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sword to support their meafures. Being warriors both by Inclination and habit, they fought in defence of their domains, took up arms to ufurp the poffeffions of others, and fometimes to refift their Sovereign. Hiftory prefents us with a thousand inftances of fuch conducts The violent and outrageous behaviour of the Laity was, no doubt, the original caufe of all this; but the enmity of the two orders alone is fufficient to fhew that there were frange abuses, and that these abuses were deeply rooted.

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When a numerous clafs of Citizens is exempted from common burdens and taxes, when it commands opinion, looks upon its privileges as of divine right, and when ignorance and fuperftition favour its views, it may undertake any thing, when it is once governed by interest and ambition. The authority of the Prelates, 'tis true, was, upon fome occafions, a restraint against crimes, and then it was of real utility; but as, according to the ufual courfe of human affairs, intérêt necessarily corrupted the exercife of this authority, it frequently became extremely dangerous.

The great number of monaftic inftitutions had likewise prodigious influence upon the lot and condition of the people. From time immemorial, the East had feen a great number of men devote themfelves to a folitary and contemplative life, to which they were easily excited by a warm climate, and a lively imagination. The Effenians among the Jews had fet the example to the Chriftians, who followed it with fo much the greater ardor, as their religion fet them more above earthly things. Egypt efpecially was peopled with Monks. In the fourth century, there were ten thousand of them, and twenty thousand Nuns, in the town of Oxyrynchus alone, where there were more monasteries than private houfes. And yet very few perfons are called by Providence to a ftate fo repugnant to the natural order of fociety, and which requires virtues fo fuperior to human strength. A relaxation of difcipline, and debauchery, therefore, could not tail of being introduced among the Monks. A valt multitude of them, vagabonds, fanatical and feditious, overwhelmed the Haft, diflurbed the peace of the Church, and fhook the Throne. The Emperor Valens, in the year 376, made a law that they should ferve in the armies, thinking it impoffible, by any other means, to reduce them to obedience. But fuch laws are feldom put in execution, and the remedy increases the disease.

The chriftianity of the Barbarians produced fcarcely any other effects than founding monafteries at a great expence, and enriching them by donations. The Monks had a confiderable portion of the lands, fome of which they cultivated, and this was at least an advantage to the countries which they inhabited. But as they became rich and numerous, they gradually loft fight of the fanctity of their inftitution; they were covetous, vain, ambitious, Warriors, Lords, &c. like the fecular Clergy; they contracted the vices of the age; debauchery and the most icancalous practices were found in the very fanctuary of religious aufterity.-The State, accordingly, loft a great many fubjects, and gained few good examples. People were dazzled at firft, with fair and promifing beginnings, and never looked forward to confequences, though the experience of the pait might have No poden a „ile did the sur taught

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taught them very useful leffons in regard to the future. But nations are governed by habit and prejudice!?

"We mult now, for the prefent, take our leave of this judicious and inftructive Writer, tho' we do it with regret. The fpecimen we have given is fufficient, we doubt not, to tempt our Readers to have recourse to the work itself, which will abundantly repay the pains of an attentive and repeated perufal. They will find Abbè Millot not only an elegant and wellinformed, but, with few, very few exceptions, indeed, a candid and impartial Hiftorian.

His hiftory is brought down to the treaty at Aix-la-Chapelle in 1748, and concludes with a fhort view of the principal revolutions which, in modern times, have happened in Afia.

ART. VII.

Hiftoire de l'Academie Royale des Sciences, &c.-The Hiftory of the Royal Academy of Sciences at Paris; together with the Mathematical and Physical Memoirs for the Year 1770. 4to. Paris, 1773

GENERAL PHYSICS.

MEMOIRS I. and II. On the Nature of Water, and on the Experiments that have been produced to prove the Poffibility of is Tranfmutation into Earth. By M. Lavoifier.

