“Māshā’allāh said: If you wished to know the variation of the season with respect to the diverse things of the corruptible world, know the signs of the heavy planets (namely, whether they are hot or cold)……In short, know that the heavy planets, if they were in the direction of any of the regions, they will signify dryness and the sterility of the earth; but if they were elongated from it, they will signify a multitude of rains. By ‛nearness’ I want it to be understood that they are in northern signs, and by ‛distance,’ in southern ones.”
“The Head is said to be rising, and its Tail falling, and the signs which the scholars call ‛the concealed’ are from Leo to Capricorn (and it is the region of falling), and from Aquarius to Cancer is the region of rising.
So, look: for if the Moon was in the region of rising, increasing in calculation, then one who buys at that time will buy with expensiveness, and an increase over the price it is worth. And if the Moon was in the region of falling, and she is decreasing in calculation, then what he buys at that time he will buy with cheapness, and less than the price it is worth.”