There are also some notices in Marinus of voyages performed along the coast of Africa, between India and Africa, and along part of the coast of India; he particularly mentions one Theophilus who frequented the coast of Azania, and who was carried by a south-west wind from Rhapta to Aromata in twenty days; and Diogenes, one of the traders to India, who on his return after he had come in sight of Aromata, was caught by the north-east monsoon, and carried down the coast during twenty-five days, till he reached the lakes from which the Nile issues. Marinus also mentions a Diogenes Samius, who describes the course held by vessels from the Indus to the coast of Cambay, and from Arabia to the coast of Africa. According to him, in the former voyage they sailed with the Bull in the middle of the heavens, and the Pleiades in the middle of the main yard; in the latter voyage, they sailed to the south, and by the star Canobus. We now arrive at the name of Ptolemy, certainly the most celebrated geographer of antiquity. He was a native of Alexandria, and flourished in the reign of the emperor Marcus Antoninus. In the application of astronomy to geography, he followed Hipparchus principally, and he seems from his residence at Alexandria to have derived much information through the merchants and navigators of that city, as well as from its magnificent and valuable library. His great work, as it has reached us, consists almost entirely of an elementary picture of the earth, (if it may be so called,) in which its figure and size, and the position of places are determined. There is only a short notice of the division of countries, and it is very seldom that any historical notice is added. To this outline, it is supposed that Ptolemy had added a detailed account of the countries then known, which is lost.