18th century illustration of the constellations Pegasus and Equuleus

A chart of the constellations of Pegasus and Equuleus (the winged horse and foal), engraved by Johann Christoph Berndt for the celestial atlas 'Mercurii Philosphici Firmamentum Firmianum', named for Thomas's patron, Leopold Anton von Firmian, Archbishop of Salzburg.

Corbinianus Thomas (1694-1767), a Benedictine monk, was Professor of Mathematics and Theology at the University of Salzburg. His star atlas was first published in 1730 at Frankfurt, with a second edition at Augsburg the following year. He used an odd system for nomenclature: Greek letter for the star, Roman numeral for the magnitude and Arabic numeral for the star catalogue reference.