Sir Jagadis Chunder Bose | Page 8

an accumulation of energy
by the plant. And with the accumulation of absorbed energy, a point is
reached when there is an overflow--the excess of energy bubbles over,
as it were, and shows itself in 'spontaneous' movements. The stimulus
being strong a single response--a single twitching of the leaflets--is not
enough to express the whole of the leaf's responsive energy and it
yields a multiple response--it reverberates--it manifests itself in
'automatic' pulsations. When, however, the accumulated energy is
exhausted, then there is also an end of 'spontaneous movements.' There
are strictly speaking, no 'spontaneous' movements; those known by that
name are really due either to the immediate effects of external stimulus
or to the stimulus previously absorbed and held latent in the plant to
find subsequent expression--due to the direct or indirect action of
external forces which are transformed in the machinery of the plants in
obedience to the principle of the Conservation of Energy.
"ASCENT OF SAP" "AND GROWTH"
Dr. Bose then showed that, not gross mechanical movements alone, but
also other invisible movements are initiated by the action of stimulus,
and that the various activities, such as the "ascent of sap" and "growth"
are in reality different reactions to the stimulating action of energy
supplied by the environment. In this way, Dr. Bose showed that several
obscure phenomena, in the life-processes of the plant, can be very
satisfactorily explained by the Mechanical Theory.
It would not be out of place to mention that Dr. Bose, to carry on his
researches on the Ascent of Sap, invented a new type of instrument
(Shoshungraph). And for an accurate investigation on the phenomenon
of growth of plants he devised an instrument (Growth Recorder) for
instantaneous measurement of the rate of growth and another

instrument (Balanced Crescograph) for determining the influences of
various agencies on growth. So very marvellous these instruments that
the growth, which takes place, during a few beats of pendulum, is
measured, and, in less than a quarter of an hour, the action of fertilizers,
foods, electrical currents and various stimulants are determined. "What
is the tale of Aladdin and his wonderful lamp" exclaims the Editor of
the Scientific American "compared with the true story told by the
crescograph?... Instead of waiting a whole season, perhaps years, to
discover whether or not it is wise to mix this or that fertilizer with the
soil one can now find in a few minutes!" Yet these are the instruments
which are better known in Washington than in Calcutta! The question
of their application to practical agriculture has excited more interest in
the United States of America than in this unfortunate land, which is an
essentially agricultural country!
FUNDAMENTAL IDENTITY OF REACTIONS
Dr. Bose showed that there is no physiological response given by the
most highly organised animal tissue that is not also to be met with in
the plant. He carried on "Researches on Diurnal Sleep" and showed that
the plant is not equally sensitive to an external stimulus during day and
night, and that there is a fundamental identity of life-reaction in plant
and animal, as seen in a similar periodic insensibility in both,
corresponding to what we call sleep. He also showed that the passage
of life in the plant, as in the animal, is marked by an unmistakable
spasm. He invented, an instrument (Morograph) with which he
recorded the critical point of death of a plant with great exactness. He
demonstrated, in the most conclusive manner, that there is an essential
unity of physiological effects of drugs on plant and animal tissues and
showed the modifications which are introduced into these effects by the
factor of individual 'constitution.' It may be mentioned casually that
"this physiological identity in the effect of drugs is regarded by leading
physicians as of great significance in the scientific advance of Medicine;
since we have a means of testing the effect of drugs under conditions
far simpler than those presented by the patient, far subtler too, as well
as more humane than those of experiments on animals."[19] Dr. Bose
further demonstrated that there is conduction of the excitatory impulse

in the plant, like the nervous impulse in the animal; and showed the
possibility of detecting the wave in transit and measured the speed with
which the excitation coursed through the plant and also showed that the
velocity of excitation is modified, by different agencies, even in the
case of ordinary plants. He also showed that the polar effects induced
by electric currents, both in plants and animals, are identical.
These remarkable researches on Plant Response have 'revolutionised in
some respects and very much extended in others our knowledge of the
response of plants to stimulus.'
FURTHER DIFFICULTIES
Dr. Bose communicated his paper 'On the Electric Pulsation
accompanying Automatic Movements in Desmodium Gyrans' to the
Linnaean