102 THE ROYAL SOCIETY OF CANADA 



calculated, making use of Van der Waals equation to obtain y for the 

 real gas. The values of y obtained are 1-4031 and 1-4026. These 

 two values agree very favourably with the best determination of y 

 made by the Lummer-Pringsheim method.^ The average also agrees 

 very closely with the value calculated on the basis that air is a mix- 

 ture of -95% of a monatomic gas and 99-05% of a diatomic gas. 

 This calculated value the author finds to be 1-4029. The complete 

 results will be published later. 



1 Phys. Rev., Sev. 2, Vol. X, No. 5, p. 525, 1917. 



