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 in each other, and succeeded in making the first telescope on record.

The principal documents from which the above facts touching Lippershey have been extracted, are to be found in a memoir on the subject by Olbers, printed in Schumacher's Astronomical Annual for 1843.

It was said in the time of Galileo that he had in his possession a telescope by the aid of which he could see the birds flying at Fiesole from the window of his palace in Florence. This story does not in the least detract from the merit of the illustrious astronomer, who not only constructed a telescope for himself, but was the first to direct it heavenwards, and that too by purely theoretical researches; for in spite of all the documents adduced above, there is little or no proof that he had ever seen or heard of the Dutchman's telescope. It is only right, therefore, that the instrument constructed on this principle should be called the Galilean telescope. He afterwards increased its power from four to thirty times, beyond which he could not get with the means at his command. With his imperfect instruments Galileo discovered the satellites of Jupiter, the mountains of the moon, and the spots on the sun, and earned for himself the name of Lynceus, who according to the ancients was one of the Argonauts, possessed of the power of seeing through a wall. Towards the end of his life, when the old man was blind, and the Academy of the Lincei treated his hypotheses with disdain, he would laugh sadly at the name bestowed on him, and the obstinate Academy. Fig. 41 (see next page) shows the path of the rays in a Galilean telescope. The object-glass o is double convex, aond the eye-piece o bi-concave. The image is formed between these lenses, and the eye appears to see it at that point. The States-General complained of being obliged to shut one eye when looking through a telescope, but in 1671 a good