Part 9

In the matter of these so-called spontaneous activities of the plant, I find that there are two distinct types. In one, the overflow is initiated with very little storage, but here the unusual display of activity soon comes to a stop. To maintain such specimens in the rhythmic condition, constant stimulation from outside is necessary. Plants of this type are extremely dependent on outside influences, and when such sources of stimulus are removed, they speedily come to an inglorious stop. Kamranga or Averrhoa is an example of this kind. In the second type of automatic plant activity I find that long continued storage is required, before an overflow can begin. But in this case, the spontaneous outburst is persistent and of long duration, even when the plant is deprived of any immediately exciting cause. These, therefore, are not so obviously dependent as the others on the sunshine of the world. Our telegraph-plant, Desmodium or Bon charal, is an example of this.

It appears to me that we have here a suggestive parallel to certain phenomena with which this audience will surely prove more familiar than I, namely, the facts of literary inspiration. For the attainment of this exalted condition, also, is it not necessary to have previous storage, with a consequent bubbling overflow? Certain indications incline me to suspect that perhaps in this also we have an example of so-called spontaneity, or automatic responsiveness. If this be so, aspirants, to the condition might well be asked to decide in whose footsteps they will choose to tread--those of Kamranga, with its dependence on outside influences, and inevitably ephemeral activity, or those of Bon charal, with its characteristic of patient long enduring accumulation of forces, to find uninterrupted and sustained expression.

THE PLANT'S RESPONSE TO THE SHOCK OF DEATH

A time comes when, after one answer to a supreme shock, there is a sudden end of the plant's power to give any response. This supreme shock is the shock of death. Even in this crisis, there is no immediate change in the placid appearance of the plant. Drooping and withering are events that occur long after death itself. How does the plant then, give this last answer? In man, at the critical moment, a spasm passes through the whole body, and similarly in the plant, I find that a great contractile spasm takes place. This is accompanied by an electrical spasm also. In the script of the Morograph, or Death recorder, the line that up to this point was being drawn, becomes suddenly reversed, and then ends. This is the last answer of the plant.

These are mute companions, silently, growing beside our door, have now told us the tale of their life-tremulousness and their death spasm, in script that is as inarticulate as they. May it not be said that this their story has a pathos of its own, beyond any that the poets have conceived?

PROF. J. C. BOSE AT MAYAVATI

MARVELS OF PLANT LIFE

On the 8th June 1912, Dr J. C. Bose, who had gone to Advaita Ashrama, Mayavati, on a holiday trip, gave an illuminating discourse on the marvels of plant life.

He began by stating that a stimulus takes a certain time before it gets a response. This stimulus may be of different forms, e.g., it may be a sound stimulus, a light stimulus, an electric stimulus, and so on. The feebler the stimulus, the greater is the time it takes to elicit the response. For instance if one is called by a distant voice, one doubts whether he has been called at all, but in the case of a piercing scream, he starts up at once.

Now, the difficulty is that when the stimulus, the blow, is so strong as to get an instantaneous response, how is one to measure this infinitesimal time between the blow and the response? And this must be done absolutely free from any personal interference, so as to ensure correct results.

Dr. Bose here described how after deep thought and careful experiments and researches of several years he invented and manufactured a highly sensitive instrument which could automatically record the "response time" of a plant even to one thousandth part of a second. And in order to convey a graphic idea of the principles under which it worked, he had even made by means of a few simple things a crude form of his instrument, which helped the audience to form a clear idea of how a shock given to a plant which was experimented upon, would be recorded automatically by the apparatus by means of dots on its writing pad, and also how to ascertain the exact time each plant took to respond to the stimulus received. Thus the plant now records its own history unerringly by its own hand as it were. And that the same results are obtained each time the experiment is repeated under similar conditions, shows that this recording of the response time is a scientific phenomenon.

As an example of the similarities of reactions in plant and animal, Prof. Bose described the rhythmic activities of certain plants, in which automatic pulsations are maintained as in the animal heart. This phenomenon is exemplified by the Telegraph plant, which grows wild in the Gangetic plane; its Indian name is Bon charal or 'forest churl', the popular belief being that it dances to the clapping of the hand. There is no foundation however for this belief. It is a papilionaceous plant with trifoliate leaves, of which the terminal leaflet is large, and the two lateral, very small. Each of these is inserted on the petiole by means of pulvinule. The lateral leaflets are seen to execute pulsating movements which are apparently uncaused, and are not unlike the rhythmic movement of the heart to which we shall see later that their resemblance is more than superficial.

In the intact plant, under favourable conditions, these movements are easily observed to take place more or less continuously; but there are times when they come to a standstill. For this reason and because of the fact that a large plant cannot easily be manipulated as a whole and subjected to various changing conditions which the purpose of the investigation demands, it is desirable, if possible, to experiment with the detached petiole, carrying the pulsating leaflet. The required amputation however may be followed by arrest of the pulsating movements. But, as in the case of the isolated heart in a state of standstill, Dr. Bose found that the movement of the leaflet can be renewed, in the detached specimen, by the application of the internal hydrostatic pressure. Under these conditions, the rhythmic pulsations are easily maintained uniform for several hours. This is a great advantage, in as much as in the undetached specimen, the pulsations are not usually found to be so regular as they now become. So small a specimen, again, can easily be subjected to changing experimental conditions, such as the variation of internal hydrostatic pressure and temperature, application of different drugs, vapours and gases.

