assuredly complete their circuit, notwithstanding thecontrary motion of the wheel; and, moreover, thatnearest the centre will perform his journey sooner thanhe who is travelling in the outer channel of the wheel,who, though he move with equal velocity, yet, from thegreater extent of his circuit, will require a longer timefor its completion. It is even so with the planets,which, each in its particular orbit, revolve in a directioncontrary to the motion of the heavens, although, in theirdiurnal motion, they are carried backwards by its rota-tion. The reason why some planets are temperate, somehot, and others cold, appears to he this; that all fire hasa flame, whose tendency is upward. Hence the sunwarms, by his rays, the air above him, wherein Marsmoves, and that planet is therefore heated thereby. Sa-turn, on the contrary, who is near the extremity of theuniverse, and comes in contact with the frozen regionsof the heavens, is exceedingly cold. Jupiter, however,whose orbit lies between those of the two just men-tioned, is tempered by the cold and heat, and has anagreeable and moderate temperature. Of the band com-prising the twelve signs, of the seven planets, and theircontrary motions and orbits, also of the manner andtime in which they pass from one sign into another, andcomplete their circuits, I have set forth all that I havelearnt from authors. I will now speak of the moon’s in-crease and wane, as taught by the ancients. JBerosus,who travelled into Asia from the state or country of theChaldeans, teaching his doctrines, maintained that themoon was a ball, half whereof was luminous, and theremaining half of a blue colour; and that when, in itscourse, it approached the sun ; attracted by the rays andthe force of the heat, it turned its bright side in thatdirection, from the sympathy existing between light andlight; whence, when the sun is above.it, the lower part,which is not luminous, is not visible, from the similarityof its colour to the air. When thus perpendicular to