MEMOIR OF THE LATE DR. HENRY. 121 
published in the Manchester Memoirs for the 
same year (1824), though not adding any facts 
of moment to the prior results of Gay Lussac, 
yet made known some new and exact methods 
of speedily decomposing nitrous oxide and nit- 
rous gas. Thus the constitution by volume of 
nitrous oxide, was determined with singular 
precision by detonating it with carbonic oxide, 
instead of with hydrogen gas; and nitrous gas 
was found to form an explosive mixture with 
olefiant gas. 
It is worthy of remark, that all Dr. Henry’s 
scientific memoirs, which have been hitherto 
enumerated, are devoted to the chemistry of 
aeriform bodies. For this refined department 
of science, Dr. Henry always manifested the 
strongest predilection. Indeed of nine experi- 
mental papers, contributed by him to the Royal 
Society, no fewer than eight are dedicated to 
the gases. At the period when Dr. Henry’s 
interest was first awakened for philosophical 
pursuits, the rapid discovery by Priestley of 
several new gases, and the sanguine hopes in- 
spired by Beddoes of detecting in these subtle 
and hitherto concealed forms of matter power- 
ful remedial agents, urged both physiologists 
and chemists to engage with ardour in pneuma- 
I 
