Part 19

SENSITIVE OR INSENSITIVE?

That not a "Mimosa" alone, but all plants are sensitive was demonstrated by some striking experiments. A spiral tendril, under electric shock was shown to writhe imitating the contortions of a tortured worm. In ordinary plants, all sides being equally sensitive contraction takes place on all directions with resulting neutral effect. Another striking experiment was to show how ordinary plants could be made sensitive by the mere process of amputation of the balancing half? Further experiments were shown demonstrating the effects of light, of warmth and other stimuli on the plant. Warmth worked antagonistically to light. The numerous permutations brought about by two changing variations were shown by a mechanical hand, which traced most complicated curves. In actual life the number of changing factors are very numerous, hence the intricacy involved in the manifestations of life.

The experiments that have been shown will help the audience to realise in some measure that the world we live in is not a theatre of caprice or chance, but that an all pervading law holds and regulates its destiny. We have seen that the vast expanse of life which is unvoiced, seemingly, so impassive, is instinct with sensibility. Thus the whole of the vegetable world, including rigid trees perceive the changes in their environment and respond to them by unmistakable signals. They thrill under light and become depressed by darkness; the warmth of summer and frost of winter, drought and rain, these and many other happenings leave a subtle impression on the life of the plant. By invention of apparatus of extreme delicacy, it is possible to make the plant itself write down the history of its own experience in a hieroglyphic which it is possible to decipher. From these pages, taken from the diary of the plant, it will perhaps be possible some day to get an insight into the great mystery that surrounds life itself. For I shall in the course of lectures given here show how the life of plants is a mere reflection of our own. I shall show how shocks and wounds affect them as they affect animals; how a common death-throb marks the crisis when life passes into death. The exuberance of life, on the other hand, will be shown by pulsing throbs of animal's heart and spontaneous beat in vegetal tissues. Another aspect of this exuberance will be shown in the imperceptible growth of plants. My recently invented Crescograph, to be exhibited at my lecture a fortnight hence, will magnify growth a million-fold and record ultra microscopic movements, smaller than a single wave length of light. By this apparatus growth will be instantaneously recorded and conditions which foster or inhibit growth discriminated. I shall demonstrate my discovery of the nervous system in plants, and show how shocks from without pass within, and how this nervous impulse modified during transit. It will further be shown how various stimulants, anesthetics and poison induce effects which are identical in man and in plant. It will be obvious how these studies will open new fields of inquiry in different branches of science; in Physiology and Psychology; in Medicine and in Agriculture.

--Amrita Bazar Patrika, 7-1-1918.

VISUALISATION OF GROWTH

Sir J. C. Bose delivered on the 18th January 1918, at the Bose Institute, the second of the series of discourses on revelations of plant life. This time the audience had the opportunity of witnessing the working of Bose's newly perfected Crescograph which is undoubtedly one of the marvels in modern Science. For this apparatus gives a visual demonstration of movements which are far beyond the highest powers of microscope. The invisible internal workings of life are thus for the first time revealed to man.

LAW VERSUS CAPRICE

The lecturer first described the infinite variations in life reactions in plants. The same external stimulus, he said apparently produces one effect in one plant; and precisely opposite in another. Some leaves move towards light; others are repelled by it. The root bends towards the centre of the earth, the shoot rises above away from it. Numerous other "tropic" movements are caused by contact, by electricity, by moisture and by invisible radiations. These effects appear so extremely diverse and capricious that some of the leading physiologists were forced to come to the conclusion that there was no law guiding such movement, but that the plant decides for itself what should be the effect of external conditions on it.

RECORD OF GROWTH

Most of these tropic movements are brought about by changes induced in growth by the action of different forces. But growth is so excessively slow that slight changes induced in it is impossible of detection. The proverbially slow paced snail moves two thousand times faster than the growing point of a plant. Hence to visualise growth and its changes, apparatus has to be invented which would magnify growth something like a million times. If such a thing were possible the pace of the snail would be quickened to the speed of a rifle bullet. The difficulties in connection with the devising and construction of apparatus with this extraordinary power appeared at first an impossibility. The Jewels for the fittings of the apparatus could not be found fine enough. The lecturer had to discard ordinary jewels for diamonds, such bearings being only made in Germany. But the outbreak of the war put an end to this source of supply. He had then to turn to resources available in India.

ADVANCE OF AGRICULTURE

The invention of method for immediate record of growth and its variations under various conditions is one of immense practical importance. Experiments on gigantic scales are in progress all over the world for this purpose. At Rothamstead, this work has been going on for more than half a century. The great Department of Agriculture in Mashington spends millions every year on such experiments, there being a thousand men employed in research. Recently many experiments have been undertaken on the effect of electricity on growth. The results obtained have been mostly contradictory. For real advance in agriculture we must first discover the laws of growth. Ordinary experiments on growth are of little value because they take weeks for detecting changes of growth which might have been brought about by charges in the environment. The only satisfactory method is to devise an apparatus which would make the plant itself record the rate of its growth, and the changes induced by food or treatment in the course of less than a minute, during which short time it is possible to maintain external conditions constant.

