Inventory no. 41951 - Former Display Label
?Fake Astrological ASTROLABE of unknown origin
Date uncertain
Unsigned and undated. Gilt brass and silver.
No loose plates. The mater is engraved with lines denoting the cusps of the twelve astrological houses, over which revolves, in place of a more elaborate rete, the circle of the ecliptic. The rim is engraved with a scale of twice twelve equal hours, midnight being at the bottom of the instrument.
The astrologer set the rule to the time of the event of which he intended to cast a horoscope and to the position of the sun in the ecliptic. The intersections of the lines in the mater with the ecliptic would then indicate the degrees of the ecliptic corresponding to the beginning of each of the twelve houses. The position in these of the planets was added from astronomical tables.
The back is engraved with a table of the times of sunset, at intervals of six days, throughout the year.