15 On some Jieiv anahjtical Researches 



dissolv ed in the g<*is, and I ventured to draw no conclusion 

 till \ had tried the experiment in an unobjectionable manner. 



I heated four grains of potassium in a retort of the ca- 

 pacity of twenty cubical inches; it had been filled after the 

 u-^ual processes of extiaiistion with sulphuretted hydrogen, 

 dried bv means of n)uriate of lime that had l)ccn heated to 

 whiteness; as soon as the potassium fused, white fumes 

 vert copiouslv emitted, and the potassium soon took fire, 

 and burnt with a most brilliant flame, yellow in the centre 

 and red t(»wards the circumference*. 



'i'lie diminution of the volume of the elastic matter, in 

 this operation, did not equal more than two cubical inches 

 "and a half. A very small quantity of the residual gas only 

 was absorbable by water. The non- absorbable gas was hy- 

 drogen, holding a minute quantity of sulphur in solution. 



A yellow sublimae hncd the upper part of the retort, 

 which proved to be sulphur. The solid matter formed was 

 red at the surface like sulphuret of potash, but in the inte- 

 rior it was dark gray, like sulphuret of potassium. The 

 piece of the retort containing it was introduced into ajar 

 inverted over mercury, and acted upon by a jrmall quantity 

 of dense muriatic acid, diluted with an equal weight of 

 water, ivhen there were disengaged two cubical inches and a 

 quarter of gas, which proved to be sulphuretted hvdrogen. 



In another experiment, in which eic;ht grains of potas- 

 sium were heated in a retort of the capacity of twenty cubi- 

 cal inches, containing about nineteen cubical inches of sul- 

 phuretted hydrogen, and a cubical inch of phosphurctted 

 hvdrogen, which was introduced for the purpose of absorb- 

 rig the oxygen of the small quantity of common air admit- 

 ted hv ihc stop-cock, the inflammation took p'lace as before, 

 there was a similar precipitation of sulphiir on the sides of 

 the retort; the mass formed in the place of the potassium 

 was orange externally, and of a dark gray colour internally, 



• In the Monifeur, May 27, 1808, in the account of MM. Gay Lii«ac'« 

 anJ 'I'henard's experiments, it is mentioned, that potassium absorbs the sul- 

 phur snd a part of the hydrof en of sulphuretted hydrogfcn ; but the phano- 

 in«na of inflamnuiion is not roentioucJ, nor arc the results described. 



26 



