94f 



ON THE COMPOUNDS OF SULPHUR AND OXYGEN. 



The impregnat- 2. A current of fulphurous acid gas was paflbd through a 



tfrifef^dd ' s' ^^'"^^ quantity of water till the liquid refufed to a^forb any 



gravity 1.0513. niore. The tafte of the water thus faturated, was^intenfely 



Slight heat d if- acid and fulphureous, and its odour exceffively ftrong. The 



engages eaci • |pgp|^j, gravity at the temperature 68? was 1.0513 ; the heat 



of the hand was fufficient to occafion an extrication of gas. 



When moderately heated, it frothed violently, and exhaled 



the denfe blue fmoke which ufually indicates the prefence of 



fulphurous acid. When boiled down in a retort to half its 



bulk, it loft its fmell, but ftill continued (lightly acid. Hence 



it obvioufly contained fulphuric acid. 



Analyfis of ful- 3. In analyfing the different fulphiles, I have not found 



futio"*of fuL °' barytes anfwer fo well as I was led to exped from the experi- 



phiirous acid nicnts of Fourcroy and Vauquelin ; the folubility of fulphite 



portion of fuU^ of barytes in water is fo confiderable, that precifion by means 



jphuric acid, of it is fcarcely to be looked for. But nitrate of lead yields' 



with the alkaline and earthy fulphites a white infoluble powder 



of fulphite of lead, which maiy be dried in the temperature of 



300*' without decornpofition, and is then compofcd of about 



25 fulphurous acid. 

 j^ 75 yellow oxide of lead. 



100 

 One hundred parts of the above liquid fulphuroiis acid 

 yielded, with nitrate of lead, a precipitate indicating the pre- 

 fence of 6.15 parts of fulphurous acid. Another hundred 

 parts, boiled down to one half in a retort, yielded, with muriate 

 of barytes, a precipitate indicating the prefence of 0.34 ful- 

 phuric acid. Therefore, 100 parts of my liquid fulphurous 

 acid contained about 



5.81 fulphurous acid, 



0.34 fulphuric acid, 



6.15. 

 So that the fulphuric acid amounts nearly to -J^ of the ful- 

 phurous. The prefence of this acid is a proof of an affinity 

 between fulphurous acid gas and fulphuric acid ; for the gas 

 was pafled through an intermediate vefl'el before it reached 

 the water. 

 This cofitamina- 4^ 'phg proportion of acid combined with water in the li- 

 lendtT^t water qui^ fulphurous aoM was rather lefs than 7 ; yet, when water 

 lefs capable of [^ plunged into a large column of gas, we have feen that it 

 abforbing ful- abforbs- 



phurous gas. 



