Lenses

Spectacles were invented in the Middle Ages 'to remove darkness from the eyes'.  Spectacle makers in the Dutch Republic combined two lenses to create the first 'spyglasses' around 1608.  Within two years, Galileo had used an improved version of the instrument to make the most revolutionary series of observations in the history of astronomy. Half a century later, the microscope was conceived by leading figures like Robert Hooke as a means of 'repairing the defects of the senses'. Contemporaries, in other words, were not mistaken in regarding these revolutionary optical instruments as a direct extension of the art of medicine. All three of these examples derive directlty existing series on Cabinet, dealing with medieval and Renaissance technology, seventeenth-century astronomy, and the early Royal Society.