Telescope

An optical instrument assisting the eye or camera in viewing or photographing distant objects, magnifying the celestial bodies, and concentrating a larger beam of light to render the image more distinct. Some ancient references suggest that it was known to the Greeks and Romans. In the Pyramid is found evidence that at some period the Egyptians had a form of reflecting telescope. Refracting telescopes were first made in Holland in 1608. Hearing about them, Galileo made one for himself and in 1620 began his experiments. The earliest known reflecting telescope was that perfected by James Gregory of Edinborough in 1663.