Under varying conditions the same plant has been observed to take different response times, as for instance, less in heat than in cold, less in summer than in winter, less in the morning than in the evening, and so forth. Again, different plants have different response times.

It is a remarkable fact that the mimosa is ten times as sensitive as a frog in giving the response. And the native idea that plants are of a lower order than animal life will cost many a sad disappointment.

In the course of his lecture Dr. Bose spoke of some of his startling discoveries recently made.... The lecturer gave quite a spiritual turn to his discourse as he finished it with the remark that, as it has been the earnest endeavour of scientists to minimise material friction in order to get the best results, so in our human concerns, it should be our best aim to minimise friction,--which is, Ignorance.

--Modern Review, Vol. XII, pages 314-315.

PLANT AUTOGRAPHS

HOW PLANTS CAN RECORD THEIR OWN STORY

Under the presidency of His Excellency Lord Carmichael, Prof. J. C. Bose delivered on Friday, the 17th January 1913 an interesting address on his recent researches at the Physical Laboratory of the Presidency College, Calcutta, his subject being "Plant Autographs."

Professor Bose has been long engaged in researches on the "Irritability of Plants," with results of great interest. These results have been made possible by the invention of a series of instruments of extraordinary precision and delicacy. Some of Professor Bose's instruments measure and record a thousandth of a second. Invisible movements in plants, hitherto beyond human scrutiny, have been brought within the range of immediate perception through the wonderful devices shown by the lecturer's demonstration of same on the screen.

Among those present were:--Sir William and Lady Duke, the Maharaja of Nashipur, Sir Gurudas Bannerjee, Sir Chundra Madhab Ghose, Sir Lawrence and Lady Jenkins, Sir Richard Harington, Hon. Mr. P. C. Lyon, Mr. Justice Holmwood, Mr. Justice Chaudhuri, Hon. Mr. S. L. Maddox, Maharaja of Cossimbazar, Hon. Dr. Kuchler, Mr. Bhupendra Nath Basu, Hon. Mr. E. W. Collin, Mr. W. Graham, Mr. Fraser Blair, Hon. Mr. B. Chuckerbutty, Hon. Mr. J. G. Apcar, Hon. Mr. B. C. Mitter, Hon. Rai Radha Charan Pal Bahadur, Hon. Dr. D. P. Sarbadhikari, Mr. and Mrs. Williams, Mr. L. P. E. Pugh, Mr. Lanford James, Dr. P. K. Roy, Khan Bahadur Moulvie Mahomed Yusuf, Rai Bahadur Dr. Chunilal Bose, Mr. W. J. Simmons, Mr. and Mrs. J. H. Hechle, Principal H. R. James and Mrs. James, Mr. T. J. Waite, Dr. P. C. Roy and Rai P. N. Mukherji Bahadur.

His Excellency, as President, called upon Dr. Bose to deliver his lecture.

Professor Bose commenced with a reference to the claims made by those who profess to discriminate character by handwriting. As to the authenticity of such claims, scepticism was permissible; but there was no doubt that one's handwriting might be modified profoundly by conditions, physical and mental. There still existed, at Hatfield House, documents which contained the signature of the historical Guy Fawkes. A photograph projected on the screen showed a sinister variation in those signatures. The crabbed and distorted characters of the last words which Guy Fawkes wrote on earth told their own tale of that fateful night. Such was the tale that might be unfolded by the lines and curves of a human autograph. Could plants be made similarly to write their own autographs revealing their hidden story? Storm and sunshine, the warmth of summer and the frost of winter, drought and rain, would come and go about the plants. What subtle impress did they leave behind? How were the invisible, internal changes to be made externally visible?

AUTOMATIC RECORDERS

The lecturer had succeeded in devising experimental methods and apparatus by which the plant was made to give an answering signal, which was then automatically recorded into an intelligible script. The results of the new investigations were so novel that Professor Bose spent several years in perfecting automatic instruments which completely eliminated all personal equations. The plant attached to the recording apparatus was automatically excited by a stimulus absolutely constant, making its own responsive records, going through its period of recovery, and embarking on the same cycle over again without assistance at any point from the observer. The most sensitive organ for perception of a stimulus was the human tongue. An average European could by his tongue detect an electrical current as feeble as six micro-amperes, a micro-ampere being a millionth part of a unit of electrical current. Professor Bose found that his Hindu peoples could detect a much feebler current, namely, 1.5 micro-amperes. It was an open question whether such a high excitability of the tongue was to be claimed as a distinct advantage. But the fact might explain the eminence of his countrymen in forensic domains! (Laughter.) The plant, when tested, was found to be ten times more sensitive than a human being.

EFFECT OF FOOD AND DRUGS

It was shown that when the plant had a surfeit of drink, it became excessively lethargic and irresponsive. By extracting fluid from the gorged plant, its motor activity was at once re-established. Under alcohol its responsive script became ludicrously unsteady. A scientific superstition existed regarding carbonic acid as being good for a plant. But Professor Bose's experiments showed distinctly that the gas would suffocate the plant as readily as it did the animal. Only in the presence of sunlight could the effect be modified by secondary reaction.