Biography
Heaviside, Oliver (b. May 18, 1850), London. d. Feb 3, 1925, Torquay British physicist and mathematician whose theoretical work played a large part in the understanding of radio transmissions and long distance telephony. In 1902 his famous prediction about an ionised layer in the atmosphere which would deflect radio waves was published in an article titled "Telegraphy" in the tenth edition of "Encyclopaedia Britannica." The idea came when he was considering the analogy between the movement of electric waves along a pair of conducting wires and over a conducting earth. Discussing the possibility of radio waves being guided around a curved path he suggested: "There may be a sufficiently conducting layer in the upper air. If so, the waves will, so to speak, catch on to it more or less. Then guidance will be by the sea on one side and the upper layer on the other." The layer was first named the Heaviside Layer and later as the Kennelly-Heaviside Layer as a similar prediction had been made around the same time by Arthur Kennelly at Harvard University. The hypothesis was proved correct when in 1924 radio waves being received from the upper atmosphere showed that deflection of upward signals took place at a height of around 100 kilometres. A most significant contribution to electrical communications (and a good example of his advanced thinking) came when he advocated the introduction of additional capacitance in long-distance telephony cables although there was then no practical means to add it. His idea was eventually patented by Michael Campbell of AT & T after he and George Pupin of Columbia University had shown it was possible to apply inductance in the form of uniformly spaced loading coils. By 1920 engineers had installed such loading on thousands of miles of cable, particularly in the USA. In 1873 he was inspired by Maxwell's treatise on Electricity and Magnetism. It took him several years to fully understand the book, which he then set aside and followed his own course of thinking. He also derived inspiration from his uncle, Charles Wheatstone, who in 1837 with W.F. Cooke patented the electric telegraph and later devised the Wheatstone bridge, an electrical network for measuring resistance. In 1874 he established the ordinary symbolic method of analysing alternating current circuits in common use today. It was a technique developed about fifteen years before AC came into commercial use. He emphasised the role of metallic circuits as guides, rather than conductors of AC currents. He discussed in detail the causes of line distortion and suggested ways of alleviating it. Finding Maxwell's conventional mathematics was not easily applicable to practical matters he evolved a new point of view by introducing a simpler treatment without, in his opinion, impairing accuracy. It proved to be controversial. His proofs did not conform to the mathematical standards of rigor then in fashion and his methods on partial differential equations had varying success. His most significant work was done somewhere between 1870 and 1875. In 1872 his first paper "Comparing of Electromotive Forces" was published followed by a second paper in 1873 which attracted the attention of Maxwell. By 1875 Heaviside was becoming quite well-known and in 1877 his main research work was done. Between 1880 and 1887 he developed his operational form of calculus. a branch of mathematics that permits the manipulation of varying quantities applicable to practical problems including such matters as electrical circuits with varying voltages and currents. Educated at Camden House School, London, he came fifth in the College of Preceptors examination out of 500 pupils. He left school in 1866 and continued to study. He learned Morse code, studied electricity and languages and in 1868 he went to Denmark and became a telegraph operator and in 1870 was appointed Chief Telegraph Operator. In 1871 he returned to England to take up a post with the Great Northern Telegraph Company dealing with overseas traffic. In 1875 he had to leave the job due to increasing deafness from which he suffered all his life. Encouraged by his uncle, Wheatstone, he continued with his own research into electricity. The greatest honour he received was in 1891 when he was elected a Fellow of the Royal Society (F.R.S) after being recognised as a leading authority whose research into electromagnetic waves had penetrated further than anyone had yet really understood. He was later the first recipient of the Society's Faraday Medal. The first volume of his great work "Electromagnetic Theory" was published in 1893 and a second volume in 1889. A third volume was published in 1912 but he died before the fourth and concluding one was finished. Her made an extensive contribution to pure mathematics and its practical applications to alternating current, vector analysis and telegraphy; introduced new concepts which later became commonplace thinking and expressions for every electrical engineer and invented much of the language now basic to communication with such words as capacitance, inductance, impedance and attenuation. His last years were spent as an embittered recluse at Torquay in Devon where he allowed only a few people to have access to him. He had an impish sense of humour and was considered an oddity. For much of his life he suffered from recurring jaundice which was to finally prove fatal. Heaviside's work has been an inspiration to countless electrical engineers and mathematicians. Time has enhanced the esteem in which he is held and justified the hours of study donated to his writings by succeeding generations. The imprint of his ideas will remain. He had craters on the Earth's moon and Mars named after him. Alan Heather, August 2005 |