Subject: J C BOSE AND BIRBAL SAHNI Submitted by :Ponnu Jacob Submitted to : Mrs.Sijji (Development and resources in educational technology) Class : I B.Ed Option : Natural Science Roll No :31

MANGALAM COLLEGE OF EDUCATION

JAGADISH CHANDRA BOSE

Born: November 30,1858Died: November 23,1937

BIOGRAPHYJagdish Chandra Bose was an eminent

Indian scientist. He was the first to prove that plants and metals too have feelings.

Jagdish Chandra Bose was born on November 30, 1858 in Mymensingh (now in Bangladesh). His father Bhagabanchandra Bose was a Deputy Magistrate. Jagadish Chandra Bose had his early education in village school in Bengal medium. In 1869, Jagadish Chandra Bose was sent to Calcutta to learn English and was educated at St. Xavier's School and College. He was a brilliant student. He passed the B.A. in physical sciences in 1879.

In 1880, Jagdish Chandra Bose went to England. He studied medicine at London University, England, for a year .

Within a year he moved to Cambridge to take up a scholarship to study Natural Science at Christ's College Cambridge. In 1885, he returned from abroad with a B.Sc. degree and Natural Science Tripos .

After his return Jagadish Chandra Bose, was offered lectureship at Presidency College, Calcutta . As a teacher JC 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. These included Satyendra Nath Bose and Meghnad Saha.

In 1894, Jagadish Chandra Bose decided to devote himself to pure research. He converted a small enclosure adjoining a bathroom in the Presidency College into a laboratory. He carried out experiments involving refraction, diffraction and polarization. In 1895, a year before Guglielmo Marconi patented this invention, he had demonstrated its functioning in public.

Jagdish Chandra Bose later switched from physics to the study of metals and then plants. He fabricated a highly sensitive "coherer", the device that detects radio waves. He found that the sensitivity of the coherer decreased when it was used continuously for a long period and it regained its sensitivity when he gave the device some rest. He thus concluded that metals have feelings and memory.

Jagdish Chandra Bose died on November 23, 1937.

CONRTRIBUTIONSSir J.C. Bose did his original scientific work in the

area of Microwaves. He produced extremely short waves and did

considerable improvement upon Hertz's detector of electric waves.

He produced a compact apparatus for generating electromagnetic waves of wavelengths 25 to 5 mm and studying their quasioptical properties, such as refraction, polarization and double refraction. The most satisfactory polarizers and analyzers were made out of pressed jute fibres or books with laminated pages.

DISCOVERYBose's research on response in living and

non-living led to some significant findings: in some animal tissues stimulation produces change in form as well as electrical excitation, while in other tissues stimulation by light produces electric changes only but no change of form. He showed that not only animal but vegetable tissues under different kinds of stimuli-mechanical, application of heat, electric shock, chemicals, drugs- produce similar electric responses.

INVENTIONSThe Galena detector developed by

Bose Bose could successfully produce a flash of radiation by pressing a key; the waves were only about half an inch in length; while the receiver was so sensitive that it responded to the feeblest electric reaction. 

OTHER INVENTIONSMICROWAVE TRANSMITTER & RECEIVER

BIRBAL SAHINI

BORN 14th November 1891 DIED 10th April 1949

BIOGRAPHYThe third son of Ishwar Devi and Lala Ruchi

Ram Sahni, Birbal Sahni was born in Bhera , Shahpur District , West Punjab, on 14 November 1891.

 He got his early education in India at Government College University, Lahore and Punjab University (1911).

He was also influenced into science by his grandfather who owned a banking business at Dera Ismail Khan and conducted amateur research in chemistry

He learnt botany under S. R. Kashyap. He graduated from Emmanuel College, Cambridge in 1914. He later studied under Professor A. C. Seward, and was awarded the DSc degree of the University of London in 1919.

In 1920 he married Savitri Suri. Savitri took an interest in his work and was a constant companion.

 Sahni returned to India and served as Professor of Botany at Banaras Hindu University, Varanasi and Punjab University for about a year. He was appointed the first Professor and Head of the Botany Department of the Lucknow University in 1921.

 He was a founder of The Paleobotanical Society which established the Institute of Palaeobotany on 10 September 1946 which initially functioned in the Botany Department of Lucknow University but later moved to its present premises at 53 University Road, Lucknow in 1949. On 3 April 1949 the Prime Minister of India Jawaharlal Nehru laid the foundation stone of the new building of the Institute.

A week later, on 10 April 1949, Sahni succumbed to a heart attack.

 

RecognitionThe University of Cambridge recognised Sahni’s

researches by the award of the degree of Sc. D. in 1929.

He was recognised by several academies and institutions in India and abroad for his research. He was elected a Fellow of the Royal Society of London in 1936, the highest British scientific honour, awarded for the first time to an Indian botanist.

He was elected Vice-President, Palaeobotany section, of the 5th and 6th International Botanical Congresses of 1930 and 1935, respectively; General President of the Indian Science Congress for 1940; President, National Academy of Sciences, India, 1937–1939 and 1943–1944.

In 1948 he was elected an Honorary Member of the American Academy of Arts and Sciences. Another high honour which came to him was his election as an Honorary President of the International Botanical Congress, Stockholm in 1950, but he died before he could serve.

After his demise, Sahni's samadhi was placed within the Institute of Paleobotany as a reminder of his ground-breaking work.

Contributions and influencesIn their book Historical perspective of early

twentieth century Carboniferous paleobotany in North America, William Darrah et al. have mentioned multiple interactions of scientists with Birbal Sahni regarding fieldwork.

In his speeches, former President of India Sarvepalli Radhakrishnan has mentioned Birbal Sahni in several contexts, including science, religion etc.

The Hindu described Sahni as the "Pioneer of palaeobotany" (in India).

 

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