THE MAGNETIC CRESCOGRAPH

All the difficulties connected with the devising of apparatus has been completely removed by the lecturer's successful invention of his new magnetic crescograph in which practically unlimited magnification is obtained without the difficulties arising from the unavoidable friction of bearings. Magnetic forces are so exactly balanced that a disturbance in the balance caused by slightest movements such as that of growth is magnified ten millions of times. The application of this new principle will be of great importance in various investigations in Physics.

Sir J. C. Bose next demonstrated some marvellous results obtained with his apparatus. A seedling which on account of the Winter season appeared stationary jotted down by taps on a moving plate, the rate of its growth. The application of a chemical instantly arrested this growth, but an antidote timely applied, not only removed the torpor but enhanced the growth at an enormous rate. The life of the plant became pliant at the will of the experimenter, and nothing appeared more marvellous than the realisation that man has the power to pierce the veil that shrouds the mystery that had hitherto baffled him.

The lecturer explained how the effect of a given agent--a chemical solution or an electric current--is profoundly modified by the dose a given intensity, producing one effect and a different intensity giving rise to an effect diametrically opposite. This is the reason of the inexplicable anomalies which have baffled many investigators. Numerous are the forces which act on growth some helping, others retarding, the effects being further modified by the strength and duration of application. These factors that determine growth are each to be studied in detail, and the laws of effect of each to be discovered. There can be no real advance in scientific agriculture until this is done.

--Amrita Bazar Patrika, 19-1-1918.

SIR J. C. BOSE AT BOMBAY.

There was a brilliant gathering at the Royal Opera House on Tuesday the 22nd January 1918, when Sir Jagadis Bose gave a deeply interesting lecture on the history of the inception of his Institute in Calcutta and its aims together with an exposition of his scientific researches illustrated by lantern slides. The theatre was full long before the lecture commenced and several prominent people were present the bulk of the audience consisting of Indians.

Mr. Tilak in introducing the distinguished lecturer to the audience referred to Professor Bose's lasting services not only to the Indian nation but to the whole world. These references to Dr. Bose and his work elicited frequent applause from the large audience.

A FIFTY THOUSAND RUPEES LECTURE.

Sir Jagadis, who was accorded a most enthusiastic ovation on rising to address the gathering, acknowledged his gratitude to the public of Bombay who proved their appreciation of his work by their presence there that evening, and the fact that they had subscribed Rs. 50,000 for the occasion. He then gave a brief explanatory account of the nature and scope of his work, which he had planned and carried out alone for many years amidst many and varied difficulties. He gave an exposition by the aid of one of the delicate instruments of his own invention of how plants respond to various sounds and tunes and the beautiful colour display which was observed in this connection appeared as though he were a magician with a wand.

PLANTS UNDER ANAESTHETICS

The Doctor explained the meaning and significance of the thunderbolt which has been adopted as the symbol of the institution. He explained also the special uses to which the various parts of the buildings would be put. The fact was brought out that the entire building and grounds had been designed to suit the special needs of the Institute and care had been taken to make it as far as possible self contained. An interesting feature of the garden close to that portion which forms the residence of Sir Jagadis was the open platform perched above two trees, transplanted under anaesthetic conditions. A variety of apparatus is displayed under these trees and the platform is intended for observation or meditation or both. Dr. Bose here explained how trees when transplanted frequently died under the shock of the operation just as human being sometimes died, not from an operation but from the shock caused thereby. Similarly he had discovered and proved that trees could, like human beings, go through severe operations and survive the shock, if placed under the influence of an anaesthetic.

SOME PHENOMENA OF PLANT LIFE

The Professor explained next other experiments which he had performed on plants and whose results had exhibited the close parallel which plant life bears to human life. With the aid of another delicate instrument he showed how the growth of plants can be influenced by drugs and the demonstration on the screen of the manner in which the slow growth of a plant can be thus expedited was one of extraordinary interest. One was able to see the flame of life moving up the screen and recording at intervals the stages of growth, a lengthening of the intervals between each recorded glow illustrating the acceleration of growth as soon as the drug was applied. The instruments necessary to record this phenomenon are of extraordinary delicacy, and barely survived the strain of the journey from Calcutta.

ELECTRICITY AND AGRICULTURE

The last experiment was in regard to the effect of electricity on plant life. He referred particularly to the fact that it was his aim to discover the law of growth and atrophy among plants. Such a discovery had a great bearing on the future of agriculture and would revolutionise world thought. Electricity, he explained and illustrated, would promote or retard the growth of life by reaction. In England and other countries electricity had been applied to agriculture but without exact knowledge of its varying effect on plant life. He then showed by another apparatus of extreme delicacy that electricity might retard and even repel as well as promote the growth of plant life. But if the law of growth and decay could be ascertained, it was possible to regulate the control of life under most varied conditions.