under Various Electrical Conditions . 139 
This does not mean that an acceleration process, if present, is inexpli- 
cable. It may well be that one result of electrification may be increased 
transpiration ; this alone would account for a more rapid attainment of 
maturity by the plant. The effect of such electrical conditions upon trans- 
piration is now being investigated by the biophysicists of the Department of 
Agriculture in Washington. 
The effect of electrical discharge upon the important anabolic processes 
of the plant is at present being further investigated, but it may be pointed 
out that an increased activity of constructive metabolism has been previously 
reported by Pollacci, Koltonski, Berthelot, and others. 
This work, which has been in progress for several years, has been made 
possible only through various research grants that have been made from 
time to time. The work was started at Bristol as the result of a grant 
from the Colston Research Fund of the University of Bristol, and it has 
been possible to continue the investigation in the Botanical Department of 
the University of Leeds, owing to grants received from the special Research 
Fund placed at the disposal of the Board of Agriculture by the Development 
Commissioners. 
During the progress of the work we have been led into fields very 
remote from the ordinary path of the botanist, and we have to acknowledge 
with gratitude the great help received from colleagues in other scientific 
departments ; especially have we to thank Dr. A. M. Tyndall, of the Physics 
Department, University of Bristol, and the staff of the Physics Department 
of the University of Leeds for continuous kindness and advice. 
Experimental. 
In the experimental investigation of the influence of electricity upon 
the carbon dioxide output, it was considered advisable to employ germinating 
seeds and young seedlings kept in the dark, so that the reverse process of 
photosynthesis was eliminated. 
The methods of electrification were similar to those which have been 
tried in the field experiments, and they may be conveniently discussed 
under two heads, viz. : 
1. Experiments with small direct currents at a relatively low voltage. 
2 . Experiments with electric discharge at high tensions. 
Before giving an account of the methods of applying these electrical 
conditions, it will be advisable to describe the apparatus used in the deter- 
mination of the carbon dioxide output, after which the alterations necessi- 
tated by different methods of electrification can be easily indicated. 
The respiration was quantitatively determined by a volumetric method, 
the amount of carbon dioxide being calculated in grammes. The method was 
the same in all experiments, and was essentially that advocated by Detmer. 1 
1 Practical Plant Physiology, Eng. ed., 1898, p. 264. 
