THE EFFECT OF ELECTRICITY UPON PLANTS. 
193 
supports. Bertholon states that the use of this apparatus was 
invariably accompanied with an improvement in the appearance of the 
vegetation and with an increase in the fertility of the plants, etc. 
Grandeau^ (1879) attempted to demonstrate the importance of 
atmospheric electricity by showing that when the plant was protected 
by means of a wire cage its development was greatly retarded. 
In Grandeau’s work, and in that of his pupil, Leclerc, the com- 
parisons between the protected and control plants were not merely 
qualitative, but measurements of size, of gain in weight, and quantita- 
tive analysis of the plants were made. In this way they satisfied 
themselves that leaf and stem development was considerably retarded 
by the protection with a metallic network. 
On the other hand Ch. Naudin, about the same time, published 
experiments carried out in the same manner, in which the plants left 
exposed to the open air had not grown so well as the ones protected 
beneath a wire cage. 
The application of atmospheric electricity to stimulate plant growth 
has been a fairly common practice in France since Bertholon’s time, 
some modification of what is termed the Geomagnetifm-e system being 
adopted. 
A lightning conductor is raised in an exposed position to collect 
atmospheric electricity, and this is connected with wires running 
through the earth under the plants it is desired to stimulate. With 
this method good results are claimed, though Lord Kelvin’s suggestion 
is perhaps worthy of note, viz., that possibly the value of the treatment 
lies in the upturning of the earth necessary to plant the wire. 
M. Pinot de Moira has used the system for several years in his 
garden in Clifton, always with favourable results ; he has also shown 
me rows of peas planted beneath a wire cage which were far less 
advanced than the control rows outside the cage. 
Recently a great deal of work has been carried on in France, at the 
station for Agricultural Chemistry established at Meudon, by Professor 
Berthelot,^ who has tried the effect of the silent discharge, and par- 
ticularly of atmospheric electricity upon plants. 
He compared the growth of plants at the top of a 28 metre tower 
with that of plants growing at the foot, and considered that greater 
growth at the higher level was largely due to the potential gradient in 
the atmosphere. His explanation of the action of the current is 
mentioned later. 
Electricity has been applied in a different way by Barrat in France, 
and Speschnew in Russia. In their experiments metal plates were 
sunk in the ground with a current passing through the soil between 
them, and apparently this stimulated the plants in this part of the soil 
to more vigorous growth than the plants on either side in the control 
plots. 
^ Grandeau. Chimie et Physiologie appliquees a I’Agriculture et la Sylvicul- 
ture. — Berger, Levrault, et Cie, Paris. 
2 Berthelot. Chimie Vegetale et Agricole. T. I. 
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