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Thus when we pour nitrous acid on fulphur, and distil over a gentle fire, the nitrous acid is partly decompofed as well as the fulphur; and vitriolic acid is obtain ed. Now, it is faid, the pure air of the nitrous acid combining with the fulphur, changes it into vitriolic acid, while the other principle of the nitrous acid, the nitrous air, is difengaged, &c.
That we may enable our readers' to judge for themselves with regard to this grand procefs, we fhall here detail the arguments which the advocates for phlogifton oppofe to their adverfaries.
1. The combination of pure air in the combuftion of metals, of fulphur, of phofphorus, &c. does not exclude an inflammable principle in thefe bodies; for in the new theory, there is an inflammable principle or Inflammable air in the oils, fpirit of swine,&c. Now the combuftior of thefe fubftances is equally accompanied by the abforption of pure air. It is likewife admitted that there is a matiere charbonneufe in the lungs of animals, which combining with pare air in the act of refpiration, produces fixed air, &c. There is therefore no difficulty on this first question; it is only neceffary to know what becomes of the pure air in the different experiments in which it is abLorbed. In the combuftion of oil, it is faid that its inflammable air, and pure air are changed into water, which fuppofes that water is compofed of these two airs. In refpiration, the fame pure air, combining with the matiere charbonneufe forms fixed air. This fame pure air may therefore undergo fimilar or analogous combinations in the combuftion of fulphur, metals, &c.
2. The doctrine of the compofition, and decompofition of water is not attended with proofs fufficient to make us admit it. Accordingly very few of the learned have admitted
it. In truth, the combuftion of the two airs, the inflammable and the pure, never produce of water a quan tity equal in weight to themselves; neither is that water ever pure.
M. Cavendish always obtained in that experiment a fmall portion of nitrous acid. Dr Priestley fhewed me feveral ounces of water obtained from the combustion of the two airs in copper tubes. It was blue, and upon adding the vegetable alkali, the copper was precipitated, and a true nitre was obtained by cryftallizing it. M. Cavendish attributes this acid to a portion of phlogifticated air; but it would rather feem owing to inflammable air, which I confider as one of the principles of this acid.
Laftly, there remains a confiderable portion of impure or phlogisticated air.
We fee then that the compofition of water is far from being proved. The following is the explanation which I think may be given of the facts, without fuppofing that water is compofed of pure air and inflammable air.
When thefe airs are ignited they quit the matter of heat, which kept them in an aeriform ftate, and are disfipated through the veffels. Confequently they cannot any longer hold in folution the great quantity of water they contain, which is immediately precipitated.
This water refumes its original weight, a part of which was destroyed by the action of the matter of heat.
The pure and inflammable airs being thus defpoiled of their heat which reduced them to an aeriform state, and of the water which they held in folution, are reftored to their primitive ftate, they become concrete, and their molecules are then fufficiently minute to pass through the veffels and escape in part. A fecond portion forms the acids obtained; and, lastly, perhaps in the combustion, may not a third part preferve an aeriform ftate in order to conftitute that impure air which is always found, or may not this air be contained
contained in the pure and inflammable airs? But I would rather incline to the first opinion, because in the combination of the pure air with the nitrous, there is equally a production of impure air: laftly, I believe at prefent that a part of this phlogisticated air proceeds from a portion of the nitrous acid produced, which is decompofed in the combuftion of the airs.
It may be faid, that I affume without proof the paffage through the veffels of the air no longer in a state of vapour. But experiments with regard to the confiderable abforption of different kinds of air by water in clofe veffeis, demonftrate that these airs actually efcape through the veffels.
The proofs brought to establish the decompofition of water are not more conclufive. Iron, zinc, charcoal, expofed, it is faid, to the vapour of water in veffels of a red heat, are burnt, calcined, and give out a deal of inflammable air.
But thefe experiments are not unanswerable. We know, in the first place, that many bodies are not difengaged from their combinations without the intervention of another body. Thus effential oils cannot be made to receive the heat of boiling water except by means of the fpiritus rector. The fixed air of many fubflances is not difengaged entirely, except by the intervention of water. It is therefore very probably the fame with the inflammable air of metals, charcoal, &c. z. Many metals lofe a part of their properties on being combined with other fubftances befides pure air; thus iron may be combined with fulphur, arfenic, phofphorus, &c and form fulphureous, arfenical and phofphoric pyrites, which are combinations very different from thofe made by iron with pure air. Now, iron expofed to the vapour of water in veffels of a white heat, is abfo Jutely different from iron burnt in pure air. This laft is black, very duftile, &c. The other is much lefs ductile, is brittle, has acquired an increase of
bulk, has a cryftallized appearance, &c. Thus every thing tends to prove that the action of water on iron is very different from that of pure air.
Laftly, even though the compofition and decompofition of water were established, all these phenomena would not be explained.
