William Thomson (1824-1907), a resident of Glasgow, Scotland, was a leading mathematician, physical scientist, and engineer. In a long and active career, he made significant contributions to the study of thermodynamics, electricity, and magnetism. In the 1850s and 1860s, he was centrally involved in efforts to create the transatlantic telegraph cable. This engineering work brought him wide public note, and his patents for electrical devices brought him considerable wealth. Knighted in 1866 for his work on the transatlantic cable, he was honored further with a peerage and the title Baron Kelvin of Largs in 1892. The Kelvin scale of absolute temperature, developed from his initial ideas, is named for him.
Participation in cable-laying expeditions encouraged Thomson's existing interest in the sea and seafaring, and in 1870, after the death of his first wife, he purchased his own yacht. Practical experience gained aboard the yacht, coupled with his considerable scientific and engineering skill led him to develop improvements to navigational equipment, and within the decade he patented a new deep-sea sounding apparatus and made significant improvements to the marine compass.
Sir William Thomson, Mariner's Compass, U.S. patent no. 232,781, Sept. 28, 1880.
Alan Gurney, Compass: A Story of Exploration and Innovation (New York, 2004), 235 ff.