قراءة كتاب Sir Jagadis Chunder Bose, His Life and Speeches

تنويه: تعرض هنا نبذة من اول ١٠ صفحات فقط من الكتاب الالكتروني، لقراءة الكتاب كاملا اضغط على الزر “اشتر الآن"

‏اللغة: English
Sir Jagadis Chunder Bose, His Life and Speeches

Sir Jagadis Chunder Bose, His Life and Speeches

تقييمك:
0
No votes yet
المؤلف:
دار النشر: Project Gutenberg
الصفحة رقم: 5

laboured under one great disadvantage. The 'receiver' had to be tapped between each experiment. So something better than a 'cohering' receiving was needed—something that was self-recovering, like a human eye. To discover that something, Dr. Bose began a study of the whole theory of 'coherer action.' It was hitherto believed that the electric waves, by impinging on iron and other metallic particles in contact, brought about a sort of fusion—a sort of 'coherence'—and that the diminution of resistance was the result of that 'coherence.' To satisfy himself as to the correctness of this theory, Dr. Bose engaged himself in a most laborious investigation to find out the action of electric radiation not only on iron particles but on all kinds of matter and ultimately discovered the surprising fact that, though the impact of electric waves generally produced a diminution of resistance, with potassium there was an increase of resistance after the waves had ceased.11 This discovery at once showed the untenability of the old theory and pointed to the conclusion that the effect of electric radiation on matter is one of discriminative molecular action—that the Electric Waves produced a re-arrangement of the molecules which may either increase or decrease the contact resistance. It may be incidentally mentioned here that this detection of molecular change in matter under electric stimulation has given rise to a new theory of photographic action.

As a result of his painstaking investigation on the action of Electric Waves on different kinds of matter, Dr. Bose invented a new type of self-recovering electric receiver, "so perfect in its action that the Electrician suggested its use in ships and in electro-magnetic light-houses for the communication and transmission of danger-signals at sea through space. This was, in 1895, several years in advance of the present wireless system." Practical application of the results of Dr. Bose's investigations appeared so important that the Governments of Great Britain and the United States of America granted him patents for his invention of a certain crystal receiver which proved to be the most sensitive detector of the wireless signal. Dr. Bose, however, has made no secret at any time as to the construction of his apparatus. He has never utilised the patents granted to him for personal gain. His inventions are "open to all the world to adopt for practical and money-making purposes." "The spirit of our national culture" observes Sir J. C. Bose "demands that we should for ever be free from the desecration of utilising knowledge for personal gain."12

HIS RESEARCHES TAKE A NEW TURN

This inquiry which Dr. J. C. Bose started for the purpose of ascertaining 'coherer action'—why the "receiver" had to be tapped in order to respond again to electric waves—took him unconsciously to the border region of physics and physiology and gave an altogether new turn to his researches. "He found that the uncertainty of the early type of his receiver was brought on by 'fatigue' and that the curve of fatigue of his instrument closely resembled the fatigue curve of animal muscle."13 He did not stop there but pushed on his investigations and found "that the 'tiredness' of his instrument was removed by suitable stimulants and that application of certain poisons, on the other hand, permanently abolished its sensitiveness." He was amazed at this discovery—this parallelism in the behaviour of the 'receiver' to the living muscle. This led him to a systematic study of all matter, Organic and Inorganic, Living and Non-Living.

RESPONSE IN LIVING AND NON-LIVING

He began an examination of inorganic matter in the same way as a biologist examines a muscle or a nerve. He subjected metals to various kinds of stimulus—mechanical, thermal, chemical, and electrical. He found that all sorts of stimulus produce an excitatory change in them. And this excitation sometimes expresses itself in a visible change of form and sometimes not; but the disturbance produced by the stimulus always exhibits itself in an electric response. He next subjected plants and animal tissues to various kinds of stimulus and also found that they also give an electric response. Finding that a universal reaction brought together metals, plants and animals under a common law, he next proceeded to a study of modifications in response, which occur under various conditions. He found that they are all benumbed by cold, intoxicated by alcohol, wearied by excessive work, stupified by anaesthetics, excited by electric currents, stung by physical blows and killed by poison—they all exhibit essentially the same phenomena of fatigue and depression, together with possibilities of recovery and of exaltation, yet also that of permanent irresponsiveness which is associated with death—they all are responsive or irresponsive under the same conditions and in the same manner. The investigations showed that, in the entire range of response phenomena (inclusive as that is of metals, plants and animals) there is no breach of continuity; that "the living response in all its diverse modifications is only a repetition of responses seen in the inorganic" and that the phenomena of response "are determined, not by the play of an unknowable and arbitrary vital force, but by the working of laws that know no change, acting equally and uniformly throughout the organic and inorganic matter."14

SECOND SCIENTIFIC DEPUTATION, 1900-01

In the year 1900, the International Scientific Congress was held, in Paris. And Dr. J. C. Bose was deputed by the Government of India to the Congress as a delegate from this country. Before the assembled scientists, Dr. Bose delivered a remarkable address on the results of his researches on the similarity of Response of Inorganic and Living Substances to Electric stimulus ... 'De la gênêralitê de Phênomênes Moleculairs produits par l'Ectricité sur la matiriê Inorganique et sur la matiêre Vivante.' He next read a paper 'On the Similarity of effect of Electric Stimulus on Inorganic and Living Substances' before the Bradford meeting of the British Association in 1900. He then contributed a very interesting paper 'on Binocular Alteration of Vision,' which was published by the Physiological Society of London, in November 1900. It may be mentioned here, by the way, that, in course of his investigations on the Response of the Living and Non-Living substances, Dr. Bose constructed an "artificial retina" to study the characteristics of the excitatory change produced by a stimulus on the retina and these characteristics gave him a clue to the unexpected discovery of the "binocular alteration of vision" in man—"each eye supplements its fellow by turns, instead of acting as a continuously yoked pair, as hitherto believed."

Pages