ELECTRICAL ENERGY 41 



tricity through a solution of carbon dioxide in water. Fenton * 

 also has pointed out that the synthetic action of light and of 

 the silent electrical discharge are practically identical. Thus 

 there is evidence which suggests that electric energy may play 

 a part in the earlier processes of photosynthesis ; a suggestion 

 which is supported by the fact that, according to Polacci,f 

 the formation of carbohydrates is promoted in leaves by 

 electrical energy, provided it be not too intense, especially 

 when a continuous current is made to pass directly into the 

 tissues. 



As a result of a number of experiments, Gibson J comes to 

 the conclusion that the light rays which are absorbed by the 

 chlorophyll are transformed into electrical energy, and it is 

 this transformed energy which brings about the decomposition 

 of carbonic acid to formaldehyde and oxygen. This opinion 

 is based on evidence the details of which apparently have not 

 been published. 



Waller § and others have made many observations on the 

 photo-electric responses of plants, but much further investi- 

 gation is necessary before the correlation of these phenomena 

 with the photosynthetic process is possible. Attention may 

 also be drawn to the work of Kernbaum,|] who found that water 

 exposed to the influence of jS-rays and of ultra-violet rays led 

 to the production of hydrogen and hydrogen peroxide. Usher 

 and Priestley also found that an aqueous solution of carbon 

 dioxide could be decomposed by the a and j8-rays from radium 

 emanation. The action of -oooi c.c. of radium emanation on 

 200 c.c. of water saturated with carbon dioxide resulted in 

 four weeks in the production of hydrogen peroxide and for- 

 maldehyde. Most of the latter was in a polymerized state, 

 but the solution contained no sugar. 



The effect of salts of radio-active metals such as potassium 

 and rubidium has been the subject of many investigations 

 but it is impossible as yet to draw any definite conclusions. 



* Fenton : " Journ. Chem. Soc," 1907, 91, 687. 



t Polacci : " Atti. Inst. Bot.," Pavia, 1905, II., H, 7. 



I Gibson : " Ann. Bot.," 1908, 22, 117. 



§ Waller : id., 1925, 39, 5*5- 



|| Kernbaum : " Compt. rend.," 1909, >4 8 » 755, >49» 273. 



