IN GASES: HYDROGEN, CARBONIC OXIDE, AND OXYGEN. 
G15 
Experiments on the influence of initial pressure and of the length of the column of the 
gases on the division of the oxygen. 
In the first experiment a mixture of carbonic oxide and electrolytic gas, containing 
70 parts of carbonic oxide to 30 of hydrogen, was exploded in two portions, the first 
under 120 millims. pressure and the second under 400 millims. pressure. In the first 
portion the ratio of carbonic acid to steam produced was 1 '2, and in the second portion 
■8. A nearly similar mixture was divided into three portions. The first, exploded 
C O 
under 100 millims. pressure, gave 1’24 for the ratio 2 > ^ le second, exploded under the 
Xl.vd 
same pressure, but only forming a column half as long as the first portion, gave 1‘06 
C O. 
for the ratio rj—r ; the third, forming a column equal to the first, but exploded under 
HqU 
225 millims. pressure, gave ’85 for the ratio. 
A set of experiments Avas then made with different portions of the same mixture 
under nearly constant conditions of temperature and pressure, but with variations in 
the length of the column of exploded gases. 
In these and all the subsequent experiments the following method of drying the 
apparatus, charging the eudiometer and calculating the results, was adopted. The 
whole apparatus being emptied of mercury, air was drawn for twelve hours by a pump 
attached to the top of the barometer, through two long horizontal drying tubes 
charged with oil of vitriol, through a bent tube passing under the mercury in the trough 
and opening into the laboratory tube, thence through the capillary connecting tubes 
down the eudiometer and up the barometer. The taps at the top of the barometer 
and at the bottom of the eudiometer were then closed and the drying tubes were 
attached to the mercury reservoir. Dry air was then drawn for some hours through 
the reservoir and long connecting tube, and up the barometer. The mouth of the 
reservoir being closed, the drying tubes were again connected with the laboratory tube, 
and dry air was drawn through the eudiometer and barometer while the water in the 
jacket surrounding them Avas heated to 90°-100° C. After some time the tap at the 
top of the barometer was closed and hot mercury poured into the reservoir. By raising 
the reservoir the hot air in the eudiometer and barometer was expelled. The reservoir 
was lowered until the eudiometer and barometer Avere empty. As the mercury ran 
down, bubbles of air always rose from the sides of the tubes and from the lower tube 
connected Avith the reservoir. The lower stopcock being closed the air remaining in 
the laboratory tube was allowed to pass over into the eudiometer, the laboratory tube 
being thus completely filled with dry mercury. The mercury was again run up to the 
top of the eudiometer and barometer and the air expelled, and once more the mercury 
was run down to extract bubbles of air sticking to the glass. On again running up 
the mercury and letting it overflow from the barometer and eudiometer all traces of 
air were got rid of. The hot water in the jacket Avas then replaced by a constant 
