Sir William Watson, M.D., was the son of a respectable tradesman in St. John-street, Smithfield, and was born in 1715. He was educated at Merchant Taylors’ school, and in 1730 was apprenticed to Mr. Richardson, an apothecary in the city. In 1738 he commenced business for himself. His skill, activity, and diligence in his profession, soon distinguished him among his acquaintance, as did his taste for natural history and his knowledge of natural philosophy among the members of the Royal Society, of which he was elected a fellow in 1741. He devoted much attention to botany and electricity, and his writings on these subjects are numerous, original, and valuable. His researches in electricity were of so interesting a nature that they gave him the undisputed lead in this branch of philosophy, and were the means not only of raising him to a high degree of estimation at home, but of extending his fame throughout Europe. At that time it was no small achievement in electricity to be able to fire spirits of wine.
He was the first in England who effected this, and he afterwards fired inflammable air, gunpowder, and inflammable oils by the same means. He was the first to note the different colour of the spark as drawn from different bodies, and to prove that electricity suffered no refraction in passing through glass; that the power of electricity was not affected by the presence or absence of fire, since the sparks were equally strong from a freezing mixture as from red-hot iron; that flame and smoke were conductors of electricity, and that the stroke was as the points of contact of the non-electrics on the outside of the glass. This last investigation led to the coating of phials, in order to increase the power of accumulation, and eminently qualified him to be the principal actor in the celebrated experiments made on the Thames and at Shooter’s-hill in 1747 and 1748, in one of which the electric circuit was extended to four miles in order to prove the velocity of its transmission. He received the Copley Medal in 1745 for his "surprising discoveries in electricity exhibited in his late experiments." Mr. Watson’s house in Aldersgate-street became the resort of the most ingenious and illustrious experimental philosophers that Europe could boast. Several of the nobility attended to witness his experiments; there it was that amongst a large concourse of people the duke of Cumberland, recently returned from Scotland, took the shock with the point of the sword with which he had fought the battle of Culloden; and on one occasion George the Third, when prince of Wales, honoured him with his presence.
The university of Halle, to mark its sense of his merits, created him doctor of medicine by diploma, bearing date 6th September, 1757; and the university of Wittemberg, about the same time, conferred on him a similar honour. He now removed from Aldersgate-street to Lincoln’s-inn-fields. Having been disfranchised from the Apothecaries' company, he commenced practice as a physician; and after the usual examinations was admitted a Licentiate of the College of Physicians 22nd December, 1759. In October, 1762, Dr. Watson was elected physician to the Foundling hospital, which office he retained during the remainder of his life. As Dr. Watson lived in intimacy with the most illustrious and learned members of the Royal Society, so he was himself one of its most active members, and ever zealous in promoting the ends of that institution. For many years he was a frequent member of the council, and during the presidentship of Sir John Pringle was elected one of the vice-presidents. On the 30th September, 1784, on the recommendation of the President, he was elected, and on the 18th October next ensuing actually admitted a Fellow of our College. He was Censor in 1785 and 1786. He was knighted in 1786, but did not long survive that honour, dying on the 10th May, 1787.
Sir William Watson’s character was affectionately and accurately drawn by his warm and constant friend, Dr. Garthshore. "As a physician," writes he, "his humanity, assiduity, and caution were eminently conspicuous; and his exact observance of the duties of social politeness must ever be remembered with pleasure by all those who enjoyed the happiness of his acquaintance. The smile of benignity was always displayed on his countenance; he invariably continued the general, the ready, and the obliging friend of mankind; he was respectful to the elder and superior, encouraging to the younger, and pleasant and easy to all with whom he had any intercourse. The same affability and good humour which adorned his character in public life was preserved also in the bosom of his family, and endeared him to all those who were more immediately around him."* Sir William Watson’s portrait by Abbot is at the Royal Society. It was engraved by Ryder. He was the author of—
Experiments and Observations on Electricity. 8vo. Lond. 1745.
Account of a Series of Experiments instituted with a view of ascertaining the most successful Method of inoculating the Smallpox. 8vo. Lond. 1768.
[(1) See Pulteney’s Biographical Sketches]