Chapter 14

How then are we to know what unseen changes take place within the plant? The only conceivable way would be, if that were possible, to detect and measure the actual response of the organism to a definite testing blow. When an animal receives an external shock it may answer in various ways; If it has voice, by a cry, if dumb, by the movement of its limbs. The external shock is the stimulus, the answer of the organism is the response. If we can make it give some tangible response to a questioning shock, then we can judge the condition of the plant by the extent of the answer. In an excitable condition the feeblest stimulus will evoke an extraordinarily large response, in a depressed state even a strong stimulus evokes only a feeble response, and lastly, when death has overcome life, there is an abrupt end of the power to answer at all.

Prof. Bose then explained the principle and action of his apparatus by which the plant attached to it is automatically excited by successive stimuli which are absolutely constant. In answer to this the plant makes its own responsive records, goes through its own period of recovery, and embarks on the same cycle over again without assistance from the observer at any point. In this way the effect of changed external conditions is seen recorded in the script made by the plant itself.

It has been thought that plants like mimosa alone were sensitive. But Sir J. C. Bose's apparatus demonstrated the unsuspected fact that every plant and every organ of every plant answered to a shock by a contractile spasm, as by an animal muscle. If perception of feeble stimulus be taken as a measure of ascent in the scale of life then the superiority of man must be established on a foundation more secure than sensibility. The most sensitive organ by which we can detect electric current is our tongue. An average European can perceive a current as feeble as six micro-amperes, a micro-ampere being a millionth part of the electric unit. Possibly the tongue of a Celt is more excitable, and I have no doubt that my countrymen can easily boast the Celt in this particular test. But the plant mimosa is ten times more excitable than the tongue of an advocate in this province.

Professor Bose then showed how identical were the effects of light, warmth and various drugs on the plant and animal. These experiments bring the plant much nearer than we ever thought. We find that it is not a mere mass of vegetative growth, but that its every fibre is instinct with sensibility. We are able to record the throbbings of its pulsating life, and find these wax and wane according to the life conditions of the plant, and cease in the death of the organism. In these and many other ways the life reactions in plant and man are alike, and thus through the experience of the plant, it may be possible to alleviate the sufferings of man.

--_Amrita Bazar Patrika_, 9-2-1918.

CONTROL OF NERVOUS IMPULSE

At the first anniversary meeting of the Bose institute, held on the 30th November 1918, Sir J. C. Bose gave the following discourse on his recent discoveries relating to the question of control of nervous impulse, under the Presidency of His Excellency Lord Ronaldshay, Governor of Bengal.

It is one of the greatest of all mysteries how we are put in connection with the external world: how blows from without are felt within. Our organs of sensation are like so many antennae radiating in various directions and picking up messages of many kinds. All of these, when analysed to their utmost, consist of shock effects on different chords. An extremely feeble stimulus is below the limit of perception, a moderate stimulus transmits excitation, which is perceived as sensation of not an unpleasant character, but the tone of sensation becomes painful when the excitation is very intense. Our sensation is thus coloured by the intensity of the nervous excitation that reaches the central organ. We are subject to human limitations, through the imperfection of our senses on the one hand, and over-sensibility on the other. There are happenings which elude us because the impinging stimulus is too feeble to waken our senses; the external shock, on the other hand, may be so intense as to fill our life with pain.

Since we have no direct power over the shocks which come to us from the outside world, is it possible to control the nervous impulse so that it should be exalted in one case, and inhibited or obliterated in the other? Does advance of science hold any such possibility? This question is plainly fraught with high significance.

PROBLEM OF CONTROL OF NERVOUS IMPULSE

Before proceeding further it will be necessary first to obtain a clear idea of the function of a nervous tissue and its characteristics; secondly the manner, in which the nervous impulse is propagated; and lastly, we have to discover some compulsive force by which the impulse may be intensified or inhibited during transit. The nerve circuit may be liked to an electric circuit, and invisible impulse bringing about response in the indicator, be it the brain or the galvanometer. In the electric circuit the conducting power of the metallic wire is constant, and the intensity of the electric impulse depends on the intensity of the electric force applied. If the conducting power of the nerve were constant then the intensity of the nervous impulse and its resulting sensation would depend inevitably on the intensity of the shock from outside which starts the impulse. In that case the possibility of the modification of our sensation would be an impossibility. But there may be a likelihood that the power of conduction possessed by a nerve is not constant but capable of change. Should this surmise prove to be correct then we arrive at the momentous conclusion that sensation itself is modifiable, whatever the external stimulus. For the modification of nervous impulse there remains only one alternative; namely, some power to render the vehicle a very much better conductor or a non-conductor according to particular requirements. We require the nervous path to the supra-conducting to have the impulse due to feeble stimulus brought to sensory prominence. When the external blow is too violent we would block the painful impulse by rendering the nerve a non-conductor.

