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THE
Edinburgh Magazine,

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LITERÀRY MISCELLANY,

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FOR SEPTEMBER, 1789.

With a view of Ellióck, the Seat of Lord Elliock *

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* In the County of Dumfries, near Drumlanrig. In this house was born the Ado
mirable Chricbton, whole Father, Chrichton of Elliock, was Lord Advocate of Scote
Land in the reign of James VI.

Siate of the L'AROMETER in inches and decimals, and of Farenheit's THER

MOMETER in the open air, taken in the morning before sunce, and at noon; and the quantity of rain-water fallen, in inches and decimals, from the 3 11t of August, 1789, to the 29th of Sept. near the foot of Arthur's Seat.

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.' Weather.

August 31

Sept:

10

11

Thermomi Barom. Rain. M. N.

29.625 29:57 29:325

0.43 29.25 0.04 29.4. 0.04 29.5825 0.02 29.63; 29.525

0.05 29.412 0.06 29.175 0.11 29.575 0.02 29.7625 1 0.05 29.9 125 0.02 29.574 0.02 29.175 0.01 29.475 29.65 0.04 29.5 29.3125 i 0.02 29.11 25 0.5 29.5125 29.72 29.6 29.875 29.825 0.1 29.775 0.05 29.325 29.42 0.18

29.15 h 5059 29.1

Quantity of Rain, 2.04

Clear. Cloudy, Rain. Ditto. Ditto. Small showers. Clear. Rain. Ditto. Cloudy. Ditto. Rain. Clear, small showers Cloudy, sm. showers. Clear. Dicro. Small thowers. Clear. Small showers. Rain. Ditto. Clear. Cloudy, fm. showers. Clear. Rain. Ditto. Clear. Rain. Rain. Clear.

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Present State of the Dispute between these Chemists who fupport, and those who

deny, the Doctrinae ; Phlubilion *.

TT was long known that metals ac- qual to 60 cubic inches, and absorI quired additional wcight by cal. bed 28 cubic inches of air. When cination ; that air was necessary to 2 grains of phosphorus were weigho' the operation, that it was absorbed, ed, fome hours after it was burnt, it and that when the metals were revi- bad increased a grain in weight." ved, they gave it out again. Ray, “ Large matches made of linen Boyle, Hales &c. had observed this. rags, were dipped in melted brim

" That the fulphureous and aeri- stone. The quantity of air which al particles of the fire, fays Hales, was abforbed by the burning match, are lodged in many of those bodies was 198 cc.bic inches, equal to roth which it acts upon, and thereby con- part of the whole air in the vessel.” liderably augments their weight, is “I made the same experiment in very evident in minium or red iead, a leser vellel, which contained but which is observed to increas: in 594 cubic inches of air, in which weight about t'ath part in undergo- 150 cubic inches were absorbed ; ing the action of fire; the acquired i. e. full th part of the whole air re!h: of the minium indicating the in the receiver.”' Exp. 103. Hales ali ion of plenty oft fulphur in therefore had the same results from the speration : for fulphur, as it is his experiments that we have ; for found that most vigorouily on light, we know that there is about of so it is apt to reflect the strongest, pure air in atmospheric air. viz. the red rays. And that there The same author found a lighted is good store of air added to the ini- candle under a receiver, absorb the rium, I found by distilling first 1922 air and then go out. He found that grains of lead, from whencel otain the remaining air was infected, and ed only 7 cubic inches of air; but could not maintain combustion. from 1422 grains, which was a cu- .“ The candlı, says he, cannot be bic inch of red lead, there arose in lighted again in this infected air by the like space of time 34 cubic in- a burning glass." Exp. 106. He ches of air." Veg. Stat. Cap. 6. had likewise observed, as well as on Exp. 119.

ther philosophers, that air was absorHales had also observed, 'that in bed in the process of refpiration. the combustion of sulphur, of phof- These experiments were known to phorus &c. there was an absorption all philosophers, and thus M. Lavoi. of air, a producrion of an acid, and fier explains himself with regard to an augmentation of weight. “ I'wo them in his Opufcules physiques et cny.. grains of phosphorus, says he, Exp. wiques. “ Hales thewed that air 54. easily melted at some distance “ contributed to the calcination of from the fire, flamed and filled the “ metals, and maintained that to it Tetort with white fumes, it absorbed " was owing the increased weight 3 cubic inches of air. A like quan. “ of metallic calces. He likewise tity of phosphorus fired in a large “ observed that the phosphorus, or : receiver expanded into a space e “ rather the pyrophorus of Hom.'

berg, * Continuation of Metherie's Retrospective View.

+ The ancients understood by sulphur what Stahl afterwards caller the inflamma ble principle. But here Hales calls fulphur what Mayer names caufiicon, and Schcele ike matter of beat. .

