Classic flat astrolabe. Limb divided up into 360º without figures, and in two series, from I to XII hours in Roman numerals. The five plates or tympans correspond to the following latitudes: 52º Parisian (48º), 45º, 42º and 40º. On the reverse side there is a calendar showing the 12 signs of the zodiac and the ecliptic longitude of the Sun for every day of the year. This particular piece is incomplete, as it is lacking its spider, alidade, axis and pin.