When metals are diffolved in concentrated vitriolic acid, the fulphureous acid and fulphur are produced, but little or no inflammable air. If, on the contrary, the acid has been reduced by water, there arifes a good deal of inflammable air, which it is faid proceeds from the decompofition of the water. But this hypothefis cannot be maintained. I have fhewn that in this laft cale, the acid was decompofed as in the firft. Having put into two vesselsequal parts of weak vitriolic acid, I. threw into one of them a portion of feel filings. When the folution was completed, I took equal parts of alkali, and faturated the two acids. That in which the iton was diffolved was faturated with half of what was neceflary to faturate the other. A portion then of that acid muft have been decompofed. Now, what in this cafe could decompofe the water? I have proved, that pure water well-boiled does not act in a very fenfible manner on iron.
Pure air and inflammable air do no form water except in combustion. However we are obliged to fuppofe, in order to explain many phenomena, that their fimple mixture produces water: for inftance, when we mix volatile or ammoniacal alkali with the marine dephlogifticated acid, &c. This fuppofition, therefore, does not reft on futficient grounds.
We may then conclude from thefe, and many other facts, that it is not proved that water is composed of pure air and inflammable air, nor that it can be decompofed in these two airs : and that even if it were proved it would not afford an explanation to all the phenomena.
3. The third basis of the new theory is the specific heat of pure air, as it is affigned by Crawford, which in this fyftem is the only caufe of combuftion. This phenomenon is at prefent one of the greatest queftions among chemifts, and we may affirm, that on its folution depends that of all the problems with which they are engaged. But it does not appear to me that it can be explained by the mere difengagement of Specific heat from pure air combined. If the fpecific heat which pure air contains in its aeriform ftate were cápable of producing flame and light, we would then have flame and light as often as that air is combined, and ceafes to be in an aeriform flate. But this is not the cafe; for in the mixtare of pure air with nitrous air the abforption is almost as quick as in the combuftion of the fame pure air with inflammable air. Now, in the first experiment, there is only a fmall degree of heat without flame or light; and in the second, we have flame, light, and a confiderable degree of heat: whence I conclude that the flame and light proceed rather from the inflammable than from the pure air, without however denying that the heat of the pure air may contribute fomewhat.
It has been objected to me, that in the combination of pure with nitrous air, the matter of heat is immediately re-combined in the acid which is formed. It is for that very reason that there is neither light nor flame; and, the proof that this acid contains a deal of heat, is deduced from its a&ion on oils, metals, &c. but the other acids, fuch as the vitriolic, mixed with the fame fubftances, produce an equal heat; and yet in the combuftion of fulphur there is both heat and light. The answer is therefore infufficient.
All the explanation which the new theory gives of combuftion is founded on Crawford's experiments, who found fo much heat in pure air. But I fhewed, long ago, that the great levity of inflammable air proved that it contain ed a much greater quantity of the mat
ter of fire or of light, than any other kind of air. To this Crawford affents in the daft edition of his work. He fuppofes the heat of pure air to be 4.7490, and that of inflammable air to be 21,4000 that of water being 1,cooo. I confefs, that having often attempted to repeat Crawford's experiments with very fenfible thermometers, I never had any refuits that gave me fatisfaction. Therefore, without denying his experiments, I keep by my firft obfervations.
I cannot admit then what has been faid, " that though it were proved that "all combuftible bodics contain in"flammable ait, they would not al-,
ways burn except by the matter of "heat contained in the pare air. For if inflammable air contains more light and more heat than pure air; the light which it produces in combustion will come chiefly from itfelf; and if the light and flame of the combustion of inflammable air are owing to this air, it is very probable that it is the fame with all other combustible bodies, and that they all contain inflammable air.
I do not know, however, if all these ideas entertained of the specific heat of bodies with regard to combuftion, are well-founded; for fluids reduced to an aeriform state by the greateft degree of heat do not give out flame on condenfing. Water, for example, paffing through tubes of a white heat, or poured on bodies of the fame heat, and inftantly condenfed by patling through other tubes plunged in cold water, never yields light or flame, though it produces a great degree of heat. Yet when thus heated and reduced to an aeriform ftate, it fhould contain much more heat tl, pure air does. It therefore can by no means be the fpecific heat of pure air which yields the flame when it ceafes to retain its aeriform ftate. In fine, pure air in a concrete flate, combined with combustible bodies, produces alfo a bright inflammation as in it the detonation of ammoniacal nitre, of the calx of gold, fulminating filver, &c.
Extract from The Life of Thomas Chatterton, with Criticisms on his Genius and Writings. By G. Gregory, D. D. &c. 8vo.
