134 TRANSACTIONS OF THE [FeB. 27 



generated them ; i^erbaps the study of gases was retarded by 

 lack of inventive skill in handling thena. 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 difiiciilt it must have 

 api^eared to confine, divide, remove from vessel to vessel, 

 examine and manage at pleasure fugitive, incoercible and 

 impalpable fluids like that which we breathe.'' 



In 1G72 Boyle obtained hydrogen gas by the action of acids 

 on iron filings, and showed its combustibility, but seems ta 

 have made no attempt to collect and examine the gas. 



The first scientific experiments in piieumatic chemistrj' 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-nilro et spirilu nilro-aereo, 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. Maj^ow 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 imjiroved by the 

 eminent English botanist, Rev. Dr. Stephen Hales. In his 

 " Vegetable Statics" (1727) he describes an attempt to analj'se 

 the air with many ingepious 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 by a 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 d' Element, 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 



