200 



Scientific Proceedings, Royal Dublin Society. 



shows that the force causing the mixing has become so extremely small as to be 

 capricious in its action. 



100 



60 



o60 



iArO 



20 



to 



40 



60 80 



Time in Hourj 



100 



120 



Fig. 2. 



In considering the possible agencies which could affect the process under 

 the experimental conditions, it must be remembered that these were kept as 

 constant as possible. 



The mass of gas used was completely enclosed, and both gas and water were 

 maintained continually at the same temperature. The gas was given the correct 

 humidity for the working temperature before admission to the apparatus, and 

 therefore evaporation from the surface layers of the water was prevented. The 

 possibility of slight convection currents, due to cooling of the surface layers, 

 which might occur when the water is exposed to the atmosphere, is eliminated. 



All the more obvious causes which might produce mixing have thus been 

 excluded in these experiments, and the fact that it is present shows that the 

 cause must be more fundamental in its nature, and further careful experiments 

 will be necessary to discover its precise nature. 



Whatever the cause, these experiments clearly show that pure distilled 

 water exposed to oxygen at a uniform steady temperature absorbs the gas in such 

 a way as to indicate that very slow mixing of the water occurs even imder these 

 conditions during the early stages of the absorption, but that towards the 

 saturation point this mixing tends to become uncertain in its action. 



Chemical Laboratory, College of Science, Dublin. 



