Sir Jagadish Chandra Bose

History :-


Sir Jagdish Chandra Bose was born in Bikrampur, Bengal, now Munshiganj District of Bangladesh) on November 30, 1870. His father, Bhagawan Chandra Bose, was a Brahmo and leader of the Brahmo Samaj and worked as a deputy magistrate/ assistant commissioner in Faridpur, Bardhaman and other places. His family hailed from the village Rarikhal, Bikrampur, in the current dayMunshiganj District of Bangladesh.


Bose’s education started in a vernacular school, because his father believed that one must know one's own mother tongue before beginning English, and that one should know also one's own people.[citation needed] Speaking at the Bikrampur Conference in 1915, Bose said:“At that time, sending children to English schools was an aristocratic status symbol. In the vernacular school, to which I was sent, the son of the Muslim attendant of my father sat on my right side, and the son of a fisherman sat on my left. They were my playmates. I listened spellbound to their stories of birds, animals and aquatic creatures. Perhaps these stories created in my mind a keen interest in investigating the workings of Nature. When I returned home from school accompanied by my school fellows, my mother welcomed and fed all of us without discrimination. Although she was an orthodox old fashioned lady, she never considered herself guilty of impiety by treating these ‘untouchables’ as her own children. It was because of my childhood friendship with them that I could never feel that there were ‘creatures’ who might be labelled ‘low-caste’. I never realised that there existed a ‘problem’ common to the two communities, Hindus and Muslims.”


Bose joined the Hare School in 1869 and then St. Xavier’s School at Kolkata. In 1875, he passed the Entrance Examination (equivalent to school graduation) of University of Calcutta and was admitted to St. Xavier's College, Calcutta. At St. Xavier's, Bose came in contact with Jesuit Father Eugene Lafont, who played a significant role in developing his interest to natural science. He received a bachelor's degree from University of Calcutta in 1879.


Bose wanted to go to England to compete for the Indian Civil Service. However, his father, a civil servant himself, canceled the plan. He wished his son to be a scholar, who would “rule nobody but himself.”[citation needed] Bose went to England to study Medicine at the University of London. However, he had to quit because of ill health. The odour in the dissection rooms is also said to have exacerbated his illness.


Through the recommendation of Anand Mohan, his brother-in-law (sister's husband) and the first Indian wrangler, he secured admission in Christ's College, Cambridge to study Natural Science. He received the Natural Science Tripos from the University of Cambridge and a BSc from the University of London in 1884. Among Bose’s teachers at Cambridge were Lord Rayleigh, Michael Foster, James Dewar, Francis Darwin, Francis Balfour, and Sidney Vines. At the time when Bose was a student at Cambridge, Prafulla Chandra Roy was a student at Edinburgh. They met in London and became intimate friends.


On the second day of a two-day seminar held on the occasion of 150th anniversary of Jagadish Chandra Bose on 28–29 July at The Asiatic Society, Kolkata Professor Shibaji Raha, Director of the Bose Institute, Kolkata told in his valedictory address that he had personally checked the register of the Cambridge University to confirm the fact that in addition to Tripos he received an M.A. as well from it in 1884.








Science :-






Radio research




The British theoretical physicist James Clerk Maxwell mathematically predicted the existence of electromagnetic waves of diverse wavelengths, but he died in 1879 before his prediction was experimentally verified. British physicist Oliver Lodge demonstrated the existence of Maxwell’s waves transmitted along wires in 1887-88. The German physicist Heinrich Hertzshowed experimentally, in 1888, the existence of electromagnetic waves in free space. Subsequently, Lodge pursued Hertz’s work and delivered a commemorative lecture in June 1894 (after Hertz’s death) and published it in book form. Lodge’s work caught the attention of scientists in different countries including Bose in India.


The first remarkable aspect of Bose’s follow up microwave research was that he reduced the waves to the millimetre level (about 5 mm wavelength). He realised the disadvantages of long waves for studying their light-like properties.


In 1893, Nikola Tesla demonstrated the first public radio communication. One year later, during a November 1894 (or 1895) public demonstration at Town Hall of Kolkata, Bose ignited gunpowder and rang a bell at a distance using millimetre range wavelength microwaves. Lieutenant Governor Sir William Mackenzie witnessed Bose's demonstration in the Kolkata Town Hall. Bose wrote in a Bengali essay, Adrisya Alok (Invisible Light), “The invisible light can easily pass through brick walls, buildings etc. Therefore, messages can be transmitted by means of it without the mediation of wires.” In Russia, Popov performed similar experiments. In December 1895, Popov's records indicate that he hoped for distant signalling with radio waves.


