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, the substance to which it has the also water is incapable of uniting with :.. eatest affinity, in circumstances the any more phlogiston, as fulphur is,
oft favourable to the closest and most both being already faturated. timate union; for both, in the act Mr. Cavendish is inclined to think,
inflammation, are rarefied to the that pure inflammable air is not pure ghest degree; both give out their phlogiston, because it does not imme
ecific fire, the great obstacle to their diately unite with dephlogisticated air, lion, it being by the inflammation when both airs are simply mixed with onverted into sensible heat (a circum- each other; this reason feems to Mr. K.
Ince which, in Mr. K.'s opinion, confti- of no moment, because several other RT tes: the very essence of flame;) the substances, that have the strongest affi
sulting compound having then loft nity to each other, refuse to unite sude greatest part of its fpecific fire, is denly, or even at all, through the very
cessarily reduced, according to Dr. same cause that dephlogisticated and Su
ack's theory, into a denser state, infiammable airs refuse to unite; viz. hich the present experiment thews to on account of the specific fire which
water; whereas, in common cases they contain, and must lose, before
combustion, the phlogiston being such union can take place: thus, fixed nser and less divided, unites less in- air will never unite to dry lime, though nately with the dephlogisticated part they be kept ever so long together;
common air, consequently expels thus, if water be poured on the strong
s of its specific fire, and therefore eft oil of vitriol, they will remain fe***rms lefs denfe compounds, viz. fixed veral weeks in contact, without uniting, td phlogisticated airs; and so much as Mr. K. himself has experienced; and
more, as a great part entirely yet, in both cases, the specific fire need be capes combustion; but it seems pro- expelled only from one of the subble, that in very strong and bright Itances, and not from both: but after
lammations the union is more per- a long time they will unite; so also curt, and water formed.
will inflammable and dephlogisticated Water being then the result of the air, as Dr. Priestley has discovered sest and most intimate union of de- since his last publication. logisticated air and phlogiston, it That phlogisticated air should confit
very improbable that it is of fuperfaturated nitrous air Mr. K. er decomposed by the affinity of thinks improbable, as it retains its phloy
acid to phlogiston, as all the ex- giston much more strongly than nitrous riments hitherto made seem to prove air, which, according to the general laws at phlogiston has a stronger affinity of affinities, it Mould not, if it condephlogisticated air than to any other tained an excess of phlogiston; and, as oftance, except hot metallic calces; Dr. Priestley and Mr. Fontana repeatd these, in my opinion, are incapa- edly assure us, they have converted it ; of forming any union with water, into cominon air, by washing it in cept as far as they are faline, but water, in contact with the atmosphere. ay never can be reduced by it.
So Answer to Mr. Kirwan's Remarks upon the Experiments on Air. By enry Cavendish, Esq. F. R. S. and S. A. Read March 4, 1784. In this paper Mr. Cavendish pro- " Mr. De LASSONE found that Tes to take no notice of the argu- filings of zinc, digested in a caustic ents used by Mr. Kirwan in his re- fixed alkali, were partially diffolved arks, on which he leaves every read- with a small effervescence, and that the
to form his own judgement. He alkali was rendered in some measure nfines himself to such of the expe- mild. This mildness of the alkali Mr. nents mentioned there as may be Kirwan accounts for, by supposing that ought to disagree with his opinion. the inflammable air, which is feparated is observations upon these we shall during the solution, and, causes the ve in his own words :
effervescence, unites to the atmospheric LOND. Mag. Dec. 1784
air contiguous to it, and thereby ge- calcination, however, called rufting, nerates fixed air, which is absorbed by which is personned in the open air; the alkali. But, in reality, the only but this is so now an operation, that circumstance from which Mr. De Laf- the ruft may easily imbibe a fufficient sone judged the alkali to become mild, quantity of fixed air, notwithstanding was its making some effervescence when the small quantity of it usually confaturated with acids; and this effer- tained in the atmosphere. vescence is more likely to have pro- “ Mr. Kirwan allows that limeceeded from the expulsion of inflam- water is not rendered cloudy by the mable air than of fixed air, as it seems mixture of nitrous and common air; likely that the zinc might be more but contends that this does not prove completely deprived of its phlogiston that fixed air is not generated by the by the acid than by the alkali. union, as he thinks it may be absorb.
