132 
ON THE MANUFACTURE OF GAS. 
and described by Cruden as a very rich perfume, had re- 
ference to sanitary as well as devotional intentions. The 
use of strong aromatic perfumes was always general in 
countries much exposed to infectious influence, as we read 
in the inspired poetry of David, "All thy garments smell 
of myrrh, aloes, and cassia; " and the practice of embalm- 
ing the dead (as the etymology of the word imports) had 
much to do with balsamic and other odorous substances. 
I mention perfumes more particularly than the other 
"anticatalytic " agents, because, as a chlorine generator 
could not very conveniently bo carried about the person, 
perfumes offer an agreeable, and, I suspect, in many cases 
an equally efficacious antidote with chlorine against the 
influences of infection. 
I remain, sir, your obedient servant, 
V William Gallard. 
ART. XXXV .-ON THE MANUFACTURE OF GAS. 
By Andrew Ure, M. D., F. R. S. 
To the Editor of the Pharmaceutical Journal. 
The observations made in your last number, under the 
head of " Improvements in the Manufacture of Gas," 
though correct in general, require certain modificalions. 
The great fall in the price of the London gas cannot fairly 
be ascribed to any considerable recent improvements in the 
quality or quantity of gas produced from a ton of coals ; but 
is almost entirely due to the economy of the fuel used in 
decomposing the coal. At one period, not only the whole 
coke of the decomposed coal in the retorts was expended in 
