The compound microscope, which combined an eyepiece and an objective lens, was developed in the early 17th century. It allowed for high magnification and a sharply focussed image. Robert Hooke (1635–1703) was among the first scientists to publish observations of microscopic bodies. Browne was certainly aware of these technological advances. He owned a pair of magnifying glasses and in letters to his son, Edward, he made comments on microscopic observations.