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
Hermanos Conde themselves ""Sobrinos de Domingo Esteso Conde Hermanos"" (Esteso's Nephews, Conde Brothers) or ""Hermanos Conde Sobrinos de Domingo Esteso"" (Conde Brothers, Esteso's Nephews). Mariano Sr. later established his own shop close to the Royal Theatre, calling it "Conde Hermanos Sucesores Sobrinos de Esteso". His two sons, Felipe, born in 1957 and Mariano Jr., born 1959, began their apprenticeship with their father and uncle Faustino when they were about 15 years old. Faustino died in 1988 and Mariano Sr. in 1989. Felipe and Mariano Conde (sons of Mariano Conde Sr.) manufactured flamenco guitars in their workshop at Felipe V St. nº 2