TESTING IN VACUO 115 



As regards the occasional reversals of polarity observed 

 by Dr. Waller and other writers it is, I think, only necessary 

 to remark that the phenomenon is common enough when 

 there is electrostatic capacity in the circuit and should 

 sufficiently explain " blaze-currents " as being nothing more 

 than a manifestation of purely physical phenomena. 



At the time these tests were taken I was using a garden 

 " earth." This will explain the negative variation which 

 sometimes followed upon the fall to zero. And I should like 

 to make it clear that such fall does not imply more than 

 temporary exhaustion — suspended animation — ; between 

 which and electrical death there is a wide difference. Life 

 in a seed or a plant — in an electro-physiological sense — is 

 dependent upon the retention of its electrostatic capacity 

 and this in turn depends upon the preservation of its internal 

 secretion. If it is quite dry the seed or the plant quickly 

 becomes moribund and soon dies if not supplied with 

 moisture. After the nucellus of the seed or the conducting 

 substance of the plant became fibroid, the first will not 

 germinate or the second recover. 



