6 2 Mr. Davy’s Lecture on some new analytical Researches 
refractive ; their affections by electricity are likewise similar to 
those of sulphur ; for the oily bodies give out hydrocarbonate 
by the agency of the Voltaic spark, and become brown, as 
if from the deposition of carbonaceous matter. 
But the resinous and oily substances are compounds of a 
small quantity of hydrogene and oxygene, with a large quan- 
tity of a carbonaceous basis. The existence of hydrogene in 
sulphur is fully proved, and we have no right to consider a 
substance, which can be produced from it in such large quan- 
tities, merely as an accidental ingredient. 
The oily substances in combustion, produce two or three 
times their weight of carbonic acid and some water ; I endea- 
voured to ascertain whether water was formed in the com- 
bustion of sulphur in oxygene gas, dried by exposure to 
potash : but in this case sulphureous acid is produced in much 
larger quantities than sulphuric acid, and this last product is 
condensed with great difficulty. In cases, however, in which 
I have obtained, by applying artificial cold, a deposition of 
acid in the form of a film of dew in glass retorts out of the 
contact of the atmosphere, in which sulphur had been burned 
in oxygene gas hygrometrically dry, it has appeared to me 
less tenacious and lighter than the common sulphuric acid of 
commerce, which in the most concentrated form in which I 
have seen it, namely, at 1.8,55, gave abundance of hydrogene 
as well as sulphur, at the negative surface in the Voltaic 
circuit, and hence evidently contained water. 
The reddening of the litmus paper, by sulphur that had 
been acted on by Voltaic electricity, might be ascribed to its 
containing some of the sulphuretted hydrogene formed in the 
process ; but even the production of this gas, as will be im- 
