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. Chuckerb.u.t.ty, 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, Princ.i.p.al 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, doc.u.ments 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 a.s.sistance 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 superst.i.tion 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.
AUTOMATISM AND GROWTH
It was impossible in a limited s.p.a.ce, said Professor Bose, to do more than mention the numerous other remarkable experiments which riveted the attention of the audience. By means of apparatus specially devised, pulsative plants were made to record their rhythmic throbbings. It was shown that the pulse beats of the plants were affected by the action of various drugs, and divers stimuli, in a manner similar to that of the animal heart. Perhaps the most weird experience was to watch the death-struggle of a plant under the action of poison. Turning from death to its ant.i.thesis life and growth, the audience were shown how the latter was made visible by means of the appliances invented by Professor Bose. The infinitesimal growth of a plant became highly magnified in the experiment.
RESEARCHES AT PRESIDENCY COLLEGE
When the lecturer commenced his investigations, original research in India was regarded as an impossibility. No proper laboratory existed, nor was there any scientific manufactory for the construction of a special apparatus. In spite of these difficulties it had been a matter of gratification to the lecturer that the various investigations already carried out at the Presidency College had done something for the advancement of knowledge. The delicate instruments seen in operation at the lecture, which had been regarded with admiration by many distinguished scientific men in the West, were all constructed at the College workshops by Indian mechanics.
It was also with pride that the lecturer referred to the co-operation of his pupils and a.s.sistants, through whose help the extensive works, requiring ceaseless labour by day and night, had been accomplished.
Doubt had been cast on the capacity of Indian students in the field of science. From his personal experience Professor Bose bore testimony to their special fitness in this respect. An intellectual hunger had been created by the spread of education. An Indian student demanded something absorbing to think about and to give scope for his latent energies. If this could be done, he would betake himself ardently to research into Nature, which could never end. There was room for such toilers who by incessant work would extend the bounds of human knowledge.
FROM PLANT TO ANIMAL LIFE
Before concluding the lecturer dwelt on the fact that all the varied and complex responses of the animal had been foreshadowed in the plant. The phenomena of life in the plant were thus not so remote as had been hitherto supposed. The plant world, like the animal, was a thrill and a throb with responsiveness to all the stimuli which fell upon it. Thus, community throughout the great ocean of life, in all its different forms, outweighed apparent dissimilarity. Diversity was swallowed up in unity.
--_Amrita Bazar Patrika_, 20-1-1913.
INVISIBLE LIGHT
A most instructive and interesting lecture was delivered on Thursday, the 30th January, 1913, at the Calcutta University Inst.i.tute Hall, by Dr. J. C. Bose, on the above subject. It was ill.u.s.trated with experiments and in spite of the technical nature of the subject, the manner of treatment made the discourse extremely palatable and easy of apprehension to the lay understanding and intelligence. The truths of science could seldom be exposed so light-heartedly and in language leavened with balmy humour. The lecture was very largely attended by ladies and gentlemen, European and Indian, representing the light and leading of the city. The chair was taken by Mr. W. R. Gourlay. Amongst those present we noticed the Hon. Mr. Ramsay McDonald, Mr. Justice Harington, Mr. Justice Chaudhuri, Hon"ble Mr. Gokhale, Hon"ble Mr. Lyon, Hon"ble Mr. D. N. Sarvadhikari, Sir Gurudas Banerji, Hon"ble Mr. Apcar and Dr. Chuni Lal Bose Rai Bahadur.
The Chairman, in a few well chosen words introduced the lecturer.
Professor Bose in going to deliver his highly interesting lecture first showed how on account of the imperfection of our senses we fail to detect various forces which play around us. We are not only deaf, but practically blind. While we perceive eleven octaves of sound, we can see only a single octave of other vibration which is called light. In order to detect the invisible light a special detector has to be devised.
Prof. Bose showed his artificial retina previously exhibited at the Royal Inst.i.tution which not only detected luminous radiation but also invisible lights in the intra red and ultra violet regions. In the course of his remarks ill.u.s.trating the nature of electric or Hertzian waves, which gave rise to the invisible radiation he proceeded to enumerate some of the conditions necessary for experimenting with them, and to describe the apparatus he had invented for the purpose. Hertz had used waves which were about 10 metres in length. It was impossible to attempt any quant.i.tative measurement of their optical properties on account of large waves curling round corners. The lecturer had succeeded in producing the shortest waves, with frequency of 50,000 millions of vibrations per second, the particular invisible radiation being only thirteen octaves below visible light. His generator produced the small sharp beam which alone could be employed for quant.i.tative measurements.
