Monday, January 06, 2014
Focus on Asia: Early Wireless Experiments in India
It was back in the year 1849, more than one and a half centuries ago, that the first wireless experiments took place in old British India. At the time, the illustrious 30 year old German speaking Queen Victoria was on the throne in England; there were just 30 states in the United States; and India was under the control of the East India Company. The capital city of India back then was Calcutta, the second largest city in the British Empire, with London as the largest.
In the said year, 1849, Dr. Sir William O’Shaughnessy, Superintendent of Telegraphs in Calcutta, successfully transmitted wireless signals across the Huldee River three forth mile wide. He laid two wires along the banks of the River Huldee, one on each side, with a metal plate at each end of each wire, with the metal plates immersed in the water.
The active wire was powered from 250 battery cells filled with nitric acid and a platinum electrode in each, making the project prohibitively expensive. Communication was achieved across the wide river, though with difficulty. Nine years later, he performed a similar experiment across the waters of Lake Ootacamund in Tamilnadu South India.
A subsequent superintendent of the Indian Telegraph Department was a Mr. Blissett. In 1858, he conducted similar wireless experiments with the use of a long wire on each bank of a river and in this way achieved fair success.
In 1873, a Mr. Winter in India made some astute observations regarding cross modulation of Morse signals between parallel telegraph wires on the same poles.
An electrician with the telegraph department, Mr. Schwendler, carried out similar cross-river communications in the same way as his predecessors. His experiments were conducted across the River Hooghly at Barrackpore, near Calcutta, using parallel wires with metal plates submerged in the water. That was in the year 1876.
Another subsequent electrician with the telegraph department was Mr. W. P. Johnston and he repeated the same experiments across a nearby waterway 200 yards wide. That was on September 9, 1879. Nine years later, he carried out many similar experiments across nearby canals in the Calcutta area, and also across the River Hooghly itself.
Mr. Johnston died in April 1889, and his position was taken over by Mr. Melhuish, who also conducted similar experiments with the use of water as a conducting medium. He discovered that the wires lying on the bank on each side of the river need to be at least as long as the river is wide, in order to achieve reliable communication.
It should be remembered that all of these early wireless experiments in India involving cross-water communication during the 1800s were conducted in Morse Code.
The first experimental work on the transmission and reception of radio signals in India was carried out by Dr. Sir Jagadish Chandra Bose. He was born in 1858 near Dhaka in Bangladesh, though in those days that territory formed part of the province of Bengal in old British India.
It was towards the end of the year 1894 that Bose began his experimentation with wireless; and in November 1895, he gave a public demonstration in the Calcutta Town Hall with Bengal’s Lieutenant Governor Sir William Mackenzie in attendance. In this public demonstration, Bose transmitted wireless signals at a wavelength of just ½ inch over a distance of 75 ft through several solid walls. He also used a wireless signal to ring a bell at a distance, and to fire a gun remotely.
On two separate occasions, Bose gave public lectures in London England in which he presented details of his wireless experiments in Calcutta India. His 1897 lecture was before the Royal Institution, and two years later his lecture was before the Royal Society. In his 1899 presentation, Bose gave details of the coherer receiver that he had developed, and it is understood that the young Italian experimenter Marconi incorporated the Bose coherer in his own subsequent public demonstrations in England.
(AWR Wavescan/NWS 254)