For a fuller account of this method, see Gow, _Short History of Greek Mathematics_, pp. 127 sqq.; and Milhaud, _Science grecque_, p. 99. Footnote 35: R. P. 188. Footnote 36: The real meaning of ἁρπεδονάπτης was first pointed out by Cantor. The gardener laying out a flower-bed is the true modern representative of the “harpedonapts.” Footnote 37: See Milhaud, _Science grecque_, p. 103. Footnote 38: The word πυραμίς is often supposed to be derived from the term _piremus_ used in the Rhind papyrus, which does not mean pyramid, but “ridge.” It is really, however, a Greek word too, and is the name of a kind of cake. The Greeks called crocodiles lizards, ostriches sparrows, and obelisks meat-skewers, so they may very well have called the pyramids cakes. We seem to hear an echo of the slang of the mercenaries that carved their names on the colossus at Abu-Simbel. [Sidenote: Babylonian astronomy.] XII. The other source from which the Ionians directly or indirectly derived material for their cosmology was the Babylonian astronomy. There is no doubt that the Babylonians from a very early date had recorded all celestial phenomena like eclipses. They had also studied the planetary motions, and determined the signs of the zodiac. Further, they were able to predict the recurrence of the phenomena they had observed with considerable accuracy by means of cycles based on their recorded observations. I can see no reason for doubting that they had observed the phenomenon of precession. Indeed, they could hardly have failed to notice it; for their observations went back over so many centuries, that it would be quite appreciable. We know that, at a later date, Ptolemy estimated the precession of the equinoxes at one degree in a hundred years, and it is extremely probable that this is just the Babylonian value. At any rate, it agrees very well with their division of the celestial circle into 360 degrees, and made it possible for a century to be regarded as a day in the “Great Year,” a conception we shall meet with later on.[39] Footnote 39: