Cumming , Alexander , 1731/2-1814 , watchmaker and mechanician

Born in Edinburgh. Son of James Cumming of Duthil, Inverness-shire. Taken into service by Lord Milton on account of his precocious mechanical skill. Member of the Philosophical Society of Edinburgh. Working in Inverary, Argyll as watchmaker and enrolled as burgess by 1752. With his brother John employed by Duke fo Argyll in making a new organ for his castle at Inverary, and a long case clock for the castle. Argyll's family connections with John Stuart, third Earl of Bute and tutor to George III led to patronage and Cumming's establishment in New Bond Street London. His reputation led him to be appointed a member of the commission to adjudicate on John Harrisons's 'timekeeper for discovering the longitude at sea'. One of those who insisted that a second timekeeper be made according to Harrison's principles to prove he had both fully disclosed his methods and had invented a reliable means of checking longitude. His essay 'Elements of Clock and Watch Work Adapted to Practice' printed in 1766 where he outlined his ideas about clockwork and included one fo the earliest designf for a gravity escarpment, seemingly arose when he was appointed to the commission on Harrison's timekeeper, and he deposited it with the Philosophicle Society of Edinburgh to protect himself against the possibility of charges of plagiarism after he had heard Harrison's explanation.

He was especially interested in the measurement of air pressure and the ideas outlined by Robert Hooke for recording barometer readings, in 1765 making a special clock for George III which recorded on a chart the changes in barometer readings over a year. This is considered to be the first effective recording barograph, and he was paid £15 per year to maintain it. The next year he made a slightly different version for his own use, which after his death was bought by Luke Howard, who used it for the observations that formed the basis of his pioneering work ' The Climate of London'. He made two gold stopwatches for William Hamilton FRS 1766 at Naples, and in 1769 a watch for Charles Blagden FRS 1772, on whose behalf he ordered an electifying machine from Jesse Ramsden FRS 1786.