HESE Memoirs contain a very fingular folution of a

T problem that has long engaged the attention of Chemifts

and Philofophers; fome of whom have maintained the transmu-tability of water into earth, in confequence of certain Chemical and Botanical experiments, that feemed ftrongly to favour that affertion. We have lately pretty largely difcuffed this matter, in reviewing M. Le Roi's differtation on the fubject, in the Memoirs of this Academy for the year 1767; to our account of which we refer fuch of our Readers as are unacquainted with the ftate of the question, and the circumftances and reasonings relating to it. We fhall here only obferve that M. Le Roi maintained the immutability of water, and that we endeavoured to strengthen his opinion by fuch observations as occurred to us on the subject.

If the prefent Author's experiments, which indeed appear to have been made with fufficient accuracy, are to be depended upon, they fhew that the principal part of the earth, which has been collected from water after repeated diftillations in glass or other veffels, did not previously exift in that fluid; but that it proceeded from the retort itfelf, or the veffel in which the dif tillation was performed. This manner of accounting for the phenomenon is fo fingular and new, that we doubt, not but that our philofophical Readers will be gratified by our giving them the following abftract of the Author's experiments

See Appendix to our xlv. volume, 1771, page 515.

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To abridge the operation, and to avoid the inconveniences attending repeated diftillations, M. Lavoifier ufed the fimple expedient of cobǝbating the water, by means of a pelican; that is, a glafs alembic confifting of one piece, or fometimes of a body, with a head clofely luted to it, in which there is a small aperture, which after the introduction of the liquor is accurately clofed with a gafs ftopple. From this head proceed two curve fpouts, that enter into the belly of the alembic, and reconvey into it the vapours which fucceffively arife, and are condenfed during the diftillation; fo as to produce a continued circulation of the diftilling liquor, without interruption, or the neceffity of luting and unluting the vessels.

Into an inftrument of this kind perfectly clean and dry, which accurately weighed 1 pound, 10 ounces, 7 drachms, and 21 grains, he introduced fome pure rain water, which had previously undergone eight fucceffive diftillations. The pelicanwith its contents was found, by an accurate pair of scales that would turn with lefs than a grain, to weigh 5lb. 902. 4 dr. 41 gr; fo that the quantity of water contained in it was equal to 3 lb. 1402. 5 dr. 20gr. We omit the relation of some prepa ratory steps taken by the Author, to prevent accidents that might arise from the dilatation of the air, on the first heating of the vessel. The two laft mentioned weights were taken after the pelican and the water had been heated fufficiently to enable him fafely to close up the aperture in the head with a glass ftopple, which was immediately and accurately luted, fo as to prevent any poffible evaporation of the water.

A conftant and pretty equable heat, varying only between 60 or 70 degrees of a Reaumur's thermometer (in which the point of boiling water was marked at 85) was regularly kept up, by means of a fand bath heated by fix lamps, during the fpace of 101 days. The procefs was begun on the 24th of October.

Near a month paffed before the Author perceived any remark able appearance; fo that he began to defpair of the fuccefs of his experiment. On the 20th of December however, he per ceived fome minute particles moving through the water in va rious directions, which, on examining them with a magnifier, he found to be thin lamina or plates of a greyish coloured earth, of an irregular figure. On the following days, though they did not apparently increase in number, they grew evidently larger; fo that fome of them were by eftimation near two lines square, though they still continued prodigiously thin. During the whole courfe of the month of January, the number of theses lamina floating in the water fenfibly diminished. Having ac-: quired a greater fpecific gravity they fucceffively funk to the bottom of the cucurbit; while the remainder intirely lined the

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fides of the veffel, for as to give the water, which was feen through this thin earthy coating, a turbid appearance, though it was in reality tranfpanont.s

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At length, on the 1st of February, the Author perceiving that there was a confiderable quantity of earth collected, and fearing leaft fome unlucky accident fhould deprive him of the fruits of bis labour, thought proper to put an end to the procefs. He therefore extinguished his lamps, and as foon as his pelican was fufficiently cool, her carefully removed the luting that closed the aperture, and with no fmall degree of impatience" brought the pelican and its contents to the test of the balance.

