440 



Sir James Dewar on Cloudland Studies [Jan. 2*, 



and the pressures observed, with and without the light excitation, 

 are set ont in the following tables ; and the manner of the rise and 

 fall of pressure with time is shown in Fig. 22. The increments of 

 pressure, though small, are obviously sufficient to cause some loss of 

 efficiency of charcoal-vacuum apparatus subjected to strong light. 



Acknowledgment is due to Mr. W. J. Green, B.Sc, for the 

 valuable assistance he rendered in the laboratory and in the prepara- 

 tion of this account of the work. 



December, 1923. 



WEEKLY EVENING MEETING, 

 Friday, January 21, 1921. 



The Hon. Sir Charles Parsons, K.C.B. LL.l). F.R.S, 



Vice-President, in the Chair. 



Sir Frank Benson. 

 Shakespeare and Democracy. 



[No Abstract.] 



