Newtonian telescope Newtonian telescope The Newtonian telescope, also called the Newtonian reflector or just the Newtonian, is a type of reflecting telescope invented by the English scientist Sir Isaac Newton (1642–1727), using a concave primary mirror and a flat diagonal secondary mirror. Newton's first reflecting telescope was completed in 1668 and is the earliest known functional reflecting telescope. The Newtonian telescope's simple design makes it very popular with amateur telescope makers. Newton's idea for a reflecting telescope was not new. Galileo Galilei and Giovanni Francesco Sagredo had discussed using a mirror as the image forming objective soon after the invention of the
Julio Conde death of his brothers Faustino y Mariano in the years 1988 and 1989, Julio, the only nephew successor, continued enlarging even more the figure of the high quality handmade guitar inside and outside our frontiers. At the present time, and from Julio's death in 1995, their sons and his granddaughter, in the same centre, continue the tradition Hermanos Conde, where the careful selection of materials and the quality of the final sound are maintained and continue as a high-priority goal. Julio Conde Julio Conde (Villalba de los Alcores, Valladolid, 1915 - Madrid, 1995) was a spanish luthier trained by his