160 Proceedings of the Royal Society of Edinburgh. [Sess. 
assumed as 100 per cent. Partington does not state whether he corrected 
for the error that so long escaped the vigilance of Berkeley,* who pointed 
it out some years after Partington’s work ; nor even whether the more 
obvious correction for change of air pressure due to head of water in his 
saturator was duly applied. 
Princeton University, 
August 1920. 
* Nature , xcv, p. 34 (1915). 
{Issued separately October 12, 1920.) 
