The renowned French chemist, Berthelot, has given a valuable analysis of the alchemist’s method of treating chemical phenomena. His general conclusion is that the false principles which led the alchemists astray revert back to Plato’s and Aristotle’s philosophical theories regarding the composition of matter. Something similar can be said of astrology. It plays with ideas of its own fabrication with hardly any foundation in reality. The result is almost wholly without value. The greatest astronomer in Babylon, Kidinnu (about 200 B.C.), constructed tables of great accuracy giving the position of the stars. In this work he utilized observations gathered over thousands of years. These ephemerides were also intended as scripture source for reading the fate of men and for determination of the auspicious moment for the commencement of an undertaking. At all events, they placed great revenue and power over souls in the hands of the ruling priesthood. It does not appear that these priests were able to rise to an attempt of a physical explanation as to the nature of the stellar bodies. That was probably also considered dangerous. The stars were deities composed of purer and more refined matter than found on Earth. It were not improbable that the gods would inflict vengeance on the presumptuous one who dared to intrude upon their secrets and pass judgment on their peculiarities. Fortunately, there existed in Greece another tendency in philosophy besides the scholastic and the Platonic-Aristotelian. But this was mainly represented in southern Italy, Sicily, and later in Alexandria. Already the followers of Pythagoras had made important progress toward a solution of the stellar problems. The crowning point was reached by Aristarchos from Samos, who lived in Alexandria about 2100 years ago. He established 1700 years before Copernicus the heliocentric system. It is often said that his work was of little value, as Copernicus nevertheless must do it over again. It is then forgotten that Copernicus himself cites the philosophers of antiquity who expressed theories in agreement with the heliocentric system and expressly states that he was bold enough to advance his hypotheses because so many prominent authorities could be mentioned who favoured them. Copernicus did not dare entirely to break away from the Ptolemaic system, and was inconsistent enough partly to use it in his calculations of the motions of the stars.