1715-1787

English physicist and botanist remembered primarily for his studies of electricity, especially those conducted with the Leyden jar. Watson improved this device both by lining it with lead foil (suggested by John Bevis) and thinning the glass. His experiments suggested, counter to effluvial theory, that electricity was a single fluid. Benjamin Franklin concurrently developed a similar theory, though in greater detail, which emerged as the standard view of electrical phenomena by the end of the eighteenth century.