The information we have concerning the Ionic School of Philosophers, of which school Thales is reputed to have been the founder, does not give us any satisfactory evidence that attempts were made by any of their number at a material representation of their astronomical or geographical theories. They were content, in the main, with mere philosophical or cosmical speculations. The statement, therefore, that Thales himself constructed a celestial globe, on which to represent his notion of the crystal sphere, is not well authenticated.[30] While not assured to us by any positive statement, there appears to be good reason for believing the astronomer Eudoxus of Cnidos (409-356 B. C.) made use of a celestial globe on which to represent certain astronomical theories which he entertained.[31] He traveled in Egypt in his later life, where he carried on his studies, and where he seems to have learned the construction of star catalogues. On his return to his own country he is reported to have undertaken the representation of the several constellations known to him, on a celestial sphere. The astronomical poem of Aratus (fl. 270 B. C.),[32] so frequently cited and copied in following centuries, is considered to be a description of the constellations according to Eudoxus. In the Royal Museum of Naples there may be found a large marble celestial globe, 65 cm. in diameter (Fig. 7), which the mythical Atlas bears on his shoulders, the statue itself being 1.86 m. in height, resting on one knee.[33] This very interesting and artistic object was transferred to Naples museum from the Farnese Palace in Rome, hence is generally referred to as the Atlante Farnesiano. Forty-two constellations are represented on its surface (Fig. 8), and the five wanting, including Ursa Major and Ursa Minor, probably owe their absence to the obliteration which time has brought about. From the position of the several constellations, relative to the intersecting points of the ecliptic with the equator, it is thought that it must have been constructed at least three hundred years before the Christian era. It seems therefore to date from about the time of Eudoxus, being then the oldest extant globe. [Illustration: Fig. 7. Atlante Farnese, ca. 200 B. C.] [Illustration: Fig. 8. Atlante Farnese Constellation Figures.]