In natural sequence to the investigations of the response in 'inorganic'
matter, has followed a prolonged study of the activities of plant-life
as compared with the corresponding functioning of animal life. But since
plants for the most part seem motionless and passive, and are indeed
limited in their range of movement, special apparatus of extreme
delicacy had to be invented, which should magnify the tremor of
excitation and also measure the perception period of a plant to a
thousandth part of a second. Ultra-microscopic movements were measured
and recorded; the length measured being often smaller than a fraction
of a single wave-length of light. The secret of plant life was thus for
the first time revealed by the autographs of the plant itself. This
evidence of the plant's own script removed the long-standing error which
divided the vegetable world into sensitive and insensitive. The
remarkable performance of the Praying Palm Tree of Faridpore, which
bows, as if to prostrate itself, every evening, is only one of the
latest instances which show that the supposed insensibility of plants
and still more of rigid tree is to be ascribed to wrong theory and
defective observation. My investigations show 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 caused by a
drifting cloud. This series of investigations has completely established
the fundamental identity of life-reactions in plant and animal, as seen
in a similar periodic insensibility in both, corresponding to what we
call sleep; as seen in the death-spasm, which takes place in the plant
as in the animal. This unity in organic life is also exhibited in that
spontaneous pulsation which in the animal is heart-beat; it appears in
the identical effects of stimulants, anaesthetics and of poisons in
vegetable and animal tissues. This physiological identity in the effect
of drugs is regarded by leading physicians as of great significance in
the scientific advance of Medicine; since here 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.
Growth of plants and its variations under different treatment is
instantly recorded by my Crescograph. Authorities expect this method of
investigation will advance practical agriculture; since for the first
time we are able to analyse and study separately the conditions which
modify the rate of growth. Experiments which would have taken months and
their results vitiated by unknown changes, can now be carried out in a
few minutes.
Returning to pure science, no phenomena in plant life are so extremely
varied or have yet been more incapable of generalisation than the
"tropic" movements, such as the twining of tendrils, the heliotropic
movements of some towards and of others away from light, and the
opposite geotropic movements of the root and shoot, in the direction of
gravitation or away from it. My latest investigations recently
communicated to the Royal Society have established a single fundamental
reaction which underlies all these effects so extremely diverse.
Finally, I may say a word of that other new and unexpected chapter which
is opening out from my demonstration of nervous impulse in plants. The
speed with which the nervous impulse courses through the plant has been
determined; its nervous excitability and the variation of that
excitability have likewise been measured. The nervous impulse in plant
and in man is found exalted or inhibited under identical conditions. We
may even follow this parallelism in what may seem extreme cases. A plant
carefully protected under glass from outside shocks, looks sleek and
flourishing; but its higher nervous function is then found to be
atrophied. But when a succession of blows is rained on this effect and
bloated specimen, the shocks themselves create nervous channels and
arouse anew the deteriorated nature. And is it not shocks of adversity,
and not cotton-wool protection, that evolve true manhood?
A question long perplexing physiologists and psychologists alike is that
concerned with the great mystery that underlies memory. But now through
certain experiments I have carried out, it is possible to trace "memory
impressions" backwards even in inorganic matter, such latent impressions
being capable of subsequent revival. Again the tone of our sensation is
determined by the intensity of nervous excitation that reaches the
central perceiving organ. It would theoretically be possible to change
the tone or quality of our sensation, if means could be discovered by
which the nervous impulse would become modified during transit.
Investigation on nervous impulse in plants has led to the discovery of
a controlling method, which was found equally effective in regard to the
nervous impulse in animal.
Thus the lines of physics, of physiology and of psychology converge and
meet. And here will assemble those who would seek oneness amidst the
manifold. Here it is that the genius of India should find its true
blossoming.
The thrill in matter, the throb of life, the pulse of growth, the
impulse coursing through the nerve and the resulting sensations, how
diverse are these and yet how unified! How strange it is that the tremor
of excitation in nervous matter should not merely be transmitted but
transmuted and reflected like the image on a mirror, from a different
plane of life, in sensation and in affection, in thought and in emotion.
Of these which is more real, the material body or the image which is
independent of it? Which of these is undecaying, and which of these is
beyond the reach of death?
It was a woman in the Vedic times, who when asked to take her choice of
the wealth that would be hers for the asking, inquired whether that
would win for her deathlessness. What would she do with it, if it did
not raise her above death? This has always been the cry of the soul of
India, not for addition of material bondage, but to work out through
struggle her self-chosen destiny and win immortality. Many a nation had
risen in the past and won the empire of the world. A few buried
fragments are all that remain as memorials of the great dynasties that
wielded the temporal power. There is, however, another element which
find its incarnation in matter, yet transcends its transmutation and
apparent destruction: that is the burning flame born of thought which
has been handed down through fleeting generations.
Not in matter, but in thought, not in possessions or even in attainments
but in ideals, are to be found the seed of immortality. Not through
material acquisition but in generous diffusion of ideas and ideals can
the true empire of humanity be established. Thus to Asoka to whom
belonged this vast empire, bounded by the inviolate seas, after he had
tried to ransom the world by giving away to the utmost, there came a
time when he had nothing more to give, except one half of an _Amlaki_
fruit. This was his last possession and anguished cry was that since he
had nothing more to give, let the half of the _Amlaki_ be accepted as
his final gift.
Asoka's emblem of the _Amlaki_ will be seen on the cornices of the
Institute, and towering above all is the symbol of the thunderbolt. It
was the Rishi Dadhichi, the pure and blameless, who offered his life
that the divine weapon, the thunderbolt, might be fashioned out of his
bones to smite evil and exalt righteousness. It is but half of the
_Amlaki_ that we can offer now. But the past shall be reborn in a yet
nobler future. We stand here to-day and resume work to-morrow so that by
the efforts of our lives and our unshaken faith in the future we may all
help to build the greater India yet to be.