“ In the above-mentioned paper, I ed by the nitrous selenite produced by say, Dr. Priestley observed, that quickthe union of the nitrous acid with the filver, fouled by the addition of lead or lime. This induced me to try hom tin, deposits a powder by agitation and fmall a quantity of fixed air would be exposure to the air, which consists in a perceived in this experiment. I acgreat measure of the calx of the imper- cordingly repeated it in the same manfect metal. He found too fome pow- ner as described in my paper, excep, der of this kind to contain fixed air; that I purposely added a little fixed but it must be observed, that the pow- air to the common air, and found that der used in this experiment was not when this addition was th of the prepared on purpose, but was procured bulk, or oth of the weight of the from quicksilver fouled by having been common air, the effect on the lineused in various experiments, and may water was such as could not posibly therefore have contained other impu- have been overlooked in my experie rities besides the metallic calces. On ments. But as those who suppose fisthis Mr. Kirwan remarks, that Doctor ed air to be generated by the mixture Pricitley did not at firit prepare this of nitrous and common air may object powder on purpose, but he afterwards to this manner of trying the experi, did fo prepare it (4 PR. p. 148 and ment, and fay that the quantity of 1,49) and obtained a powder exactly of fixed air absorbed by the lime-wales the faine fort. It was natural to fup. was really more than th of the buk pose from this remark, that Dr. Priest- of the common air, being equal to that ley must have obtained fixed air from quantity over and above the air genethe powder prepared on purpose, and rated by the mixture, I made another that I had overlooked the panlage; but, experiment in a different manner on turning to the pages referred to, I namely, I filled a bottle with line
. was surprised to find that it was other- water, previoudy mixed with as mou wife, and that Dr. Priestley not so nitrous acid as is contained in an eru much as hints that he procured fixed bulk of nitrous air, and having air from the powder thus prepared. verted it into a vessel of the same, ki
“ With regard to the calcination of up into it, in the fame manner as a metals, it may be proper to remark, the above-mentioned experiments, . that this operation is ufually perform- mixture of common-air with the ed over the fire, by methods in which its bulk of fixed air, until it was hit they are exposed to the fumes of the full. The event was the same as b burning fuel, and which are fo replete fore; namely, the cloudiness produce. with fixed air, that it is not extraor- in the lime-water was such that I couli dinary that the metallic calx should, not poffibly have overlooked. It maut in a short time, absorb a confiderable be observed, that in this experimen: quantity of it; and in particular red no fixed air could be generated, and lead, which is the calx on which moft till greater proportion of the lineexperiments have been made, is always ter was turned into nitrous felenite to prepared. There is another kind of than in the above-mentioned experi
ments; fo that we may fafely conclude, Prieitley's, in which he obtained fixed that if any fixed air is generated by the air from a mixture of red precipitate mixture of common and nitrons air, and iron filings. This at first seems it must be less than th of the bulk really a strong argument in favour of of the common air.
