“ If the sun is found in the northern constellations, which are Aries, Taurus, Gemini, Cancer, Leo and Virgo, subtract the distance of the sun from the ecliptic from its height over the celestial horizon and that equals the height of the ecliptic over the celestial horizon. ”

“ Through knowledge of the times one is able to determine other unknowns, as was seen in section 200. One who knows the measure of arc BC or angle BEG can determine, through use of the tables, how many units are needed to function as a secant for that angle, and after the measure of the maximum sine is determined, which is line BE, or half the diameter of the Earth, it can now be seen that the height of the mountain is the difference between the maximum sine and the secant line. ”

“ For example, in the figure in the previous section, one may have seen that before midday the last point on the circumference touched by the shadow is E, and after midday the first point touched is C. With these two point the line CE is drawn and bisected by line HKD, as was done in the previous section, and this is the direction of the celestial meridian. If one desires he can make many concentric cycles around the center, each within the other [to get results closer to the moment of midday itself] , observing when the shadow touches them before midday and after. ”