On definite Proportions. 89 



Now, if three grammes of sulphite of baryta contain 

 •S653 of sulphurous acid, and 3- 17 gr. of the sulphate, 

 into which ihev are changexl by oxygenization, imply the 

 presence of 4374 gr. of sulphur, the remaining .4279 gr. 

 of the acid must be oxygen. Consequently 100 parts of 

 sulphur take up 97*83 of oxygen, in order to form sul- 

 phurous acid ; and this acid consists of 



Sulphur 50*55 10000 



Oxvgen 49*45 97 83 



If we took for the sulphate 33*9 of acid and 66*1 of 

 earth, the 3 grammes of sulpliite would appear to contain 

 •86-21 ot acid, and '4361 of sulphur; whence the propor- 

 tions would become 



Sulphur 50-59 100-00 



Oxygen 49*41 97*69 



[The author seems to have omitted to notice some other 

 determinations, as having been deduced from inaccurate 

 suppositions resptctins the component parts of the sulphate 

 of barvta. Mr. Chenevix converted 14-4 parts of sulphur, 

 by means of nitric acid, into 100 parts of sulphate of 

 barvta, to which he attributed only 23*55 of sulphuric acid, 

 and hence concluded that the acid consisted of 6i*5 of sul- 

 phur, and 385 of (ixytren. But, if we employ Mr. Berze- 

 lius's deterniination of the proportions of the sulphate of 

 baryta, it will appear that 14 4 sulphur must have afforded 

 at least 34 parts of suljihuric acid ; whence the sulphuric 

 acid should consist oi' 4'2'4 of sulphur, and 57*6 of oxvgen. 

 But these experitiients bv no means agree with each other 

 so well as those of Mr. Eerzelius. Mr. Berihollet's ana- 

 lysis, in the Memoirs of the Institute for 1806. which gives 

 •5385 of sulphur, and -46! 5 of oxygen, led Mr. Gay-Lussac, 

 in his interesting investigations lespectmg the decomposi- 

 tion of the sulpharic compounds bv heat, to the erroneous 

 conclusion, thai the sulphurous acid contains only 50-61 

 of oxygen to 100 of sulphur, instead of at least 95*86, 

 which IS the proportion determined by Berzelius. The 

 same chemist, in his remarkable essay on th.e combinations 

 of gases, has assigned to the sul|-)hur;c acid 42-016 of sul- 

 phur, and 57'9Hi of oxygen, and to the sulphurous, 

 52-083 of sulphur, and 47 9T2 of oxygen ; but his data re- 

 quire some very considerable corrections. — Gilkrrt.] 



Since 100 parts of sulphur are combined in the sul- 

 phurous acid with 97*83 of oxvi.;en, and in the sulphuric 

 with 116-427, the latter numb-r being very nearly half as 

 much more as the fcjrmer, since 97*83 + 4&-9f)= 146 74, it 

 follows that the same quantity of sulphur takes up in the 



sulphuric 



