832 



BIOPHYSICAL PHENOMENA 



[PT. Ill 



Not a few researches have been made in which the effect of elec- 

 trical energy applied in various ways has been tested as a stimulus 

 for embryonic growth or differentiation. The results have been uni- 

 formly negative, except from a teratological point of view, and even 

 then very little illumination has resulted from such experiments. In 

 1840 Rusconi initiated this type of work by exposing hen's eggs to 

 the action of an electrical current, constantly flowing, but his results 

 were quite negative. Fasola in 1887 and Roux in 1889 both found 

 nothing but a few malformations, which any treatment might have 

 produced. In the last decade of the last century, there were several 



30 mins. 



Fig. 205. 



papers on this subject; thus Windle stated that a shght retardation 

 of growth was noticeable when the embryo was subjected to a con- 

 tinually flowing electric current, but that incubation in a strong 

 magnetic field was favourable. His experiments were not done 

 statistically. Dareste obtained teratological effects, but was con- 

 tradicted by PieralHni, and Rossi stated that development was un- 

 doubtedly modified by electric currents, but probably only indirectly 

 on account of interference with other factors. The only recent in- 

 vestigations of the matter are those of Gianferrari & Pugno- Vanoni, 

 who in 1923 reported the results of subjecting salmon eggs to high 

 frequency currents during their development. Duplications and 

 various terata were produced. On the whole, this seems to be 



