↑ The History of the Telescope, by Henry C. King, page 30 ↑ The History of the Telescope By Henry C. King, page 30 ↑ Light Years: An Exploration of Mankind's Enduring Fascination with Light By Brian Clegg ↑ Fred Watson, Stargazer (page 55) ↑ galileo.rice.edu The Galileo Project > Science > The Telescope by Al Van Helden ↑ The History of the Telescope By Henry C. King, page 27, "(spectacles) invention, an important step in the history of the telescope" ↑ Osservatorio Astronomico di Bologna - TELESCOPES ↑ Osservatorio Astronomico di Bologna - TELESCOPES "The request however was turned down, also because other spectacle-makers had made similar claims at the same time." ↑ "The Hague discussed the patent applications first of Hans Lipperhey of Middelburg, and then of Jacob Metius of Alkmaar... another citizen of Middelburg, Zacharias Janssen had a telescope at about the same time but was at the Frankfurt Fair where he tried to sell it" galileo.rice.edu The Galileo Project > Science > The Telescope by Al Van Helden ↑ Van Helden (1977, p.40; 1985, p.65), Drake (1978, p.138) ↑ A people's history of science: miners, midwives, and "low mechanicks" By Clifford D. Conner ↑ A people's history of science: miners, midwives, and "low mechanicks" By Clifford D. Conner