SULPHUR AND PHOSPHORUS. S57 



three of it in volume absorbed more than five in volume of 

 oxygen, and a little phosphorus was precipitated. 



When potassium was heated in contact with it, its volume 

 increased rapidly till it became double, and then no further 

 effect was produced. The potassium was partly converted 

 into a substance having all the characters of phosphuret of 

 potassium j and the residual gas i.bsorbed the same quantity 

 of oxygen by detonation as pure hydrogen. When sulphur 

 was sublimed in the g03 over mercury, the volume was like- 

 wise doubled j a compound of phosphorus and sulphur was 

 formed, and the elastic fluid produced had all the characters 

 of sulphuretted hydrogen. 



It appears froin these experiments, that the peculiar gas The jas con- 

 consists of 45 of hydrogen in weight to 22'5 phosphorus; ^"^^* "^ ^j'^2'5 

 and its composition being known, it is easy to determine the phosphorus, 

 composition of the hydrophosphorous acid, and likewise the 

 quantity of oxygen required by a given quantity of phospho- 

 rous acid to be converted into phosphoric acid j for, for every 

 volume of gas disengaged, a volume of oxygen must have 

 been fixed in the phosphoric acid. 



And calculating for 1/4 grains, 30 parts of oxygen must 

 be fixed in the 150 parts of phosphoric acid, and 20 parts of 

 phosphorus disengaged in combination with 4 parts of hydro- 

 gen j and on the idea of representing the proportions in Taking hvdro- 



which bodies combine by numbers, if hydrogen be considered ?^" ^^ m.ity, 

 1 r . - , , the propor- 



as unity, and water as composed or two proportions or hydro- tiona! no. of 



gen, 2, and one of oxygen 15*, phosphorus will be repre- combustion 



, , of phos. will 



sentedby20. be20. 



When the compounds of chlorine and phosphorus are acted compound of 

 on by a small quantity of water, muriatic acid gas is disen- chlor. and 

 gaged with violent ebullition, the water is decomposed, and it |^ ^ water o-ive 

 is evident that for every volume of hydrogen disengaged in mur. acid gas 

 combination with the chlorine, half a volume of oxygen n^us: '^"^^i^^'j^^.r^'^yj^j^ 

 be combined with the phosphorusf ; and the products of the the phos. 

 mutual decomposition of water, and the phosphoric compounds 



* Supposing 100 cubical inches of the gas to weigh 27 {grains. . 



27 — 4-5 the weight of 200 cubical inches of hydrogen = 22-5 fjrains. 



f This mode of estimation is the same as that I have adopted on a 

 former occa•~^ion, except that the numbej representing oxygen ie 

 doubled to avoid a fractioial part. 



of 