the generation of fixed air; for though “ As for the nitrous selenite, it plumbago, which is known to conlist feems not to take the effect of the chiefly of that substance, has lately fixed air at all less sensible, as I found heen found to be contained in iron, by filling two bottles with common yet one would not have expected it to air mixed with tödth of its bulk of be decompounded by the red precipi. fixed air, and pouring into each of tate, especially when the quantity of them equal quantities of diluted lime- pure iron in the filings was much more water; one of these portions of lime- than sufficient to supply the precipitate water being previoully diluted with an with phlogiston. The following exequal quantity of distilled water, and periment, however, shews that it was the other with the same quantity of a really decompounded; and that the diluted solution of nitrous selenite, fixed air obtained was not generated, containing about 7dth of its weight but only separated by means of this of calcareous earth; when I could not decomposition. perceive that the latter portion of lime- “ Five hundred grains of red prewater was rendered at all less cloudy cipitate mixed with 1000 of iron than the former. Though the nitrous filings yielded, by the assistance of felenite, however, does not make the heat, 7800 grain measures of fixed air, cffect of the fixed air less sensible, yet besides 2400 of a mixture of dephlothe dilution of the lime-water, in con- gisticated and inflammable air, but sequence of some of the lime being ab- chiefly the latter. The same quantity forbed by the acid, does ; but, † be- of iron filings, taken from the same lieve, not in any remarkable degree. parcel, was then dissolved in diluted
“ There is an experiment mention- oil of vitriol, so as to leare only the ed by Mr. Kirwan, which, though it plumbago and other impurities. These cannot be considered as an arguinent mixed with 500 grains of the same red in favour of the generation of fixed air, precipitate, and treated as before, as he only supposes, without any proof yielded 9200 grain measures of fixed that fixed air is produced in it, does air, and 4200 of dephlogisticated air, yet deserve to be taken notice of as a of an indifferent quality, but without curious experiment. It is, that, if ni- any sensible mixture of inflammable trous and common air be mixed over air. It appears, therefore, that less dry quicksilver, the common air is not fixed air was produced when the red at all diminished, that is, the bulk of precipitate was mixed with the iron the mixture will be not less than that filings in substance, than when mixed of the common air employed, until only with the plumbago and other imwater is admitted, and the mixture purities; which shews that its proagitated for a few minutes. The rea- duction was not owing to the iron itson of this in all probability is, that felf, which seems to contain no fixed part of the phlogisticated nitrous acid, air, but to the plumbago, which coninto which the nitrous air is converted, tains a great deal. The reason, in all remains in the ftate of vapour until probability, why less fixed air was procondensed by the addition of water. duced in the firit cafe than the latter is, A proof that this is the real case, is, that in the former more of the plumthat in this manner of performing the bago escaped being decompounded by experiment, the red fumes produced the red precipitate than in the other. on mixing the airs femain visible for It must be observed, however, that the some hours, but immediately disappear filings used in this experiment were on the addition of water and agitation. mixed with about th of their weight
“ The most material experiment al- of brass, which was not discovered till ledged by Mr. Kirwan is one of Dr. they were dilluled in the acid, and
3 H 2
which makes the experiment less deci- generation of fixed air. As to the first sive than it would otherwise be. The method, or the calcination of metals, quantity of fixed air obtained is also there is not the least proof that any much greater than (according to Mr. fixed air is generated, though we cerBergman's experiment) could be yielded tainly have no direct proof of the conby the piumbago usually contained in trary; nor did I in my paper infinuate 1000 grains of iron; so that though that we had. The same thing may be the experiment seems to shew that the said of the burning of sulphur and fixed air was only produced by the de- phosphorus. As to the mixture of nicomposition of the impurities in the trous air, and the combustion of infilings, yet it certainly ought to be fammable air, it is proved, that if any repeated in a more accurate manner. fixed air is generated, it is so small 23
• Bsfore I conclude this paper, it to elude the nicest test we have. It may be proper to sum up the state of is certain too, that if it had been fo the argument on this subject. There much as oth of the bulk of the comare five methods of phlogiítication con- mon air employed, it would have been sidered by me in my paper on air; perceived in the first of these methods, namely, first, the calcination of me- and would have been senible in the tals, either by themselves or when second, though still less. So that, oot amalgamated with quicksilver; feconds of the five methods enumerated, it has ly, the burning of sulphur or phospho- been shewn, that in two no senfible rus; thirdly, the mixture of nitrous quantity is generated, and not the leaft air; fourthly, the explosion of infiam- proof has been alligned that any is a mable air; and, fifthly, the electric two of the others; and as to the late spark; and Mr. Kirwan has not point- good reasons have been assigned for ed out any other which he confiders thinking it inconclusive; and, there as unexceptionable. Now, the lait of fore, the conclusion drawn by me is these I by no means consider as unex- the above-mentioned paper seems fus. ceptionable, as it seems much moft ciently justified; namely, that though likely, that the phlogistication of the it is not impoffible that fixed air ray air in that experiment is owing to the be generated in some chemical proofburning or calcination of some fub- ses, yet it seems certain, that it is not fance contained in the apparatus *. It the general effect of phlogisticating air, is true, that I have no proof of it; but and that the diminution of com.ca there is so much probability in the opi- air hy phlogistication is by no means nion, that till it is proved to be erro- owing to the generation of separatica neous, no conclufion can be drawn of fixed air from it. from such experiments in favour of the
* In the experiment with the litmus I attribute the fixed air to the burning of the lines of decompositien, as Mr. Kiruan repreients ir, which is a fufficient reaion why no fixed and the found when the experiment is tricá with air in which bodies will not burn.
