Astronomical chart, scientific calendar. (Machine-translation by Google Translate, not legally binding)

摘要

An astronomical letter, scientific calendar, characterized essentially by being composed of a set of coupled elements, namely: a circular crown contour, or similar, graduated in days and months, with the signs of the Zodiac and seasons, a central disk or similar, rotating on the previous contour, graduated in its periphery in hours and fractions of hour, carrying this disc or similar, in its central part, emptied or marked, an ellipsoidal contour, through which the bottom of the set is seen, the which is constituted by the representation, more or less detailed, of the celestial vault, with its constellations, the ecliptic and corresponding vector radii. (Machine-translation by Google Translate, not legally binding)