Museo Galileo
Virtual Museum
Johann Wiesel

A pupil of the Capuchin Father Antonius Maria Schyrleus de Rheita (1604-1660), Wiesel made telescopes, microscopes, and - following the instructions of Chérubin d'Orléans (1613-1697) - binocular telescopes. In 1654, he started a correspondence with Christiaan Huygens (1629-1695). Reversing the configuration used in Italian telescopes, Wiesel placed the eyepiece in the large tube and the objective in the small tube. Wiesel's telescopes were introduced in England c. 1650. The English makers adopted his design, but with a major alteration: from the late seventeenth century onward, English terrestrial telescopes were fitted with the compound eyepiece invented by Giuseppe Campani (1635-1715).