George Graham, clock and instrument maker, c 1740s.
© Science Museum / Science & Society Picture Library
Engraving by Faber after the painting by T Hudson. Following his apprenticeship with London clockmaker Henry Askem, George Graham (1673-1751), the inventor of the mercurial pendulum, was considered one of the greatest instrument makers of his day. He made various astronomical instruments, and contributed significantly to the advancement of precision timekeeping.