RESEARCHES 0V SULPHUR AND PHOSPHORUS* 35 



of OX i gen in volume ; from which I am inclined to believe, 

 tliat sulphureous acid consists of sulphur dissolved in an 

 equal volume of oxigen; which would give the number as 

 13*7* nearly, considering the acid gas as containing 1 por- 

 tion of sulphur, and 2 of oxigeu ; and these estimations 

 do not differ from each other materially. 



I have made several experiments on -the combustion of Weight of an 

 phosphorus iii oxio^en aras. From the most accurate, I am ulfmate atom 

 • r J 1 V 1 n 1 1 1 1 . ofphospho- 



inciiuea to conclude that 25 oi phosphorus absorb in com- rus. 



bustion about 34 of oxigen in weight; and considering 

 phosphoric acid as composed of 3 proportions of oxigen 

 and 1 of phosphorus, the number representing phosphorus 

 will be about l6'5, which is not very remote from the num- 

 ber that may be deduced from the composition of phos- 

 phoret of potassium. 



The numbers, which represent the proportions in which Sulphur and 

 sulphur and phosphorus unite with other bodies, are such, ^^y^conJ^a 

 as do not exclude the existence of combined portions of oxigen and hi- 

 oxigen and hidrogen in their constitution ; but it may be Jf'*^!^ *^°^^ 

 questioned, whether the opinion which I formed, that the 

 inflammable gas disengaged from them by electricity ii 

 necessary to the peculiar form in which these bodies exist, ^ 

 is not erroneous. Phosphorus, as 1 have stated in the Ik^t 

 Bakerian lecture, is capable of forming a solid hydruret : 

 and a part of the sulphur distilled from iron pyrites is 

 usually of a soft consistence, and emits the smell of Sul" 

 phuretled hidrogen, and probably contains that body. It and probably 

 is not unlikely, that in all cases phosphorus and sulphur i" "p case per- 



: ,5, ,, fectlyfree 



* The estimation from the composition of sulphu;etted hidrogeii must 

 be corsJdered as most accurate, and that from the formation of the sul- 

 phured of poiu>siiun as least accurate: for it was only by combining 

 sulphur and potaisium m small proportions, and ascertaimng in what 

 cases uncombined sulphur could be distilled from the compound, that 

 1 giiued my conclusions concerning the composition of the sulphu.et of 

 potasiiium. 



In the last Bakerian lecture, I have estimated the specific gravity of 

 sulphuretted hidrogen at S6 grains the 100 cubical irjches, whicb was 

 not far from ihe meiii, between the estimations of Mr Kirwan and 

 Mr Thenard. According to lliis experiment, sulphuretted hidrogen is 

 composed of 1 portion of hidrogen, represented by 1, and 1 of sulphur 

 represented by *lb 4. » 



D2 contain 



