Adeney — Dissolved Gases and Fermentative Changes. 561 



to prevent the escape of the disengaged gases from the bottle in which the solution 

 was kept. 



The conditions which give rise to the maximum disengagement of gases from 

 liquids kept in bottles, in the manner I have already explained when describing 

 the method of experiment adopted, and apparatus employed for this investigation, 

 are, first, a considerable rise of temperature above the initial point, during which 

 the liquid will expand, and small quantities of it be forced out of the bottle between 

 the neck and the stopper, followed by a considerable fall, when the liquid will con- 

 tract, and, if the stopper be well ground, a small space will be formed in the bottle 

 containing gases previously dissolved, and will be more or less steadily main- 

 tained, since the bottle is immersed in water, neck downwards, so long as the 

 temperature remains below the maximum point to which it was formerly raised. 

 The relation between the quantity of each gas disengaged in this way to that 

 remaining in solution will practically vary with the temperature, according to 

 Henry's law. 



As a practical illustration of the influence of variation of temperature upon 

 solutions kept under the conditions described, I may here give an extreme case, 

 viz. an experiment with tap-water kept for a period of fourteen months. 



This experiment was started on the 2nd February, 1893, when the tap-water 

 before bottling was violently shaken up with air in a large vessel. After this 

 operation the water was allowed to stand until quite free from air-bubbles. Its 

 temperatm-e was then found to be 10° C. A bottle was carefully filled with a por- 

 tion of the aerated water, another portion being immediately afterwards trans- 

 ferred to the laboratory flask of the gas analysis apparatus. On April 3rd of the 

 following year the contents of the bottle were examined. A bubble of gas, about 

 6 CCS. in volume, was found to have been formed. The gases in the bubble were 

 collected over fully aerated distilled water, and immediately afterwards transferred 

 to the laboratory vessel of the gas analysis apparatus, measured, and analysed ; 

 the water in the bottle was not examined until next day, in order to allow time for 

 the distilled water, which had replaced the disengaged gases, to diffuse equally 

 through it. During this time, it need scarcely be said, the bottle was kept immersed 

 in water. 



The temperature at the conclusion of the experiment was 13°-8 C. 



The results of the analysis of the disengaged gases were as follows : — 



Total volume at 0° C. and 760 inm. Bar, .... 5-8414 c.cs. 



Volume of oxygen „ „ .... 1-0058 



Volume of nitrogen, 4-8356 



Volume of carbon dioxide, 