On trial he found the whole to weigh 5lb. oz. 4 dr. 41 gr. 75 of, that is, of a grain more than at the commencement 7 of the process. This flight difference is of no confequence,-and ought to be attributed to a flight inaccuracy in the balance, or other circumitances; and it may fafely be concluded, în the” first place, that water neither acquires or lofes weight by a con-'7 tinued cohobation during the fpace of 10 days. It follows likewise, as there was no fenfible increase of weight, that the earth perceived in the pelican did not owe its existence to the matter of fire, or to any other extraneous fubftance, which might be fuppoled to have penetrated the glais. This earth therefore 1 muft either have been previously contained in, and now separated from, the water; or a part of the water must have been actually tranfmuted into earth; or the earth must have been fur- s nifhed by the glafs in which the operation was performed? In any of these cafes, either the pelican, or the water, muft have loft as much of its weight, as was equal to that of the earth produced in the operation.

For obvious reasons the Author did not endeavour to determine this question by weighing the water. It was fufficient to examine accurately the weight of the pelican. Having thered fore poured out into another glass all the water and earth contained in it, and made it perfectly dry, he found that it had loft no less than 7 grains andths of its weight. From hence he naturally concluded that the earth obtained in this process had actually been a part of the fubftance of the glafs veffel employed in it, abraded from its furface, or diffolved, by the water, He next examined the weight of the earth which had fubfided to the bottom of the water: but this, when per fectly dried, weighed only 4 grains and ths. Sufpecting however that the remainder of the fubftance which the pelican had evidently loft, was fill contained in the water, in a state of solution; he first inquired into the juftice of this fufpicion, by means of a very exact hydrometer, and found a weight of 15 grains neceffary to be added to that instrument, to make it fink as low in this cohobated. water, as it did in fome water of the Seine

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Seine that had been diftilled, and which was of the fame temper rature. Not content however with this trial, he distilled the water in a glafs alembic till it was reduced to a small quantity,1which he afterwards evaporated to dryhefs. By this process he obtained from it 15 grains and of the fame kind of earth with that abovementioned.

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The refults of these two proceffes gave him about 20 grains and of earth; that is, an excess of 3 grains above the lofs of weight fuftained by the pelican, which, the Reader will recollect, was equal to 17 grains and tw For this excefs the Author endeavours to account by attributing it to a fresh diffolu tion of the fubftance of the two veffels, which had been employed in the operations fubfequent to the cohobation. The caufe affigned however fcarce feems equal to the effect, when we confider that the water was only once poured into a glass veffel, and afterwards once diftilled in a glafs alembic. The prefence of this fuperabundant earth may in our opinion be more justly accounted for, by attributing it to the causes affigned in our Review of M. Le Roi's memoir above referred to. The Author has not yet had an opportunity to afcertain exacly the nature of this earth. From the few experiments he has yet made he was justly furprised to find that, though it was procured from glafs, it was not of the vitrefcible kind: at leaft it refifted degrees of heat more than fufficient to melt the hardest and most refractory glass. He propoles to repeat the experiment, and inquire further into the nature of this fubftance.

Having thus accounted, seemingly in a fatisfactory manner, for the appearance of the large quantities of earth obtained on the diftillation of water, and on which the opinion of the tranfmutability of this element into earth was principally founded; the Author next confiders the Botanical experiments by which this opinion has been further fupported.But we need not abridge his obfervations on this fubject, as we have formerly anticipated the arguments which he produces on this point, in our Review of M. Le Roi's Memoir above referred to * Vegetables, as we have there hinted, principally confift of water or phlegm, and, factitious air; and evidently derive a confiderable part of thefe and their other conftituent principles from the atmosphere. The air,' fays the ingenious Bonnet, is a fruitful foil, in which the leaves of vegetables collect a copious nourishment of every kind. Nature has given an extenfive furface to these aerial roots, in order that they may extract more abundantly from the air the various exhalations and vapours that are contained in it, &c.

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ས་མཇུག་ • See Appendix, vol. 45, page 5 18. de

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