Sign In

A Celestial Rarity

This rare celestial map configured in the shape of a cross, published by Augustin de Lavault in Brussels around 1838 by Librairie Belge Francaise is a mysterious artifact of astronomical science and art from the early 19th century.

The map incorporates text sections divided into four quadrants, each filled with rich textual content in French that describes various astronomical phenomena and the basis for constellation naming. It explains the partition of the celestial sphere into the northern and southern hemispheres and the zodiacal belt, along with detailed accounts of the magnitudes of stars and their positional relationships within their respective constellations.  

The text boxes provide insights into the practical applications of the map. They describe the ecliptic path of the sun through the constellations, the significance of the equinoxes and solstices, and the methods used to categorize and denote the brightness of stars within each constellation. This educational aspect highlights the dual function of the map as both a reference guide and a didactic tool.

Top Left Text Section: The top left section of the map provides a foundational overview of astronomical categorization as understood in the 19th century. It explains how astronomers divided the sky into three major regions: the northern and southern hemispheres, and the zodiacal belt. The stars within these regions were grouped into constellations, often represented by various animals or figures, with a total of 36 in the northern hemisphere, 12 in the zodiac belt, and more in the southern hemisphere. Additionally, it discusses the nature of stars in terms of their fixed positions, constant brightness, and relative distances from Earth, emphasizing their role in aiding the identification of planetary movements. The constellations are preserved with their ancient names, and the brightest stars in each constellation are marked with Greek letters in descending order of luminosity.

Top Right Text Section: The text in the top right corner elaborates on the motion of the Earth in relation to the apparent movement of the sun and stars. It clarifies that the sun, while appearing to move through constellations, is stationary, with the observed motion being a result of the Earth's rotation. The text elaborates on the ecliptic—the path that the sun appears to trace through the zodiac constellations. This segment serves to educate about the relationship between the Earth’s orbital dynamics and the visible arrangements of stars and constellations, particularly highlighting the concept of opposing constellations as the Earth and Sun align with one another throughout the year.

Bottom Left Text Section: In the bottom left, the discussion focuses again on the celestial dynamics involving the ecliptic and the zodiacal belt. This text explains the significance of the ecliptic as the central line around which the zodiacal signs are aligned, each corresponding to a division of the year into twelve months. It describes the practical and symbolic importance of the equinoxes and solstices, detailing their impact on day length and seasonal changes. This segment deepens the viewer's understanding of how celestial movements are synchronized with Earth's seasons and how these were historically used to structure time and agricultural activities.

Bottom Right Text Section: The final quadrant, bottom right, offers a practical guide to observing the night sky, focusing on major constellations visible from the northern hemisphere. It mentions specific stars and constellations such as the Big Dipper (part of Ursa Major), the Little Dipper (Ursa Minor), and how these constellations can be used to locate the North Star (Polaris). The text provides a descriptive guide for tracing imaginary lines across the sky to connect different stars and constellations, aiding in their identification and emphasizing their practical use in navigation and time-keeping.

Each of these sections collectively underscores the educational purpose of the map, merging detailed scientific knowledge with practical guidance for star observation. This blend of academic content with functional application reflects the 19th-century fascination with both understanding and utilizing the night sky for navigation, time-keeping, and exploration.

Rarity

The map is apparently unknown to modern bibliographers.

We note only a reference to the map as entry #2959 in the 1878 Catalogue des ouvrages d'astronomie et de météorologie qui se trouvent dans les principales bibliothèques de la Belgique, by Albert Lancaster (Catalogue of Works on Astronomy and Meteorology Found in the Main Libraries of Belgium).

We find no references to Augustin de Lavault and only scant reference to the Librairie Belge Francaise at the address shown, between 1837 and 1839.