Notices respecting Xew Beth';. 269 



« Now, reckonina; that for the production of each mea- 

 sure of carbonic acid gas, an equal measure of oxygen gas 

 is employed, then by deducting the numbers in the third, 

 column iVom the corresponding ones in the second column, 

 we find the number of the remaining measures which have 

 dlsippeared in saturating the hydrogen of each gas ; and as one 

 measure of oxvgen saturates two of hydrogen, double that 

 number of mea'sures is the volume which the hydrogen con- 

 tained in that gas would occupy if expanded to its usual state. 

 Thus, in the combustion of the gas from coal, of 60 mea- 

 sures of oxygen gas employed, 35 measures have gone to the 

 formation of carbonic acid gas, and 25 measures have dis- 

 appeared with the hydrogen; double this quantity, 50 

 measures, is therefore the quantity of hydrogen contamed 

 in this gas. Agreeable to Mr. Henry's opinion, that tlie 

 degree of illuniination depended on the quantity of inflani- 

 mable matter contained in the gas, he found that the quan- 

 tity of light evolved by each gas was, as nearly as could be 

 judged, in proportion to the quantity of oxygen required for 

 its combustion and detonation in a close vesse'r: so that, 

 agreeable to the foregoing table, the gas from moist charcoal 

 ntanifested least splendour, whilst the olefiant gas exceeds all 

 the rest in brilliancy as well as in violence of detonation. 



<' Mr. Henry also concludes that the inflammable gases 

 are mixtures of a very few simple ones. Gas from coals he 

 supposes to be hydrocarburet with some carbonic oxide, and 

 a small portion, perhaps, of olefiant gas : from charcoal, car- 

 bonic oxide, with hydrogen and a little hydrocarburet ; from 

 oil and from wax, pure hydrocarbnrets ; except that the first 

 contains one-eighth, and the latter one-fourth, of olefiant gas. 

 'Jhe hydrocarburets from ether and alcohol he also found 

 contained this gas ; from the various admixtures of which, he 

 thinks, proceeds that diirerenco which Induced Mr.Cruick- 

 shank to suppose so many diOVrent sp',cics of carburetted 

 hvdroL'en/' 



Jn 



