Telescopes were being made in considerable numbers in Holland about 1610, and were much improved by Galileo, Kepler and other scientists. This is Sir Isaac Newton's (1642-1727). It is a reflecting telescope, the image being viewed through a compound eye-piece, placed at the side. It magnified from 50 to 800 times, according to the size of the parabolic mirror. The mounting is of the Equatorial type.