Zhc i£ffect of jElcctiicit^ upon plants. 
By J. H. Priestley, B.Sc. 
D uring the last two years several attempts have been made in 
this locality to apply electricity as a stimulus to plant growth ; in 
some cases these experiments have been upon an unusually large scale, 
and, as the subject is clearly one of great importance, it has been 
thought advisable to place the results upon record, and at the same 
time to give an account of further experimental work recently carried 
out in the Botanical Garden and Laboratories at the College. It is 
also intended to discuss some suggested explanations of the physio- 
logical action of the current. 
The experiments upon a large scale which are to be described have 
all been the work of Mr. J. E. Newman, who has carried them out at 
Bitton, near Bristol, and at Gloucester, in 1905, and at Bevington 
Hall, near Evesham, during 1906. 
I am much indebted to Mr. Newman for keeping me so closely in 
touch with his work, and for allowing me to embody his results in 
this paper. 
The earliest work upon this subject with which I am 
Historical, acquainted is that of the Scotch physician, Mambray, in 
Edinburgh, and apparently about the same time Jallabert, 
in Geneva, carried out experiments upon the subject. 
The success that they met with apparently caused the Abbe NolleG 
to take up the subject in 1749. His experiments consisted in suspend- 
ing iron plates upon steel chains hanging from a dry silk cord. 
Upon these insulated metal plates he kept animals and plants, the 
whole series of trays being charged from a somewhat cumbrous influence 
machine requiring the continuous efforts of three men to drive ; he 
found that maize and mustard thus electrified germinated in every 
case more rapidly than control plants. 
The Abbe Bertholon^ (1783) greatly enhanced the practical interest 
of the subject by suggesting that atmospheric electricity was an im- 
portant factor in the environment of the plant. He applied his idea 
practically by constructing various types of an apparatus he called the 
electro-vegetometre. 
This consisted of a head of metallic points raised in the air in the 
manner of a lightning conductor and connected by a flexible conductor 
to a moveable iron bar terminating in a series of discharge points just 
over the plants to be electrified. 
Atmospheric electricity is then collected by the upper end of the 
structure and discharged on to the plants from the lower end, the 
whole of the conducting structure being insulated by suitable wood 
^ Abbe Nollet. Researches sur les causes particulieres des plienomenes 
electriques. Freres Guerin, Paris. 
Abbe Bertholon. De rElectricite des vegetaux. — Bidot Jeune, Paris. 
