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Astronomy, Diagram, Astrology, Planets, Pro Crisibus Morborum, Zahn, Antique Map, 1696


Johann Zahn (1641-1707) (author)
Pro Crisibus Morborum et Aspectibus Planetarum
[Health As Determined by Planetary Aspects]

from Specula physico-mathematico-historica notabilium ac mirabilium sciendorum]
[Observations of Physical-Mathematical-Historical Harmony and the Wonders of Knowledge]
Johann Christoph Lochner, Nuremberg: 1696
Engraving with some hand color
13.75 x 16 inches, border
15.25 x 18 inches, overall

Circular astrological chart flanked by two tables, set within a decorative classical design in the Baroque taste, and labeled in Latin. The chart apparently was for predicting health (specifically, periods of greater or lesser likelihood of illness) in relation to planetary alignments. It is one of 55 engraved plates from Volume 1 of a richly illustrated three-volume compendium of mathematics and natural history by Johann Zahn, who also authored an important 17th-century work on optics.

Product description continues below.


Two circular inscriptions on either side of the main diagram briefly explain how the Sun, Moon, Saturn, Jupiter, Mars and Venus in “Domo VIII,” the Eighth House, affect health. One of these summarizes the planetary conditions affecting health during the “annis climacteris” (climacteric year), an astrological concept also found in the writings of ancient Greek philosophers. In this belief system, every seventh year of a person’s life was called a climacteric year, and was supposedly a time of increased physical vulnerability. The planet Saturn was said to exert a key influence over these events.

The tables on either side of the chart have columns of numbers corresponding to Motus Menstruus [Monthly Motion], the lunar cycle, and Motus Diurnus [Diurnal Motion], the daily rotation of the earth every 24 hours. The basic divisions of the central diagram include an outer dial labeled in Roman numerals divided into 28 sections, and an inner dial divided into 12 numbered sections corresponding to the signs of the zodiac. In the center, radiating lines labeled “Intercedens” (intervening) and “Indicitivus” (indicative) and “Dies Perfecté Criticus” (literally “perfect daylight”). The engraving has been mostly left uncolored, with a few details highlighted with yellow-orange watercolor.

Johann Zahn was a canon of the Premonstratensian monastery of Oberzell near Würzburg, Germany, author on scientific topics, and inventor. He wrote two major scientific works. Oculus artificialis teledioptricus sive Telescopium (1685) described and illustrated various kinds of optical devices, including the camera obscura, magic lantern, telescopes and microscopes, describing the use of mirrors and lenses to focus and project images. Specula physico-mathematico-historica notabilium ac mirabilium sciendorum (1696) was a three-volume compendium of mathematics and natural history.

Johann Christoph Lochner (1653-1730) was a German publisher and printer of books in Nuremberg.

Inscription upper left circle: Crises bonae [planetary symbols] in Horoscopo vel Domo VIII initio morbi: vel ab ÿsdem in progressu fortunato. [Rough translation: Good period. The Moon…the Sun, Jupiter and Venus in the horoscope of the 8th House initiates illness: even as the very same fortune advances.]

Inscription upper right circle: Crises malae [planetary symbols] vel [Mars] ad initiummor si tempore Eclipsis in Annis climactericis item [Saturn] et [Mars] aspectus tempore morbi in Horoscopo aut Domo VIII. [Rough Translation: Bad period. One observes a period of illness if the Moon…Saturn or Mars are near the beginning of the time of Eclipsis in the climacteric year, likewise if Saturn and Mars are in the horoscope of the 8th House.]

Inscription upper right margin: Tom. 1. pag. 57. [Book 1, page 57]

Condition: Generally very good with the usual overall light toning and wear.   Vertical center fold, as issued.


“Johann Christoph Lochner.” British Museum. (28 April 2021).

“Johann Zahn.” Wikipedia. 12 April 2021. (28 April 2021).

“Lot 410, 2017. Live Auction 14298 The Giancarlo Beltrame Library of Scientific Books, Part III.” Christie’s. 25 April 2017. (28 April 2021).

Additional information


17th Century