Sidereus Nuncius
The first telescopes appeared in the Netherlands in 1608 when Middelburg spectacle-maker Hans Lippershey tried to obtain a patent on one. By 1609 Galileo had heard about it and built his own improved version. He probably was not the first person to aim the new invention at the night sky but his was the first systematic (and published) study of celestial bodies using one. One of Galileo's first telescopes had 8x to 10x linear magnification and was made out of lenses that he had ground himself. This was increased to 20x linear magnification in the improved telescope he used to make the observations in "Sidereus Nuncius".
Mount Wilson Observatory
For the 60-inch telescope, George Ellery Hale received the mirror blank, cast by Saint-Gobain in France, in 1896 as a gift from his father, William Hale. It was a glass disk 19 cm thick and weighing 860 kg. However it was not until 1904 that Hale received funding from the Carnegie Institution to build an observatory. Grinding began in 1905 and took two years. The mounting and structure for the telescope was built in San Francisco and barely survived the 1906 earthquake. Transporting the pieces to the top of Mount Wilson was an enormous task. First light was December 8, 1908. It was at the time the largest operational telescope in the world. Lord Rosse's Leviathan of Parsonstown, a 72-inch (1.8-meter) telescope built in 1845, was, by the 1890s, out of commission.