This is a life of Lord Kelvin, who began life as William Thomson, matriculated at Glasgow University at the age of 10 and entered Cambridge University at 17. By the time he was 22, he was back again at Glasgow, but this time as Professor of Natural Philosophy. He had now published the first 20 of a total output of 66 scientific papers and many textbooks. Later, he became the originator of more than 70 patents which were, contrary to the normal fate of many patents, all profitable. Knighted in 1866 for his work on the Atlantic cable project, he was raised to the peerage in 1892, in which year he became President of the Royal Society - the highest scientific honour England could bestow upon him. He was three times President of the Institution of Electrical Engineers. A gigantic task faced physicists at the middle of the 19th century. As Kelvin put it, during a lecture on electrical measurement, "...Poisson and Green, and Gauss, and Weber, and Ohm, and Lentz, and Faraday, and Joule, this century, had given us the mathematical and experimental foundation, for a complete system of numerical reckoning...and as early as 1858 a practical beginning of definite electric measurement had been made. ..but fifteen years passed after this beginning before anything that could be called electric measurement, had come to be regularly practised in most of the scientific laboratories of the world". Kelvin was the first to recognize the necessity for a solid scientific foundation for electrical units and standards, and he, more then any other, paved the way for their establishment and eventual international adoption. His insistence on the metric system, and his monumental work in the British Association for the advancement of Science and later at the International Electrical Congresses, beginning with Paris in 1881, continued unceasingly until his death in 1907. Kelvin's great accomplishment was to bring together all the experimental scientists of his time into one co-operative association for investigators whose individual efforts were aided by their combined results, expressed in a notation and described in language understood by everyone.