484 Ov/tftMilioitj upon EffiBt fuppofird 



ter of the glacial oil of vitriol, but a folution of thefe cryflals in water. The exiftence of 

 vitriolic aciil in a fluid form implies necefl'arily the co-exl(lence of water. The formation 

 of tlic water in the inflammation of fulphur appears to have been palTeil over by both 

 parties, though the interpretation of tliis part of the proccfs feems to me to furnifli the 

 means of reconcilement. 'Ihus, while the pure fulphur combines with one portion of 

 oxygcne to make the acid, the hydrogene or phlogiilon unites with another parcel of it to 

 form the water in which the acid dilTolves. Common brimflone then is not a fimple fub- 

 ftance, but is a phlogi/turc cf fulphur. And this is confirmed by the faft that, where cora- 

 buftion is reftrained, the fuiphur may be refolved into hepatic gas; the phlogifton turning 

 with caloric into inliammable air and diflblving force of the fulphur. The formation of 

 common hepatic gas feems to evince the fame thing ; for whik the potafh feizes the ful- 

 phur, the hydrogene or phlogifton is fet loofe, turns with caloric to hepatic gas, and 

 fnatches, as it departs, a portion cf the fulphur from the alkalL Thus it appears that the 

 two fyfteras arc reconcileable with each othet. When the Old Chemifts talk of phlogifton, 

 they fliould define it to be that thing which burns with flame, and when united to oxygene 

 forms water. When the new ones make experiments on fulphur, they ftiould remember 

 that the common material called by that name is not the abftraft, pure, uncombined 

 elementary thing they intend in their nomenclature. 



2. In like manner the phenomena attending the inflammation of phofpliorus feera to 

 have been as negligently interpreted. Plilogifton added to phofphorlc acid was faid by 

 fomc to conftitute phofphorus ; while oxygene added to phofphorus made phofphorlc acid 

 in the opinion of others. But thefe were a kind of chemical theorems, true only in the 

 abftrafl experiments. We find that phofphorus burns with Jlami, and ivater is exhibited 

 during the procefs. All that needs be faid about it is, that in common circumftances phof- 

 phorus, though capable of exifting per fe, has a very ftrong attra£lion for hydrogene or 

 phlogifton; and in ordinary cafes attaches more or lefs of it to itfelf. During its inflam- 

 mation part of the oxygene, as in the cafe of the fulphur, combines with the phlogifton 

 into water ; and another part of it joins the oxygene to conftitute the acid. In eftimating^ 

 the "uihok of the procefs, tlie candid partifans of both fides will allow that the fubftance 

 under confideration parts with its phlogifton and borrows oxygene, and thus water and the 

 acid dilTolved in it are formed. 



Where is the harm of owning that common phofphorus contains a portion of hydrogene 

 united with it .' It does not invalidate the modern theory : but it fliews that the objecllons 

 of the ancient doctrine were not frivolous, as they have by fomc been deemed to be; but on 

 the contrary very fubftantial, and not capable of reconcilement upon any other plan, that I 

 know, than the one herein fuggefted. 



3. Zinc may be abftradedly confidered as a fimple body, and with profriety pbced as 

 fuch in the catalogue. Commonly, however, it is prefrnted to us in clofe connexion with 

 hydrogene, for which its attraiflion is fo ftrong that they commonly appear in tlic form of 

 a phlogifure of zinc. When that compofition is employed for experiments, it is very eafy to 

 conceive how, when fuch zinc is expofcd to a fufEcient heat in an open fire, the plilogifton 

 diflodged, and immediately becoming phlogiftous gas or inflammable air, fhall take upon itfelf 

 the form of flame and conftitute water; while the oxygene combines with the metal into 

 a white oxyde, the fio-A'ers of zinc. So if tlie fame compound be diflblvcd in fulphuric 



acid, 