By means of this apparatus experiments on electric radiation could be carried on with as much certainty as could experiments with ordinary light. Prof. Bose then performed experiments ill.u.s.trative of the properties possessed in common by light waves and electric waves. He exhibited the power of selective absorption to electric rays displayed by many substances pointing out that while water stopped them, pitch, coal tar, and others were quite transparent to them. He showed how the rays were reflected by mirrors, obeying the same laws as light. The hand of the experimenter was found to be a good reflector, the rays rebounding after impact. Electric rays also undergo refraction and he described an ingenious method he had devised by which the index of refraction of numerous opaque substances could be obtained with the highest exact.i.tude. In conclusion he gave an account of his discovery of the polarisation of electric rays by crystals. He showed that these polarised the electric rays just as they did ordinary light. He further proved that substances under pressure and strain could produce double refraction in them, as did gla.s.s under the same conditions in light.
Tourmaline was useless for electric rays; but a lock of human hair was extraordinarily efficient. According to this theoretical prediction, an ordinary book was shown to exhibit selective absorption in a striking manner. Thus while the Calcutta University Calendar was, usually, very opaque, it became quite transparent when held in a particular direction as regards the impinging ray.
Mr. Gourlay observed that the lecture opened out to himself, as well as to other vistas, which they had never dreamt of before.
--_Amrita Bazar Patrika_, 31-1-1913.
PROFESSOR J. C. BOSE AT LAh.o.r.e
LECTURE ON ELECTRIC RADIATION
A crowded a.s.sembly met at the University Hall, on the 22nd February, 1913, to hear the first of Prof. Bose"s discourses before the University of Lah.o.r.e.
Dr. Bose opened his address by alluding to the historic journey of Jivaka, who afterwards became the physician of Buddha, making his way from Bengal to the University of Taxila, in quest of knowledge.
Twenty-five centuries had gone by and there was before them another pilgrim who had journeyed the same distance to bring, as an offering what he had gathered in the domain of knowledge.
The lecturer called attention to the fact that knowledge was never the exclusive possession of any particular race nor did it ever recognise geographical limitations. The whole world was interdependent, and a constant interchange of thought had been carried on throughout the ages enriching the common heritage of mankind. h.e.l.lenistic Greeks and Eastern Aryans had met here in Taxila to exchange the best each had to offer.
After many centuries the East and West had met once more, and it would be the test of the real greatness of the two civilisations that both should be finer and better for the shock of contact. The apparent dormancy of intellectual life in India had been only a temporary phase.
Just like the oscillations of the seasons found the globe, great pulsations of intellectual activity pa.s.s over the different peoples of the earth.
With the coming of the spring the dormant life springs forth; similarly the life that India conserves, by inheritance, culture and temperament, was only latent and was again ready to spring forth into the blossom and fruit of knowledge. Although science was neither of the East nor of the West, but international in its universality, certain aspect of it gained richness of colour by reason of their place of origin. India, perhaps through its habit of synthesis, was apt to realise instinctively the idea of unity and to see in the phenomenal world an universe instead of a multiverse. It was this tendency, the lecturer thought, which had led Indian physicist, like himself, when studying the effect of forces on matter to find boundary lines vanishing, and to see points of contact emerge between the realms of the living and non-living. In taking up the subject of the evening"s discourse on electric radiation of Hertzian waves, the lecturer explained the const.i.tution of the apparatus which he had devised for an exhaustive study of the properties of electric waves.
His apparatus permitted experiments with the electric rays to be carried on with as much certainty as experiments with ordinary light, and he demonstrated the ident.i.ty of electric radiation and light. The electric rays are reflected from plane and curved mirrors in the same way and subject to the same laws. Electric rays, like rays of light are refracted. Like race of light too, electric waves can be selectively stopped by various substances, which are "electrically" coloured. Water which is a conductor of electricity stops the electric ray; where as liquid air which is a non-conductor is quite transparent to the rays.
Finally Professor Bose explained his discovery of Polarisation of these rays by various crystals. Tourmaline, which was a good polariser for ordinary light, was not so effective. The lecturer discovered that the crystal Nemalite possessed the power of polarising the electric rays in the most perfect manner. Professor Bose also explained how the internal const.i.tution of an opaque ma.s.s was revealed by the help of light which was itself invisible.
The lecturer concluded his discourse by drawing attention to the limitations of human perception. Man"s power of hearing was confirmed to eleven octaves of sound notes. In the case of vision the limitation was far more serious, his power of sight extending only through a single octave of those ether waves which const.i.tuted light. These ether vibrations of various frequencies could be maintained by electrical means. By pressing the stop b.u.t.ton of the apparatus which was exhibited, ether vibrations, 50,000 millions per second, were produced. A second stop gave rise to a different vibration. Let his audience imagine a large electric organ provided with an infinite number of stops, each stop giving rise to a particular ether note. Let the lowest stop produce one vibration a second. They should then get a gigantic wave of 186,000 miles long. Let the next stop give rise to two vibrations in a second, and let each succeeding stop produce higher and higher notes. Let them imagine an unseen hand pressing the different stops in rapid succession, producing higher and higher notes. The ether note would thus rise in frequency from one vibration in a second, to tens, to hundreds, to thousands, to hundreds of thousands, to millions, to millions of millions! While the ethereal sea in which they were all immersed were being thus agitated by these mult.i.tudinous waves, they would remain entirely unaffected, for they possessed no organs of perception, to respond to these waves.