IRISH INTELLIGENCE, EXTRACT OF A LETTER FROM BELFAST, SEPT. 25. “STON after the difmifion of foc unanimously that the following addreia of collector of Lisburn, a numerous man and William 'Todd Jones, Efes meeting of the Constitution Club was representatives in Parliainent for te held in that town, when it was resolved town of Lisburn.
“ To WILLIAM SHARMAN, Esq. « SIR,
“ WE embrace with pleasure high respect we entertain for your cha. the opportunity which your presence racter, and of paying that debe of grathis day affords us of exprelîng the titudes to which your services in the cause of liberty and your country have has ever appeared; and it is now evijuftly entitled you. Unpolluted by the dent that an earnest desire to promote example of a venal and profligate so- the interest of Ireland is a crime neciety, uninfluenced by the displeasure ver to be forgiven by the present adof an arbitrary and undignified admi- ministration. Whilft it is well known nistration, you have preserved your that a contrary practice is the sure road integrity, and returned to us ftamped to honours and wealth. with the exalted character of an up- - The situation of that country is right senator and an honest man. Your deplorable indeed, when the enormity difinission from a lucrative employment, of its rulers becomes a mark of distincwhich you had filled for a séries of tion, and their friendihip the criteyears with honour to yourself and ad- rion of infamy. It is with the utmost vantage to the public, is alarming to satisfaction we reflect that an ample the last degree, and calls for the serious fortune has placed you out of the reach attention of every Irishman. If your of their malevolence, and we pray that exertions in the public cause had not you may long live an object of venebeen tempered with moderation and ration to your countrymen; and a wisdom; if, in place of the manly con- bright example of disinterested patriduct of the dignified patriot, you had otism to all who are delegated to conassumed the character of the dangerous fult for the good of the nation. incendiary, or factious demagogue,
(Signed by order) there would have been some pretence
« ROBERT BELL, Sec." to justify your disinillion. None such
" To WILLIAM TODD JONES, Efq. “SIR,
• WE embrace with alacrity which has so uniformly marked your the opportunity this day offers, of ex- conduct. We rejoice that the sanguine presing that affectionate attachment to expectations of your honest and spiyour person, and perfect confidence in rited constituents have been so amply your political integrity, which your fulfilled. We rejoice that by you and amiable deportment in private life, and your worthy colleagues this fact has manly, decided conduct in the House been completely establithed, that when of Commons have so justly entitled electors themselves are wife and honest you to. We, who were so deeply in- they will never be disappointed in the terested in your election, could not elected. view, without exuitation, the ability (Signed by order) you displayed in the cause of the pub
ROBERT BELL, Sec." lic, and that consistency of patriotism
To these Addresses the following Answers were fent next day: 5. To the GENTLEMEN of the CONSTITUTION CLUB. " GENTLEMEN,
“ TO a man of my principles, for the purpose of reformation, you no the first happiness of his life will be sooner resolved, than you succeeded; his being conscious to himself that he and you effected in the space of a few is an honest man. His next greatest months what your forefathers could comfort will be, to know that his not effect in a century. There is nofellow-citizens think him fo. The thing, gentlemen, wanting to the feelings of my mind afford me the fa- freedom of your country, but that your tisfaction of the first; and the good wishes may become as universal as your ness of your kind and affectionate address has put me in poffesfion of the “ With respect to the employment second.
which you allude to, I have been in “ I feel a pride in the approbation the poffeffion of it almost from my of fo respectable a body. Instituted infancy, during a period of twenty