ponnu

2. 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

3. JAGADISH CHANDRA
BOSE
Born: November 30,1858
Died: November 23,1937

4. BIOGRAPHY
 Jagdish 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.

5.  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

6.  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

7. CONRTRIBUTIONS
 Sir 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.

8. DISCOVERY
 Bose'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.

9. INVENTIONS
The 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.

10. OTHER INVENTIONS
MICROWAVE TRANSMITTER & RECEIVER

11. BIRBAL SAHINI
BORN 14th November 1891
DIED 10th April 1949

12. BIOGRAPHY
 The 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

13.  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.

14.  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.

15. Recognition
 The 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

16.  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.

17. Contributions and influences
 In 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).

18. Thank