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ssible, the latitude of Alexandria; but it would lead us far from the object of our work, if we were even briefly to mention his discoveries in the science of pure astronomy. We must confine ourselves to those parts of his discoveries which benefitted geography, either directly or indirectly. After having, as successfully as his means and the state of the science would permit him to do, fixed the position of the stars, he transferred the method which he had employed for this purpose to geography: he was the first who determined the situation of places on the earth, by their latitudes and longitudes, with any thing like accuracy. The latitude, indeed, of many places had been fixed before; and the means of doing it were sufficiently simple and obvious: but with respect to some general and safe mode of ascertaining the longitudes, the ancient philosophers before Hipparchus, were ignorant of it. He employed for this purpose the eclipses of the moon. After having ascertained the latitudes and longitudes of a great many places, he proposed to draw up a catalogue of terrestial latitudes and longitudes, but this he was not able to accomplish: he had set the example, however and it was followed by subsequent astronomers. He fixed on the Fortunate Islands, which are supposed to be the Canaries, for his first meridian. His principal works most probably were destroyed in the conflagration of the Alexandrian library. His catalogue of the stars is preserved in the Almagest of Ptolemy; and his commentary on Aratus and Eudoxus is still extant. Such is a brief sketch of the advantages which geography, as founded on astronomy, derived from the labours of Hipparchus. We possess little information respecting his ideas of the form of the earth, or the relative position or extent of the different quarters and countries on the surface of the globe. He seems to have been the first who conceived the idea of a southern continent, uniting Africa and India: he had evidently some information, though very vague and erroneous, of India, beyond the Ganges. On the east coast of Africa, his knowledge did not extend beyond Cape Guardaferi. On the whole, geography is more indebted to him for his discoveries in astronomy, and, above all, for his setting the example of carefully ascertaining facts, and not indulging, so much as his predecessors had done, in conjectures and hypotheses, than for any actual discoveries or advances he made in it. The eulogium w
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