Remembering two giants of Indian science

N. Gopal Raj

Plaques commemorating the achievements of two titans of Indian science, Sir Jagadis Chandra Bose and Sir C.V. Raman, are to be unveiled in Kolkata on Friday (September 14).

The plaques are being put up as part of the ‘Milestones in Electrical Engineering and Computing’ of the Institute of Electrical and Electronics Engineers (IEEE), a professional body with members from 160 countries. It established the Milestones programme in 1983 to recognise “technological innovation and excellence for the benefit of humanity.”

Guglielmo Marconi is often credited with inventing radio transmission and shared the 1909 Nobel Prize in Physics with Ferdinand Braun for ‘development of wireless telegraphy.’

First to do

“But the record clearly shows that wireless transmission of electromagnetic waves was first successfully demonstrated by Bose and that too in Calcutta [now Kolkata], not London or elsewhere” remarked Ranjit Nair, director of the Delhi-based Centre for Philosophy and Foundations of Science.

Dr. Nair had helped organise a symposium in 2008 to mark the great scientist’s 150 birth anniversary at his alma mater, Christ’s College at Cambridge in the U.K.

The first demonstration by Bose, using apparatus he had designed and built, took place in 1895 at Presidency College (now Presidency University) where he taught, according to Sibaji Raha, director of the Bose Institute in Kolkata. The transmitter, which generated the wireless signal was put in a colleague’s room while the detector was in an adjoining room with the principal of the college, Sir Alexander Pedler, himself a chemist of some renown, present. The wireless signal went through a closed door, rang a bell and set off some gunpowder.

Public demonstration

Soon thereafter, Bose held a public demonstration at the Town Hall in the presence of the Lt. Governor of Bengal, said Dr Raha in an email.

In 1897, Bose reported on his experiments at the Royal Institution in London. Marconi, who had moved from Italy to England by that time, was not getting the desired result with his efforts at transmission.

But soon after Bose’s talk, Marconi changed the design of his detector to one that was “uncannily similar” to the one the former had designed and successfully demonstrated. Later that year, Marconi carried out his first successful demonstration of wireless signalling, Dr. Raha pointed out.

Moreover, Bose made use of galena crystals in his detectors, presaging work in semi-conductors that revolutionised electronics many decades later.

The plaque for Bose will be at Presidency University. The one for Raman is being placed at the current premises of the Indian Association for the Cultivation of Science (its original building, where he carried out his experimental work for many years, is now a college of commerce).

When light is scattered by an atom or molecule, it can gain or lose energy in the process, leading to a change in colour of the light that bounces off. Raman found that this colour change was related to the properties of the material that caused the scattering.

The ‘Raman Effect,’ for which he won the Nobel Prize in 1930, has become an invaluable analytical tool in a wide range of fields, from industrial chemistry to life sciences and forensic investigations, for establishing the chemical composition and molecular structure of materials.

Raman scattering is now entering the realm of fibre optic communications that are the backbone of the digital world of today. Fibre optic cables that girdle the globe move zillions of bits every second to every part of this planet.

“There is still an ever-increasing demand for bandwidth due to an explosive increase in the volume of internet data, voice and video to be transferred,” said Deepa Venkitesh of the Department of Electrical Engineering at Indian Institute of Technology Madras. “Amplifiers based on the ‘Raman Effect’ are becoming the preferred choice to meet this demand.”