128 EXPERIMENTS ON SULPHURIC ACIfir. 



them fo ; but I fay merely, that we have no proof. It would 

 indeed be fetting narrow bounds to the perfection of nature, 

 to aflert, that no combuftible body could, when faturated with 

 oxygen, aflume, of itfelf, the ftate of liquidity ; or that the 

 oxide of the particular fubftance, called hydrogen, muft be 

 prefent to confer that property. Doubtlefs, fulphuric acid 

 may, as well as water, contain, in itfelf, fojuft a proportion 

 of fpecific heat, as to remain liquid at the temperature of our 

 globe, and under the preflure of our atmofphere. But, both 

 water and fulphuric acid being eafily volatilized, and having a 

 powerful affinity for each other, it is noteafy, if even poffible, 

 by diftillation, to feparate them with fufficient accuracy, in 

 experiments of delicate inquiry. A fecond fource of error, 

 therefore, remained open in this branch of the calculation, 

 which gave the proportion of 23.43 of fulphur, as that con- 

 tained in 100 parts of fulphate of barytes. 

 Exp. too fat' However, before I would allow myfelf to call in queftion 

 fieTbjhitric ! " ^ ucn authorities as thofe I have quoted, I inftituted the fol- 

 acid j lowing experiments : In a tubulated glafs retort, I put 100 



parts of purified fulphur, and poured upon them ftrong nitric 

 acid. A quilled receiver, plunging into a Woulfe's apparatus, 

 was adapted to the retort ; and, all being well luted, I pro- 

 ceeded to diftil. The liquor, which came over, was poured 

 back feveral times upon the fulphur, until the whole was dif- 

 folved. The water, which had come over, and that, through 

 which the nitrous gas, produced during the operation, had 

 pafled, were eflayed for fulphureous acid, and no traces of it 

 could be found. No fulphur had been volatilized; therefore 

 no fufpicion could remain, that all was not converted into ful- 

 and theactd phuric acid. The liquors, which were in the various parts of 



thrown down t j apparatU c we re united ; and to them was added a fuffi- 

 with nitrate or t r > > 



barytes. cient quantity of nitrate of barytes. The whole was evapo- 



rated gently ; becaufe, though I am well acquainted with the 

 very little folubility of fulphate of barytes, I well know that 

 nitric acid will retain a fmall portion of it, particularly when 

 Rcfults, that formed in a liquor where that acid abounds. In a firft experi- 

 phate of barytes ment, I obtained 694 from 100 of fulphur, in a fecond, 348 

 contain 14.5 f r om 50, and in a third, 347 from the fame quantity. But 

 alfo the oxygen. tne nm P^ e ru Ie of three reduced thefe quantities to 14.6, or 

 14.4 per cent, of fulphur, contained in fulphate of barytes; 

 a difference wholly to be neglected. If, therefore we take 

 2 14.5 