Under narcotic the nerve becomes paralysed and we can by its use save ourselves from pain. But such heroic measures are to be resorted to in extreme cases, as when we are under the surgeon's knife. In actual life we are confronted with unpleasantness without notice. A telephone subscriber has an evident advantage, for he can switch off the connection when the message begins to be unpleasant. Statesmen or politicians have been known to cultivate convenient deafness; but that is a mere pretence. The unpleasant things heard, would still continue to rankle. It is not every one that has the courage of Mr. Herbert Spencer who openly resorted to his ear plugs whenever his visitor became tedious.

The lecturer then explained that the propagation of nervous impulse is a phenomenon of transmission of molecular disturbance. It occurred to him that the transmission could be controlled if he succeeded in discovering a compulsive force which would confer on the conducting particles two opposite molecular dispositions, one of which would exalt and the other resist the impulse. His experiments were first conducted with the primitive type of nerve which he had previously discovered in plants. In full confirmation of his theory, he succeeded in conferring on the nervous tissue two opposite dispositions. Under favourable disposition the nerve is rendered supra-conducting; subliminal stimulus now becomes fully perceived. Under the opposite molecular disposition the violent impulse due to excessive stimulus becomes weakened or arrested during transit, and the plant remains quite unaffected by the external shock.

The lecturer has in his previous works demonstrated the unity of life-reactions in the plant and animal. A climax is now reached when by the application of identical treatment he is able to confer alternately on the same animal nerve, supra-conducting or non-conducting property at will. Under a particular molecular disposition the experimental frog perceived and responded to stimulus which had hitherto been below its threshold of perception. Under the opposite disposition violent tetanic spasm caused by the irritant salt applied to the nerve became at once quelled. The normal property of the nerve was at once restored on the withdrawal of the predisposing force.

MAN VICTORIOUS OVER CIRCUMSTANCE

Thus by the control of molecular disposition of the conducting nerve, nervous impulse, and the resulting sensation may become profoundly modified. The external is not so overwhelmingly dominant, and man is not to be merely passive in the hands of destiny. There is a latent power which would raise him above the terrors of his inimical surroundings. It remains with him that the channels through which the outside world reach him should, at his command be widened or become closed. It may thus be possible for him to catch those indistinct messages that had hitherto eluded him or he may withdraw within himself, so that in his inner realm, the jarring notes and the din of the world should no longer affect him.

The whole audience heard the discourse with spell bound interest. The Indian Scientist came to that realisation by experiments at which the Indian Jogis of yore arrived by intuition. Following an absolutely original line inventing his own apparatus of the most simple yet subtle delicacy and having constructed them by the hands of Indian artisans, working without collaborators and with the smallest modicum of recognition by his fellow scientists, he has pursued his investigation to a result which has been a revelation to the whole world. Dr. Bose has proved that man and plant are one body and life in their physiology, in their vital habits and nervous responses. He has clearly demonstrated that nervous life in the plant responds to the same stimuli as in human beings. He has established between animal and plant a unity of incipient mind. The plant not only lives and dies, wakes and sleeps but it makes the responses which in animal would be pleasure and pain.

Dr. Bose has made a great step towards the unification of knowledge. A bridge has been built between man and inert matter. Even if we take Dr. Bose's experiments with metals in conjunctions with his experiments on plants, we may hold it to be practically proved for the thinker that Life in various degrees of manifestation and organisation is omnipresent in Matter and is no foreign introduction or accidental development, but was always that to be evolved.

The ancient thinkers knew well that life and mind exist everywhere in essence and vary only by the degree and manner of their emergencies and functionings. All is in all and it is out of complete involution that the complete evolution progressively appears. It is only appropriate that for a descendant of the race of ancient thinkers who formulated that knowledge, should be reserved the privilege of initiating one of the most important among the many discoveries by which experimental science is confirming the wisdom of his forefathers.

--_Amrita Bazar Patrika_, 4-12-1918.

MARVELS OF GROWTH AS REVEALED BY THE "MAGNETIC CRESCOGRAPH"

[Sir J. C. Bose has recently invented the "Magnetic" crescograph. It is a supersensitive instrument and the very high magnification obtained by it surpasses all existing appliances. By this instrument, phenomena hitherto beyond the reach of investigation can now be studied with great precision. It shows ultra-microscopic changes inducted in a growing organism even by a puff of smoke or a gentle breeze, by a passing cloud or fleeting brightness. This super magnifier was exhibited for the first time by Sir J. C. Bose before an appreciative gathering 10-1-1919. A number of lady students, professors, lawyers, doctors and several eminent personages gathered to hear the great Indian scientist.]

