Sir Jagadis Chunder Bose | Page 7

Photographic Society to
give a discourse 'On the Strain Theory Vision and of Photographic
Action,' which was published by the Society, in its Journal, in June
1902. He then wrote a paper 'On the Electric Response in Animal,
Vegetable and Metal,' which was read before the Belfast meeting of the
British Association, in 1902. The President of the Botanical Section at
Belfast, in his address, observed "Some very striking results were
published by Bose on Electric Response in ordinary plants. Bose's
investigations established a very close similarity in behaviour between
the vegetable and the animal. Summation effects were observed and
fatigue effect demonstrated, while it was definitely shown that the
responses were physiological. They ceased as soon as the piece of
tissue was killed by heating. These observations strengthen
considerably the view of the identical nature of the animal and
vegetable protoplasm."
Dr. Bose then brought out a systematic treatise embodying the results
of his researches under the significant title of 'Response in the Living

and Non-living.' He returned to India, in October, 1902.
GOVERNMENT RECOGNITION
After he had come back, from the Second Scientific Deputation, the
Government of India conferred on him the distinction of Companion of
the Order of the Indian Empire, in 1903, in recognition of his valuable
researches.
PLANT LIFE AND ANIMAL LIFE
Next Dr. Bose, in natural sequence to the investigation of the response
in 'inorganic' matter commenced 'a prolonged study of the activities of
plant life as compared with corresponding functioning of animal life.'
ALL PLANTS ARE "SENSITIVE"
It was believed that so-called 'sensitive' plants alone exhibited
excitation by electric response. But Dr. Bose, believing in continuity of
responsive phenomena, used the same experimental devices, with
which he had already succeeded in obtaining the electric response of
inorganic substances, to test whether ordinary plants also--meaning
those usually regarded as 'insensitive'--would or would not exhibit
excitatory electrical response to stimulus. With the help of very
delicate instruments, Dr. Bose demonstrated the very startling fact that
not only every plant, but every organ of every plant gave true excitatory
electric response--and that response was not confined alone to
'sensitive' plants like Mimosa.
Dr. Bose then proceeded to investigate whether the responsive effects
which he had shown to occur in ordinary plants might not be further
exhibited by means of visible mechanical response, thus fully removing
the distinction commonly assumed to exist between the 'sensitive' and
supposed 'non-sensitive.' Dr. Bose invented 'special apparatus of
extreme delicacy,' which detected infinitesimal tremors, and showed
that ordinary plants, usually regarded as insensitive, gave motile
responses, which had hitherto passed unnoticed. His later investigation
shows that "all plants, even the trees, are fully alive to changes of

environment; they respond visibly to all stimuli, even to the slight
fluctuations of light by a drifting cloud."[17]
'TROPIC' MOVEMENTS
Finding that the plants give, not only electric but motile response as
well, to stimulus, Dr. Bose proceeded to study the nature of responses
evoked in plants by the stimuli of the natural forces. He found that
plants respond visibly, by movements, to environmental stimuli. But
the movements induced--'tropic' movements--are extremely diverse.
Light, for example, induces sometimes positive curvature, sometimes
negative. Gravitation, again, induces one movement in the root, and the
opposition in the shoot. Dr. Bose applied himself to find out whether
the movements in response to external stimuli, though apparently so
diverse, could not be ultimately reduced to a fundamental unity of
reaction. As a result of a very deep and penetrating study of the effects
of various environmental stimuli, on different plant organs, he showed
that the cells on two sides are unequally influenced, on account of
different external conditions, and contract unequally, and hence the
various movements are produced--that the many anomalous effects,
hitherto ascribed to 'specific sensibilities,' are due to the 'differential
sensibilities'--differential excitability of anisotropic structures and to
the opposite effects of external and internal stimuli--that all varieties of
plant movements are capable of a consistent mechanical explanation.
Dr. Bose's "latest investigations recently communicated to the Royal
Society have established the single fundamental reaction which
underlies all these effects so extremely diverse."[18]
EXTENDED APPLICATION OF MECHANICAL THEORY
With an extended application of his mechanical theory, Dr. Bose has
gradually removed the veil of obscurity from many a phenomenon in
plant life. The 'autonomous' movements of plants, for example, which
remained enveloped in mystery, received a satisfactory solution at his
hands.
'AUTONOMOUS' MOVEMENTS

It was believed that automatically pulsating tissues draw their energy
from a mysterious "vital force" working within. By controlling external
forces, Dr. Bose stopped the pulsation and re-started it and thus
demonstrated that the 'automatic action' was not due to any internal
vital force. He pointed out that the external stimulus--instead of causing,
as was customary to suppose, an explosive chemical change and an
inevitable run-down of energy--brings about