Technical Chemistry. 119 
It is formed also when the vapor of chloroform is brought in contact with 
red hot copper; and is moreover a constituent part of ee gas, 
Of the —_ sources, ether furnishes it in the greatest abundance. In 
whichever of t methods t e gas may have been’ prepared, howaver, it 
is always pein with a large quantity of other gases, from which it must 
be separated in the manner indicated by Beettger before it can be ob- 
Acetylene is a colorles & s gas, somewhat readily soluble in water, having 
a disagreeable ms oie odor, and burning with a very luminous 
and smoky flame. Its sp. gr.=0°92; it has not been liquified either by 
eold or ng "Mixed with chlorine a a = a ed 
d 
vapor, 
In general the properties of this gas are similar to those of olefiant gas 
(C,H,); and by combining with bromine, sulphuric acid, the elements 
of water, and with hydrogen, it forms compounds parallel to those formed 
in similar cases by olefiant gas. 
[In a technological point of view this gas is of great interest; for not 
only is Berthelot’s observation of the first importance in itself as a contri- 
bution to the chemistry of gas lighting, but further investigation of the 
subject will no doubt lead to the elucidation of several of the vexed ques- 
tions upon which gas engineers are at variance. For example, the fact 
that a quantity of useful gas—probably much more Juminous than an 
bat bulk of olefiant gas, is produced when the latter is strongly heated, 
ust be a most acceptable suppcrt to those who advocate * high temper- 
sent as the best system of gas making ;—as it must also \ materially 
modify, the prevailing notion that the luminiferous properties of olefiaut 
gas are entirely destroyed by such treatment. In a word, those who from 
theoretical premises — sate se asco that th employee ent of 
posed this system, wens mist ey their argument.* 
Again, the kno owledge that a luminiferous gas so readily soluble as 
_ acetylene occurs in coa! gas is a subject most worthy the consideration o 
_ those gas engineers who advocate the use of much water in the purifica- 
tion ,—or who, in the terse langu age of “the opponents of their system, 
“would ‘scrub’ the life out of the 
occurrence of ag Sach ee no she bt of some of its homol ogues, 
in illuminating gas is moreover ano other evidence of the error, still 
quently fallen apie by chemical writers, of attributing all the lu minif- 
* We would in no wise affirm either that fhe researches of Berthelot and Boott- 
ger have demonstrated oe excellence of the 
it would be advanta: in 
