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Richard Hakluyt, The Principal Navigations, Voyages, Traffiques, and Discoveries of the English Nation 22 22 Browse Search
Harper's Encyclopedia of United States History (ed. Benson Lossing) 5 5 Browse Search
M. W. MacCallum, Shakespeare's Roman Plays and their Background 3 3 Browse Search
Knight's Mechanical Encyclopedia (ed. Knight) 2 2 Browse Search
James Russell Lowell, Among my books 2 2 Browse Search
Robert Underwood Johnson, Clarence Clough Buell, Battles and Leaders of the Civil War. Volume 4. 1 1 Browse Search
Southern Historical Society Papers, Volume 30. (ed. Reverend J. William Jones) 1 1 Browse Search
George Bancroft, History of the United States from the Discovery of the American Continent, Vol. 2, 17th edition. 1 1 Browse Search
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Browsing named entities in Knight's Mechanical Encyclopedia (ed. Knight). You can also browse the collection for 1591 AD or search for 1591 AD in all documents.

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Knight's Mechanical Encyclopedia (ed. Knight), L. (search)
amera-obscura about this time. Dr. Dee says (1570) that perspective glasses will enable a commander to ascertain the strength of an enemy's forces; referring apparently to an optical instrument then in use. Leonard Digges (about 1571) appears to have been able, by proportional glasses duly situate, to discover things afar off, read letters and inscriptions on coins at a distance, and tell what was passing seven miles off. Such is the claim in his son's book, second edition, published in 1591. Jansen (about 1608), a spectacle-maker of Middleburg, Holland, was struck by the effect of a concave and a convex lens held in the proper relation and distance. For the purpose of observation, he fixed the glasses on a board in proper position, and afterwards in a tube. He seems to have considered it interesting but not valuable, and Prince Maurice of Nassau became possessed of it. Lippersheim, also of Middleburg, seems to have been concerned in it in some way. Another claimant of
Knight's Mechanical Encyclopedia (ed. Knight), T. (search)
ascertain the strength of an enemy's forces, referring apparently to an optical instrument then in use. Baptista Porta said: If you properly combine a concave and a convex lens, you will see distant and near objects larger and clearer. Digges states that by an arrangement of mirrors and transparent glasses the image of a small object at a distance may be so augmented as to be brought apparently near to the observer. The matter is restated in a second edition of his works, published in 1591. Toward the middle of the seventeenth century, Borelli, a Dutch mathematician, interested himself in determining the question of inventorship, and decided in favor of Jansen and Lippersheim, spectacle-makers of Middelburg, Holland, about 1590. Galilco, hearing of the principle of the new wonder, constructed one in 1509, magnifying four times, a second magnifying seven times, and then one magnifying thirty-two times. It is only fair to give another account, for which we are indebted to