In his Discourse on the above subject on Friday, Sir J. C. Bose illustrated how the limitations imposed on the advance of science by the imperfection of our senses, may stimulate the invention of supersensitive apparatus which reveals to us the existence of phenomena hitherto unknown. Thus the invention of the microscope from a simple lens magnifying 3 or 4 times into progress up to 1500 diameters has given birth to new sciences. But still higher magnification is demanded in unravelling the mystery of movements associated with the simplest type of life as seen in plants. Greatest potentiality in life is often latent; the gigantic banian tree grows out of a thing which is smaller than the mustard seed. Within the seed-coat the dormant life remains in safety, protected from dangers outside. The seeds may thus be subjected without harm to cold so intense as will freeze mercury into solid and air into liquid. Winds and hurricanes scatter the seed of life and the cocoa-nut rides the tumultuous waves till anchored safe in an island yet to be inhabited. In due season there begins a series of most astonishing transformations; the latent life wakens, and the seedling begins to grow. The root turns downwards and the shoot upwards. Underground, the root winds its way round stones and obstacles towards moist places. Above ground the stem bends as if in search of light. Tendrils twine about a support. These visible movements are striking enough, but within the unruffled exterior of the plant body there are others, energetic and incessant, which escape our scrutiny. The bending of a growing organ towards or away from stimulus must be due to unequal growth on two sides of the organ, a retardation of growth on the proximal or acceleration on the distant sides. Various theories have been advanced which have proved inadequate. For the identical stimulus of gravity produces one kind of curvature in the root and the very opposite in the shoot. The possibility of direct experimental investigation has been frustrated by the excessive slow rate of growth rendering accurate measurement impossible.

THE SLOWNESS OF GROWTH

The movement of growth is two thousand times less rapid than the place of the proverbially slow-footed snail. Taking the average annual growth in height of a tree to be 5 ft., it will take a tree a thousand years to cover a distance of a mile. We take a piece of 2 ft. in the course of half a second, during the interval plant grows through a length of 1,100,000 part of an inch or half the length of a wave of light. For investigation on the effect of external conditions on growth we have to measure even a fraction of that excessively small length.

The peasant has eagerly watched the growth of his plants on which his own life and the world's depend and, even realised something of its vicissitudes, so the vegetable physiologist has here one of the many problems of his science. The invention of growth-measuring instruments has thus been one of his main endeavours. He has hitherto succeeded by the use of levers with unequal arms to obtain a magnification of about 20 times, and even then it takes many hours for growth to become perceptible; owing to the practical impossibility of maintaining the external conditions constant for so many hours, the results of measurement of growth become vitiated. It is therefore necessary to produce a magnification so high that growth should become measurable in less than a minute. The first improvement effected by the lecturer, now some fourteen years ago, was his Optical Lever, which at once raised the magnification from 20 to 1000 times, an advance which at the time seemed to many incredible, but it is at length coming into use in advanced laboratories in Europe.

THE RECORDING CRESCOGRAPH

A new apparatus devised by the lecturer, the Recording Crescograph, is described in the Transactions of the Royal Society, and of the Bose Institute. By a compound system of levers the magnification is raised to 10,000 but this is not without great technical difficulties, which cost five years of efforts to overcome. Thus the levers require to be extremely light; this was secured by the use of an alloy of aluminium used in the construction of Zeppelins: this combines lightness with rigidity. Another difficulty almost unsuperable arises from the friction at the bearings of the fulcrum, the best watch jewels made of ruby were employed, but the supply was cut off from Germany by the war. This proved a blessing in disguise, for it forced the lecturer to devise a new principle of suspension using local material. This was found in practice to be far superior to jewel bearings, which became clogged by invisible dust particles present in the air. With this Recording Crescograph many phenomena of extreme interest have been discovered. The plant itself not only recorded its normal rate of growth but the slightest change induced in it by the action of different forces. So delicate was the apparatus that it analysed growth into a series of pulses, a sudden shooting out followed by a partial recoil. It showed how the growth of the plant was retarded by a mere touch, and the time it took the plant to recover from the effect of contact, and all these in course of a few seconds. The effect of different food on growth, the effect of different drugs, or living capacity these and many more became revealed by the automatic record made by the plant. This has opened out fresh and more exact method of medical inquiry, and of practical agriculture.

