396 Eaperiments.on the Gas from, Coat. 
Olefiant gas I found to be one of the pro- 
ducts of the distillation of oil and of bees’ 
wax, and was led, therefore, to suggest, that 
the wick of alamp or candle, surrounded by 
flame, is to be considered as a bundle of, igni- 
ted capillary tubes, into which the melted 
inflammable matter is drawn, and there re- — 
solved, not, into a condensible vapour, but 
into olefiant and carburetted.. hydrogen 
gases.. In the, gas.from coal, also, I detected 
the. presence of olefiant. gas, by the tem of 
the action.of chlorine. 
. In, the second ;series of ecuonenential I 
on to distillation, on.a small seale,.va- 
rious, kinds of coal, from different, parts. of 
the: kingdom, The aériform, products, at 
different, siages of the process, were, kept 
apant, and were separately analyzed. From 
coal, distilled, in, small iron tubes, or, retorts, 
which, when filled, were placed, at once ina 
low red heat, small quantities,of, sulphuretted 
hydrogen and carbonic acid gases came over 
at first, in mixture with the other gases, but 
in a gradually diminishing proportion, till 
at length, in the last products, they were not 
discoverable at all. The production.of ,ole- 
fiant gas observed the same order, and a 
* Phil. Trans, 1808. page 282. 
