134 TRANSACTIONS OF THE (Fes. 27 
generated them ; perhaps the study of gases was retarded by 
lack of inventive skill in handling them. Dr. Beddoes writing 
of Mayow, and reflecting on this point, uses the following 
language: ‘‘To be sensible of the merit of these contrivances 
of Mayow, we have only to recollect how difficult it must have 
appeared to confine, divide, remove from vessel to vessel, 
examine and manage at pleasure fugitive, incoercible and 
impalpable fluids like that which we breathe.” 
In 1672 Boyle obtained hydrogen gas by the action of acids 
on iron efilings, and showed its combustibility, but seems to 
have made no attempt to collect and examine the gas. 
The first scientific experiments in pneumatic chemistry were 
made by John Mayow, an Oxford physician, born in 1645 and 
died at the age of 34 years. In 1669 he published a 
work entitled De sal-nitro et spiritu nitro-aéreo, in which he 
figures his apparatus and describes his methods. To 
confine and study any gas, the air, for example, he inverted 
a cucurbit in a pan of water, used a siphon to establish the 
level of the water within and without, and introduced a shelf 
into the wider part of the cucurbit, from which he hung 
substances whose action he examined. He used a burning glass 
to ignite substances, camphor for example, placed in the cucur- 
bit ; he also introduced a mouse in a cage supported on a tripod 
under the cucurbit. He adopted an ingenious plan for trans- 
fering gases from one vessel to another, shown in the engraving 
that accompanies his rare treatises. Mayow failed to distinguish 
different gases, but was the pioneer in the method of manipula- 
ting them. Of his anticipating later theories of combustion we 
make mere mention, as our theme excludes theory. 
Mayow’s contrivances were somewhat improved by the 
eminent English botanist, Rev. Dr. Stephen Hales. In his 
‘‘ Vegetable Statics” (1727) he describes an attempt to analyse 
the air with many ingenious devices. Hales heated substances 
in a retort communicating by means of a siphon with a receiver 
consisting of a flask inverted in a vessel of water, the flask 
being supported bya cord from above. He heated nitre in this 
way, and especially noted the permancy of the air obtained, 
but failed to examine the properties of the air ; and he failed to 
differentiate the several gases obtained by his methods. 
Even before Hales, however, an obscure physician in France, 
Moitrel @’ Hlément, had invented improved methods of handling 
gases. In 1719 he published a little pamphlet containing lucid 
instructions for measuring and collecting gases; especially 
noteworthy is the separation of generator and receiver first 
suggested by him. The poor physician’s skill was unnoticed by 
