory, he obferves, explains many important phonomena. Vegetables, nourished with water, breathe vital air; the inflammable part of the water is preserved, and gives colour and inflammability to the plant. We may add, that fickly vegetables are yellow, and thefe are exprefsly found to produce phlogisticated air. In burning fpirit of wine, it is obferved, that we can collect a greater quantity of water than we lofe of fpirit; that is, if two ounces of spirit are burned, and half an ounce only remains, more than an ounce and half of watermay be collected. This water, our author thinks, arifes from the union of pure air, which ferves for the burning, united to the inflammable air of the fpirit. We may fuppofe then, that in the fpirituous fermentation of a folution of fugar in water, the vital air, one of the component parts of the water, uniting with the coaly matter (we should call it phlogistic) of the fugar, forms the fixed air, which iffues fo abundantly from the fermenting matter; while the inflammable air, with the fame principles, forms fpirit. In fact, we find that spirit of wine in burning, and confequently combining with pure air, produces fixed air; a proof that it contains the fame fubftance which in the fugar contributed to form the fame acid.'

We have given thefe experiments at fome length: though we think the conclufions highly probable, fomething is yet necef fary to be added. Some of the doubts, which might have arifen, are, we think, obviated by Mr. Watt and Mr. Ca. vendith's experiments; but fome remain. It is remarkable that this inflammable air appeared only when iron or zinc were employed; and as we procure this air from thefe metals in other experiments, it feems probable that it is rather furnished by the metals themselves than by the water. It may indeed be alleged that iron has greater attraction to vital air than any other metal, fince it extracts fome portion of this air from the atmo sphere; but we have no evidence of the fame power in zinc. If we reverse the language, we may allow that they have both a more powerful attraction for fixed air than any other perfect metal, and would confequently be more capable of decompofing water, if one of its component parts was fixed air; but, as in many inftances, the language rather than the facts differ, we may perhaps with fafety transfer the analogy. Manganefe has a more powerful attraction to fixed air than even iron; black lead probably fill more. We think that experiments with thefe fubЯances might contribute to elucidate the fabject.

The hiftorian of the Royal Academy obferves, that M. Lavoifier's theory is not generally adopted; yet he adds, that few

che

chemical theories are founded on more fimple or more conclufive experiments. Light and heat, he obferves, feem to be neglected in the operation, and these are either combined with water, or separated from the airs by combuftion; fo confequently we must either acknowlege that water is formed of these two fluids, minus the quantity of light and heat; or that each of thefe fluids is water joined with light and heat. But, as no experiments have been made on this fubject, he thinks the balance inclines towards M. Lavoifier.

As it is impoffible to finish this volume without extending our article too far, we fhall defer the remainder to a more convenient opportunity.

Memoires Hiftoriques, Politiques & Occonomiques, fur les Revolu tions Anglaifes dans l'Indoftan. Par J. A. Pallebot. Svo. Utrecht.

Ta time when we have fo many authors at home, who

aim at degrading the rank, and leffening the confequence of our country, it is with great pleasure we find ourselves confidered as important by foreigners. M. Paillebot affures, the public, that the English poffeffions in India are fufficient to change the politics of Europe, and earnestly invites all other nations to join together, and crufh the evil in the bud.' This author claims our attention on the subject of the affairs of India, from his long refidence in various parts of the country, and the knowlege which his rank and employments there muft neceffarily have procured. He profeffes to take things ab ovo,' but is not always original. In his account of the Bramins, he tranfcribes from Hollwell, whofe name he induftrioufly conceals, even in defcribing an event where he was a great fufferer, and mentioning a mausoleum which he built in confequence of it. The civil hiftory is taken from Orme, the Life of Nadir Shah, and other English authors: we can often difcover the particular paffages. In the narration of these events, with which the author may be fuppofed to be perfonally acquainted, he is very bitter against the English, and attributes much of our fuccefs to bribery; but if there be a crime in offering a bribe, there is furely a meanness in accepting it.

We

After making proper allowances for the envy with which he beholds the profperity of the English in India, and the manifeft partiality in favour of his own countrymen, these Historical Memoirs may be read with great pleasure, and contain many important obfervations.-But we must take notice of fome abfurdities in his account of a late noble general. fhall extract the paffage. Loaded with the fpoils of Afia, he returns to Europe, where, finding no farther fcope for his infernal Machiavelifm, his genius, recoiling on itself, foon becomes a prey to the avenging furies. His imagination, troubled by the reproaches of his confcience, fees nothing but

maf

maffacres, prifons, and spectres. Eager to fly from them, to fly from himself, he goes from England to France, runs from France to Italy, returns to England, where the fight of the tragedy of Montezuma, reprefented at Bath, completes his horror, and renders the light of the day horrible. In this af fecting profpect of the horrible cruelties committed in Ameaica by the Spaniards, who conquered it, he recognized his. actions and exploits in Afia. The imprecations of Montezuma on the stage seemed to ftrike him with curfes in his box. He ftarts from it in terror, haftens precipitately to London, orders his carriage for a journey to France, and almoft in the fame moment feizing a knife from his cabinet &c.'

Though we allow the force and pathos of this description, yet we must observe, that no tragedy of the name of Montezuma has been reprefented many years. That of Dryden has been long neglected. There was an opera of that name, but it could not be performed at Bath; and the artificial distress of an opera finger was never, we believe, fufficient to drive any man to defpair. If our author's information was not better on the affairs of India, much dependence cannot be placed on his ac

counts.

The following extract from his Profpectus is no improper fpecimen of his flyle and manner. Having allowed that the French were the firft who aimed at a territorial revenue; that this alarmed the English, and produced the conteft which, after the wars in 1755 and 1762, ended in the enormous em pire established by us on the ruins of the Mogul, he proceeds:

This formidable Coloffus, from the bofom of Afia, threatens Europe, which, by a ftrange fafcination, feems to look on the vast mass with indifference. Is the reftlefs genius, which used to prefide over the balance of Europe, enchanted ?-or does it reckon the weight of Afia, in the hands of England, as of no confequence? What! the contests for the poffeffion of a small province in Italy, Germany, or Flanders, have more than once raised a flame in Europe, which has trembled for its liberty, and cried out against the afpiring prince for his ambition to attain an univerfal monarchy and when England engroffes, one after another, the kingdoms of Afia, the nations of Europe, with a liftleffnefs unworthy of their dignity, leave their common rival to run his race, without an obftacle, when their ruin is the prize that it feeks, and which it is almoft ready to feize. Shall an age, diftinguished by revolutions fo important, pafs away without our perceiving thofe events, which will render it an object of attention to the eyes of pofterity?

Let us roufe, for it is time, and guard against the fur prizes which England prepares, under the veil which the fpreads, with anxious concern, over ufurpations already com pleted, and others yet in agitation. It is this deceitful veil which I mean to tear in pieces. After having employed twen ty-eight years in Afia, obferving and oppofing the defigns of VOL. LXI. Jan, 1786.