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A Dictionary of Greek and Roman biography and mythology (ed. William Smith) 6 6 Browse Search
Strabo, Geography (ed. H.C. Hamilton, Esq., W. Falconer, M.A.) 2 2 Browse Search
Samuel Ball Platner, Thomas Ashby, A Topographical Dictionary of Ancient Rome 2 2 Browse Search
Knight's Mechanical Encyclopedia (ed. Knight) 2 2 Browse Search
Appian, The Foreign Wars (ed. Horace White) 1 1 Browse Search
Pliny the Elder, The Natural History (ed. John Bostock, M.D., F.R.S., H.T. Riley, Esq., B.A.) 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 276 BC or search for 276 BC in all documents.

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Knight's Mechanical Encyclopedia (ed. Knight), A. (search)
my (see Whewell, I. 201). These armils are divided into parts of sixths of degrees (10′). The reading was stated in parts of the circumference. Thus, Eratosthenes stated the interval between the tropics to be 11/83 of the circumference. Ptolemy used a part of a circle, a quadrant. It is supposed that Eratosthenes suggested to Ptolemy Euergetes the construction of the large armillae, or fixed circular instruments which were long in use in Alexandria. Eratosthenes of Cyrene was born B. C. 276, and left Athens at the invitation of P. Euergetes, who placed him over the library in Alexandria, where he remained till the time of P. Epiphanes about B. C. 196. He is celebrated for his attempt to measure the magnitude of the earth. He discovered the obliquity of the ecliptic, which he made to be 23° 51′ 20″. He ascertained that Syene in Upper Egypt (lat. 24° 10′N.) was in the tropic, a vertical gnomon casting no shadow at noon on the day of the summer solstice, and thence determined
Knight's Mechanical Encyclopedia (ed. Knight), O. (search)
France, measured with an instrument of this kind, in 1550, a degree of the meridian between Paris and Amiens, and found it to be 303 toises less than Picard afterward found it to be. It is supposed that the revolutions of the wheel were noted by striking on a bell. The measurement of a degree of latitude has been made and recorded not less than fourteen times in the last 1,000 years. Its length varies in different countries, as the facts show and theory had supposed. Eratosthenes, B. C. 276, attempted the measurement of the size of the earth, by ascertaining the distance between Alexandria and Syene, the differences of latitude between which places he had found to be 1/50 of the earth's circumference. Some previous measurements are mentioned under armil (which see). Hipparchus of Nicaeea in Bithynia, 162 B. C., laid down a map by the determination of the latitude and longitude of places. A degree was measured on the shores of the Red Sea by the Khalif al Maimoun, the son of