THE MAGNETIC CRESCOGRAPH

Such unlooked for results called for yet higher magnification, and at first it seemed that further multiplying lever might be added to the previous system. But this failed on account of added mass and friction; and some altogether new solution had therefore to be sought. Material contact having proved unworkable the ideal weightless and frictionless linking was obtained by introducing a new magnetic contrivance, and this with the surprising potency of magnification from 5 to 100 million times. The mind cannot grasp the meaning of this stupendous magnification; how then could we translate it in terms which may be understood? Let us take once more our slow-footed snail, a magnification of ten million times would convert its speed to something for which there is no parallel even in modern gunnery practice. The 15 inch cannon of the "Queen Elizabeth" has a muzzle velocity of 2360 ft. per second or 8-1/2 million feet per hour. But the speed of the snail when magnified ten million times would render it 200 million ft. per hour or 24 times faster than the fastest cannon shot. We may next turn to the cosmic movement for a parallel: A point in equator whirls round at the rate of 1037 miles per hour. But a snail with the magnified speed would beat the earth by going round 40 times during the period the earth makes but one revolution!

LIFE IN STATE OF SUSPENSE AND ITS SUBSEQUENT RESOLUTION

With the experiments carried with the Magnetic Crescograph life becomes subservient to the will of the experimenter. The rate of growth is indicated by the speed with which a spot of indicating light moves across the scale. The actual rate of growth is fifty thousandth part of an inch per second; this under magnification is seen by the indicating spot of light to move at the rate of 36 inches per second: this is the normal rate. The plant is made to imbibe soda water and the growth becomes suddenly exalted some ten times; but a puff of tobacco smoke instantly retards the rate. To induce further retardation a depressing drug is next applied. The growth gradually comes to a stop and the quiescent of the spot of light shows life in a state of suspense. The plant is now hovering in an unstable poise between life and death, a slight tilt one way, and life gets interlocked in the rigidity of death. But the antidote is applied just in time, the torpor and suspense is over, and life renews her activity once more with the fullest vigour.

It is true that man is but poorly provided for his voyage of discovery in seas unknown, he can hear little and see less. A single octave of light circumscribes his vision; even of the visible the size of the ripple of light imposes an impassable barrier. But he has not been deterred by his limitations but has on the contrary been spurred on its greater efforts in his explanation of the invisible. The mysterious movements of life are not to remain for him inscrutable and indecipherable for all times: but his untiring and single-minded pursuit will someday reveal to him the secret that lies behind the manifestations of life.

--_Amrita Bazar Patrika_, 13-1-1919.

THE NIGHT-WATCH OF NYMPHAEA

Sir J. C. Bose gave the following Discourse on the 'Night-Watch of Nymphaea,' at the Bose Institute, on the 24th January, 1919.

[Sir J. C. Bose's discourse delivered at the Bose Institute, on the 24th January, 1919, dealt with the mysterious phenomenon of recurrent opening and closure of flowers. Some of them open in the morning and close in the evening; others do exactly the opposite opening at night and closing during the day. These various effects have been described as the 'waking' and 'sleep' movements of plants. The subject had attracted the attention of plant physiologists for more than half a century. After summarising the various results lost in his recent work says that no satisfactory explanation of the sleep movements of plants has yet been forthcoming and that the true theory can only be established after new and exhaustive research. This investigation has been in progress at Sir J. C. Bose's laboratory for the last five years; and special automatic recorders have been invented by means of which numerous plants have been recording their movements for every hour of the day and night and for many days in succession.]

In course of his discourse the lecturer said "The poets have forestalled the men of science. Why does the water-lily 'Kumud or Nymphaea' keep awake all night long and close her petals during the day? Because the water-lily is the lover of the Moon and like the human soul expanding at the touch of the beloved, the lily opens out her heart at the touch of the moon beam, and keeps watch all night long; she shrinks affrighted by the rude touch of the Sun, and closes her petals during the day. The outer floral leaves of the lily are green, and in the day time the closed flowers are hardly distinguishable from the broad green leaves which float on the water. The scene is transformed in the evening as if by magic, and myriads of glistening white flowers cover the dark water.

"The recurrent daily phenomenon has not only been observed by the poets, but an explanation offered for it. It is the moonlight then that causes the opening of the lily, and the sunlight the movement of closure. Had the poet taken out a lantern in a dark night; he would have noticed that the lily opened at night in total absence of the moon; but a poet is not expected to carry a lantern and peep out in the dark; that inordinate curiosity is characteristic only of the man of science. Again the lily does not close with the appearance of the sun; for the flower often remains awake up to eleven in the forenoon. A French dictionary maker saw Cuvier, the Zoologist about the definition of the crab as 'a little red fish which walks backwards.' 'Admirable,' said Cuvier. 'But the crab is not necessarily little, nor is it red till boiled; it is not a fish, and it cannot walk backwards. But with these exceptions your definition is perfect.' And so also with the poet's description of the movement of the lily, which does not open to moonlight, nor yet close to the sun."

THE 'SLEEP' AND 'WAKING' OF JHINGA FLOWER