Robert Hooke FRS (; 18 July 1635 – 3 March 1703) was an English polymath active as a scientist and architect, who, using a microscope, was the first to visualize a micro-organism. An impoverished scientific inquirer in young adulthood, he found wealth and esteem by performing over half of the architectural surveys after London's great fire of 1666. Hooke was also a member of the Royal Society and since 1662 was its curator of experiments. Hooke was also Professor of Geometry at Gresham College.