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SMITH : 



On going out to Ceylon in 1905, the pijesent writer took a 

 supply of thermo-electric junctions similar to those used by 

 Blackman and Matthaei (3). By means of these and a gal- 

 vanometer and using substantially the method described by 

 Blackman and Matthsei (3), the following investigation into 

 the temperatures of leaves in tropical insolation was carried 

 out. It seemed likely that on a subject so far so little investi- 

 gated, results of interest and importance might follow from 

 a more extensive study of the facts in the quite different 

 environment afforded by the tropical climate of Ceylon. 



Description of Apparatus. 

 The apparatus used differed in some slight respects from 

 that described by Blackman and Matthsei (3). 



At Dr. Blackman's suggestion, the wooden frame in which 

 his experimental leaves were fastened was abandoned. The 

 wooden base of this frame was close beneath the leaf, and when 