ROM this narrative we learn, that Chatterton was born at Bristol in November 1752, about three months after his father's death, who had been master of a free school, and a finging man in Bristol Cathedral: That his mother taught him to read from an old black letter Teftament, or Bible: That in 1760 he was admitted into a charity fchool, where he was not diftinguished by any extraordinary improvement, tho' noticed for an influence over his play-mates, and his fondness for play, At the age of ten he began to take pleasure in reading; had recourse to a circulating library, difcovered traits of genius before he was twelve, and made a bit of feventy books he had read, chiefly of history and divinity. About this time he began to compofe, as appears by a fatire written in 1764, intitled Apeftate Will. Sometime afterwards, at an accidental meeting in the street with a gentleman, he mentioned his being poffeffed of certain old MSS. which had been found depofited in a cheft in Redcliffe church. On leaving school, he was bound apprentice to Mr Lambert an attorney of Bristol, in whofe office be was employed from eight o'clock in the morning till eight in the evening; and he was never abfent from his master's houfe after the hour limited, except once, when he had leave to fpend the evening with his mother and fome friends. In this fituation, but difliking the profeffion, he had been above a year, when, on the finishing of the new bridge in 1768, he inferted in the Bristol Journal, an account faid to have been taken from a very ancient MS. on opening the old bridge, and this was his firft publication. On being queftioned about VOL. X. No. 57.
this, he faid, it was one of thofe that had been found in Redcliffe church. Afterwards he produced the Briftow Tragedy, and frequently talked of the Poems of Rowley. He now employed all his leisure hours in reading, but his ftudies were defultory; one day he applied to heraldry and antiquities; another to metaphyfics and mathematics; and the next to mufic, aftronomy, and medicine. He tranfcribed Speght's Gloffary to Chaucer. From before November 1768, he began to write for Magazines, and during 1769 his contributions were many and various, whilft extracts from Powley made fome of the number. At this time he attempted to obtain the patronage of Mr Walpole, by offering him accounts of painters who had flourithed at Bristol, and by tranfmitting fpecimens of his ancient poems, with an authentic account of himfelf. The poems, however, being pronounced fpurious by Mr Mafon and Mr Gray, a cool answer was retained, and Chatterton was baffled in his hopes. Mr Walpole afterwards regretted that he had not seen this extraordinary youth, and that he did not pay a more favourable attention to his correfpondence; but, to be neglected in life, and regretted, and admired when these passions can be no longer of fervice, has been the ufual fate of learning and genius.
What follows is in the Author's own words.]
THE reader has hitherto contemplated Chatterton in the pleafing light of an ingenious and virtuous youth. I reluctantly proceed to de velope the only circumftance which has involved his name and character in difgrace, and which certainly de-,
prived the world prematurely of his excellent abilities. When or how he was unfortunate enough to receive a tincture of infidelity, we are not informed. Early in the year 1769, it appears from a poem on Happiness, addreffed to Mr Catcott, that he had drank deeply of the poifoned fpring: And in the conclufion of a letter to the fame gentle man, after he left Bristol, he expreffes himself: "Heaven fend you the comforts of Chriftianity; I requeft them not, for I am no Chriftian." Infidelity, or fcepticifm at leaft, may be termed the difeafe of young, lively, and half-informed minds. There is fomething like difcovery in the rejection of truths to which they have been from infancy in trammels. A little learning, too, misleads the aderstanding, in an opinion of its own powers. When we have acquired the outlines of fcience, we are apt to fuppofe that every thing is within our comprehenfion. Much study and much information are required to discover the difficulties in which the fyftems of infidels are involved. There are profound, as well as popular arguments, in favour of revealed religion; but when the flippancy of Voltaire or Hume has taught young perfons to fuppofe that they have defeated the former, their understandings feldom recover fufficient vigour to purfue the latter with the ability and perfeverance of a Newton or a Bryant.
The evil effect of thefe principles upon the morals of youth, is often found to furvive the fpeculative impreffions which they have made on the intellect. Wretched is the person, who, in the ardour and impetuofity of youth, finds himself releafed from all the falutary reftraints of duty and religion; wretched is he, who, deprived of all the comforting hopes of another ftate, is reduced to feek for happiness in the vicious gratifications of this life; who, under
fuch delufions, acquires habits of profligacy or difcontent! The progrefs, however, from fpeculative to prac tical irreligion, is not fo rapid as is commonly fuppofed. The greatest advantage of a strict and orderly education is the resistance which virtuous habits, early acquired, oppofe to the allurements of vice. Thofe who have fullied the youth of Chatterton with the imputation of extraordinary vices or irregularities, and have afferted, that "his profligacy was, at least, as confpicuous as his abilities," have, I conceive, rather grounded thefe affertions on the apparently profane and immoral tendency of fome of his productions, than on perfonal knowledge, or a correct review of his conduct. During his refidence at Bristol, we have the most respectable evidence in favour of the regularity of his conduct, namely, that of his mafter, Mr Lambert. Of few young men in his fituation it can be faid, that, during a courfe of nearly three years, he feldom encroached upon the frict limits which were assigned him, with refpect to his hours of liberty; that his mafter could never accufe him of improper behaviour, and that he had the utmost reafon to be fatisfied he never fpent his hours of leifure in any but refpectable company.
But though it may not always be the effect of infidel principles, to plunge the perfon who becomes unfortunately infected with them into an immediate courfe of flagrant and fhameless depravity, they feldom fail to unhinge the mind, and render it the fport of fome paflion, unfriendly to our happiness and profperity. One of their firft effects in Chatterton was to render the idea of fuicide familiar, and to difpofe him to think lightly of the most facred depofit with which man is entrusted by his Creator. It has been fuppofed that his violent death in London, was the fudden or almost instant effect of ex