Astrolabe Catalogue

astrolabe, inventory number 42680 from Paris, ca. 1670
thumbnail for astrolabe (front), inventory number 42680 from Paris, ca. 1670
thumbnail for astrolabe (back), inventory number 42680 from Paris, ca. 1670
thumbnail for astrolabe (rete front), inventory number 42680 from Paris, ca. 1670
Dateca. 1670
MakerPierre Sevin
Inventory no.42680
AcquisitionPresented by J. A. Billmeir in 1957

The design of this astrolabe reflects the importance of astrology for makers and users of such instruments. On the single plate, engraved for 49° (Paris), the maker, Pierre Sevin, has engraved the twelve lines representing the horoscopic house divisions. The rete, in turn, has been reduced to simply an ecliptic band and five stars, making it easier to read the positions of the zodiac that correspond to the boundaries between the horoscopic house.

The astrologer would set the alidade to a particular time, for example 9:00 am, according to the equal hour divisions around the limb. Then he would rotate the rete until the sun's position in the zodiac was directly under the front edge of the limb. At that point, the astrologer would read the house divisions directly from the ecliptic where the lines crossed under the ecliptic band.

It was not uncommon to find the horoscopic houses engraved on astrolabe plates. What sets this instrument apart is the correspondingly simple rete design and the absence of other plates.

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Throne, Ring and Shackle

The throne is of the simple type made of brass attached with integrated base made of brass and has a simple, round cross-section ring made of brass and omega type shackle made of brass . More information


The back contains 0 scales. The universal on the back contains 2 scales. More information

Rete, Nut & Bolt

The rete contains 5 stars. The zodiac on the rete is labelled: ♈ , ♉ , ♊ , ♋ , ♌ , ♍ , ♎ , ♏ , ♐ , ♑ , ♒ , ♓ .
The rete is attached using a nut & bolt. Nut is affixed to the rule on the back of the instrument.. More information

Rules & Alidades

Type Details
RegulaDouble-ended, counter-changed. Missing the cursor for use with the de Rojas projection on the back..
AlidadeDouble-ended, counter-changed.
More information


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