Bose’s first scientific paper, “On polarisation of electric rays by double-refracting crystals” was communicated to the Asiatic Society of Bengal in May 1895, within a year of Lodge’s paper. His second paper was communicated to the Royal Society of London by Lord Rayleigh in October 1895. In December 1895, the London journal the Electrician (Vol 36) published Bose’s paper, “On a new electro-polariscope”. At that time, the word ‘coherer’, coined by Lodge, was used in the English-speaking world for Hertzian wave receivers or detectors. TheElectrician readily commented on Bose’s coherer. (December 1895). The Englishman (18 January 1896) quoted from the Electrician and commented as follows:”Should Professor Bose succeed in perfecting and patenting his ‘Coherer’, we may in time see the whole system of coast lighting throughout the navigable world revolutionised by a Bengali scientist working single handed in our Presidency College Laboratory.”


Bose planned to “perfect his coherer” but never thought of patenting it.


In May 1897, two years after Bose's public demonstration in Kolkata, Marconi conducted his wireless signalling experiment on Salisbury Plain. Bose went to London on a lecture tour in 1896 and met Marconi, who was conducting wireless experiments for the British post office. In an interview, Bose expressed disinterest in commercial telegraphy and suggested others use his research work. In 1899, Bose announced the development of a "iron-mercury-iron coherer with telephone detector" in a paper presented at the Royal Society, London.


Bose's demonstration of remote wireless signalling has priority over Marconi. He was the first to use a semiconductor junction to detect radio waves, and he invented various now commonplace microwave components. In 1954, Pearson and Brattain gave priority to Bose for the use of a semi-conducting crystal as a detector of radio waves. Further work at millimetre wavelengths was almost nonexistent for nearly 50 years. In 1897, Bose described to the Royal Institution in London his research carried out in Kolkata at millimetre wavelengths. He used waveguides, horn antennas, dielectric lenses, various polarisers and even semiconductors at frequencies as high as 60 GHz; much of his original equipment is still in existence, now at the Bose Institute in Kolkata. A 1.3 mm multi-beam receiver now in use on the NRAO 12 Metre Telescope, Arizona, U.S.A. incorporates concepts from his original 1897 papers.


Sir Nevill Mott, Nobel Laureate in 1977 for his own contributions to solid-state electronics, remarked that "J.C. Bose was at least 60 years ahead of his time" and "In fact, he had anticipated the existence of P-type and N-type semiconductors."






Plant research


Bose's next contribution to science was in plant physiology. He forwarded a theory for the ascent of sap in plants in 1927, his theory contributed to the vital theory of ascent of sap. According to his theory, electromechanical pulsations of living cells were responsible for the ascent of sap in plants.


He was skeptical about the then, and still now, most popular theory for the ascent of sap, the tension-cohesion theory of Dixon and Joly, first proposed in 1894. The 'CP theory', proposed by Canny in 1995, validates this skepticism. Canny experimentally demonstrated pumping in the living cells in the junction of the endodermis.


In his research in plant stimuli, Bose showed with the help of his newly invented crescograph that plants responded to various stimuli as if they had nervous systems like that of animals. He therefore found a parallelism between animal and plant tissues. His experiments showed that plants grow faster in pleasant music and their growth is retarded in noise or harsh sound. This was experimentally verified later on.[citation needed]


His major contribution in the field of biophysics was the demonstration of the electrical nature of the conduction of various stimuli (e.g., wounds, chemical agents) in plants, which were earlier thought to be of a chemical nature. These claims were later proven experimentally by Wildon et al. (Nature, 1992, 360, 62–65). He was also the first to study the action of microwaves in plant tissues and corresponding changes in the cell membrane potential. He researched the mechanism of the seasonal effect on plants, the effect of chemical inhibitors on plant stimuli, the effect of temperature etc. From the analysis of the variation of the cell membrane potential of plants under different circumstances, he deduced the claim that plants can "feel pain, understand affection etc.".






Electrical response in metals


J.C. Bose was the first physicist who began an examination of inorganic matter (metals and certain rocks) 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(metals and living tissues) 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.”






Science fiction


In 1896, Bose wrote Niruddesher Kahini, the first major work in Bangla science fiction. Later, he added the story in the Abyakta book as Palatak Tuphan. He was the first science fictionwriter in the Bengali language.


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