Jagadish Chandra Bose
Physicist turned plant biologist Jagadish Chandra Bose was born on 30 November 1858 in Mymensingh, India (now in Bangladesh) to a well-to-do family. His father Bhagabanchandra Bose was a Deputy Magistrate. A distinguished student, he began attending St. Xavier’s College, Calcutta in 1875 and received the BA degree from Calcutta University in 1877. In 1880 the twenty-two-year old Bose left India for England. For a year he studied medicine at London University, England, but had to give it up because of his own ill health. Within a year he moved to Cambridge to take up a scholarship to study Natural Science at Christ's College Cambridge. One of his lecturers at Cambridge was Professor Rayleigh, who clearly had a profound influence on his later work. He graduated from there in 1884 with a Natural Science Tripos (a special course of study at Cambridge). That same year Bose also received the BS degree from London University. Just one year later Bose became a Professor of Physical Science at Presidency College of Calcutta, where for the next 30 years he taught and conducted research. As a teacher Bose was very popular and engaged the interest of his students by making extensive use of scientific demonstrations. Many of his students at the Presidency College were destined to become famous in their own right - for example S.N. Bose, later to become well known for the Bose-Einstein statistics.
In 1894, J.C. Bose converted a small enclosure adjoining a bathroom in the Presidency College into a laboratory. He carried out experiments involving refraction, diffraction and polarization. To receive the radiation, he used a variety of different junctions connected to a highly sensitive galvanometer. He plotted in detail the voltage-current characteristics of his junctions, noting their non-linear characteristics. He developed the use of galena crystals for making receivers, both for short wavelength radio waves and for white and ultraviolet light. Patent rights for their use in detecting electromagnetic radiation were granted to him in 1904. In 1954 Pearson and Brattain gave priority to Bose for the use of a semi-conducting crystal as a detector of radio waves. Sir Neville 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." In 1895 Bose gave his first public demonstration of electromagnetic waves, using them to ring a bell remotely and to explode some gunpowder. In 1896 the Daily Chronicle of England reported: "The inventor (J.C. Bose) has transmitted signals to a distance of nearly a mile and herein lies the first and obvious and exceedingly valuable application of this new theoretical marvel."
During the years 1894-1900, Bose performed pioneering research on radio waves and created waves as short as 5 mm. Bose’s work actually predates that of Guglielmo Marconi who is most often associated with the development of radio. Unlike Marconi who sought to commercialize his work with radio waves, Bose was purely interested in radio waves as a scientific endeavor. Bose also developed equipment for generating, transmitting, and receiving radio waves and used it to demonstrate conclusively the waves’ properties such as reflection, total reflection, refraction, double refraction, and polarization. Bose also experimented with galena to form an early type of semiconductor diode, which may be used as a detector of electromagnetic waves. 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. Outside of India he is rarely given the deserved recognition. Further work at millimeter wavelengths was almost nonexistent for nearly 50 years. J.C. Bose was at least this much ahead of his time. Research into the generation and detection of millimeter waves, and the properties of substances at these wavelengths, was being undertaken in some detail one hundred years ago, by J.C. Bose in Calcutta.
After about 1900, Bose began pursuing another longtime interest—animal and plant physiology. This included studies of the effects of electromagnetic radiation on plants, a topical field today. His contributions to this field were pioneering. He introduced many delicate and sensitive instruments, such as the Chrestograph, which was used for recording plant growth. It could magnify a small movement as much as a million times. Another device he developed demonstrated the effects of electromagnetic waves on living and nonliving matter.
Bose retired in 1915 and was appointed Emeritus Professor, Presidency College, Calcutta, for a period of 5 years. In 1917 he founded the Bose Research Institute in Calcutta which was the first scientific research institute in India. That same year a knighthood was conferred on Bose. In 1920 he became the first Indian scientist to be elected to Great Britain’s prestigious Royal Society.
Bose traveled frequently to Europe and the United States on various scientific missions and gave lectures on electromagnetic waves, the effects of electromagnetic waves on living and nonliving matter, and plant physiology. On a personal level, Bose believed in the free exchange of scientific knowledge and strongly believed that knowledge grows by sharing it with fellow scientists. Bose died on 23 November 1937 at the age of 78.
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