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* berg, diminished the volume of “ mercurial precipitates I am talk, “ the air in which it burned. He “ing of are not metallie calces ; or, ” concludes that the air of the at: “ Jaftly, that there are calces which “ mosphere enters into the compofi- " may be reduced without the as. — tion of molt bodies, and exiits in " fittance of phlogiston." And a. " them in a solid form, divested of “ gain, “ The experiment: I have ” its elasticity, and of the greater • made oblige me to conclude, that 4 part of the properties we know it " in the mercurial calx in question, “ poffeffes ; that this air is in some “ the mercury owed its calciform “ measure the band of union in na- “ llate, not to the loss of phlogiston, “ ture, that it is the cement of all which it did nat suffer, but to its

bodies, the cause of hardness in " intimate combination with the e. “ fome, and of weight in others." " laftic Auid, the weight of which,

Stahl, who was not acquainted" added to that of the mercury, is with the experiments of Hales, or " the second cause of the augmenvbo difregarded them, never speaks “ tation of weight observable in the of the action of air on the phenome. . precipitates I have examined.” na which the operations of chemist. It is this famous experiment which ry presented to him; he endeavourtho'its author has not been acknow. ed to explain them all by his inflam- ledged, has served as the basis of the mable principle or phlogiston. new doctrine. What M. Bayen af

Such was the fate of this brancú firmed of mercury has been extend: of science, when Venel, Black, Ca- ed to all the metals, to sulphur, to vendish, Priestly, &c. repeated the phosphorus,to charcoal, &c. viz. That experiments of Vau Fielmont, Boyle, their calciform state, or combustion, Hales &c. and shewed that all bo- was not owing to the loss of phlodies contained a very great quanti- gitton which they did not suitain, ty of air, and that atmospheric air but to their combination with the was of prime importance in all the elastic fluid, (or pure air which operations of nature.

Priestly the wed could alone mainIt was then attempted to recon- tain combulion) the weight of which cile this new doctrine with that of being added to their own was the Stahl, and it was said that in the cal- cause of that augmentation of weight cination of metals, the combustion observed by Hales, and others in of sulphur, of phosphorus, &c. the in- metallic calces, and in the prociuas flammable principle was disengaged, of the combustion of phosphorus or and air absorbed.

phosphoric acid, &c. Thus we may But M. Bayen afterwards redu- almost denominate this doctrine the ced the calx of mercury, alone and System of M. Bayen. without charcoal, obtaining a quan. It could not be explained howe. tity of air, which Dr Prieitly found ver by this hypothefis, whence came was pure air. 'An ounce of red pre- the inflammable air which was obcipitate gave, on different occasions, tained from a great number of coma volume of elastic fluid equal to a. bustible bodies, such as, iron, zinc, bout 40 ounces of water, that is to &c. either by diffolving them in say, about 60 cubic inches of air. acids, or by expoling them in gun* These experiments, says he, throw barrels to fire, or by merely keeping ' light on the matter. I will no them in water, &c. Recourse was longer hold the language of Stahl's had to another experiment. “ disciples, who will now either be · M. Macquer having set fire to in“ forced to confine the doctrine of flammable air under a porcelaine pblogiston, or to confess that the dish, obtained a good deal of water.

I repeat:

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repeated the fame experiment with li was repied to this difficulty by inflammable air, produced by fil. another experiment. ings of feel well dried, and expo. Dr Black, in the year 1757, had sed to a strong fire in a small mat- faid that all bodies have not the same frass. I likewise obtained a quanti- specific heat. Meffrs Wilke, Wart, ty of water, and concluded that the &c. supported the lame doctrine. water was contained in the air. M. At lait Crawford made some very Cavendith drew another conclusion nice experiments to determine the from the same experiment. He sup- specific heat of bodies. From these posed that the water obtained was it appeared that pure air, of all the a product of the combustion of the bodies that had been made the fub. inflammable air and pure air, and ject of experiment, con ained the that in general water is composed of greatest specific heat, being to water these two airs.

as 87,000 to 1000. From that time the partifans of The defenders of the new docł. the new doctrine, adopting this lait rine profited by these experiments, hypothesis, exp!ained, by the decomand athrmed that the heat and the polition of water, the origin of all fame given out by different comburthe infiammable ais obtained from tible bodies, did not proceed from metals, from charcoal, &c. they like the bodies which pollefied only a wife profited by an experintent of fm ' quantity of specific or latent M. Wart, who had said that water hear, but were owing to pure air, could be decomposed by iron. Ac- the specific heat of which is so con-. cordingly they contrived to put wa- fiderable. A body does not burn ter into a tube of iron exposed to a except when in combination with white heat, and the inflammable air pure air. This air, losing its aeri.' obtained was owing, according to forın ftate, parts with the great quan.. them, to the decomposition of the tity of heat it contained, which bewater, the pure air of whicii uniting coming free, produces the heat and itself to the metal, calcined it. The the funne. intlaimable air disengaged in the It is evident then that the whole folution of metals in acids proceeds of this new theory, is only an induclikewise, by this doctrine, from the tio; drawn from four principal ex-.decomposition of water, &c. .

periinents. Thus the hypothesis of M. Caven. . 1. The absorption of air in the dish on the constituent parts of air, combustion of bodies, the calcinacoming to support the experiment of tion of metals, respiration, &c. a cirNI. Bayeo, has been used to found cumitance observed by bay, Bayle, a new doctrine.

Hales, &c. But there still remained a difficul 2. The reduction of the calces of sy of some importance: for tho' me. metals without addition of fubftan. tais, felphur, puoipiorus, charcoal, ces, containing the inflammable prin&c. absorb pure air in thcir com- ciple; and at the same time the difbation and calcination, it did not engagement of air according to the follow that the principle, whatever experienent of M. Bayen, it was, which produced the fiame 3. The specific heat of pure air, and the heat, might not be found in according to Crawford. these substances. Therefore even 4. The composition of water, acIhongh they did not contain inflam- cording to Cavendish. mable air, they might be possessed Allthe other experiments brought of some other principle, which might in favour of this system, may be rebe the principle of indammability. duced to onc of these four fundamen

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