071 the Nature of certain Bodies. 1 7 



as In the last instance ; and, when acted on by a littleivater 

 holding nuiriatic acid in solution, there wfefe evolved from 

 it five cubical inches only of sulphuretted hydrogerii 



Both these experiments concur in proving the existence of 

 a principle in sulphuretted hydrogen, capable of destroying 

 partially the inflammability of potassuini. and of producing 

 ypon it all the effects of oxygen ; for, had the potassium 

 combined merely with pure combustible matter, it ought, as 

 will be seen distinctly from what follows, to have evolved, 

 by the action of the acid, a volume of sulphuretted hydro- 

 gen, at le&st equal to that of the hydrogen which an equal 

 weight of uncombined potassium would have produced by' 

 its operation upon water. 



Sulphuretted hydrogen, as b^s been long known to che- 

 mists, may be formed by heating sulphur strongly in hydro- 

 gen gas. 1 heated four grains of sulphur in a glass retort> 

 containing about twenty cubical inches of hydrogen, by 

 means of a spirit lamp, and pushed the heat nearly to red- 

 ness. There was no perceptible change of volume in the gas' 

 after the process ; the sulphur that had sublirhed was unal- 

 tered in its properties, and about three cubical inches of an 

 elastic fluid absorbable by water were formed : the solution' 

 reddened litmus, and had all the properties of a solution of 

 pure sulphuretted hydrogen. Now if we suppose sulphu- 

 retted hydrogen to be constituted by sulphur dissolved in its' 

 unaltered state in hydrogen, and allow the existence of oxy- 

 gen m this gas j its existence must likewise be allowed in 

 sulphur, for we have no right to assume that sulphur in sul- 

 phuretted hydrogen is combined with more oxygen than iri 

 its common form : it is well known, that when clectricat 

 sparks are passed through sulphuretted hydrogen, a consi- 

 derable portion of sulpliur is separated without any alteration 

 in the volume of the gas. This experiment 1 have made 

 more than once, and I found that the sulphur obtained, xii 

 fusibility, combustibility, and other sensible properties, did 

 not perceptibly differ from common sublimed sulphur. 



According lo these ideasy the intense ignition produced 

 by the action of sulphur, on potassium and sodium, must 

 not be ascribed merely to the affinity of tlie metals of the 



Vol. 34. No. 135. July 1809. V> alkalies' 



