Special Collections
Book of the Month, July 2010
Tychonis Brahe Dani, Astronomiae Instauratae Progymnasmata
Tycho Brahe
Frankfurt: Gottfried Tampach, 1610
[DeM] M [Brahe] SSR
Tycho Brahe (1546-1601) was a Danish astronomer famed for his accurate measurements of the solar system, enabled by new precision instruments which he invented. His Astronomiae Instauratae Progymnasmata does several important things. It describes Brahe’s observations of the supernova in Cassiopeia of 1572-74, which by establishing that the supernova was further away than the moon broke completely from the traditional Aristotelean view of the heavenly spheres. The book further describes the new metal instruments, mounted on sturdy supports, developed and used by Brahe, which enabled un unprecented degree of precision, to within an arc minute – an improvement which made it possible to refine the Copernican system. It states his theories of solar and lunar movement, the most advanced and accurate yet developed, and it provides a catalogue of the positions of 777 fixed stars.
Brahe began the book, intended as the first volume of a trilogy, at his observatory in Uranienborg. It remained unfinished at his death and was completed by Johannes Kepler (1571-1630), who was Tycho Brahe’s assistant 1600-01 and subsequently succeeded him as imperial mathematician, with the responsibility to complete his unfinished work. The book was first published in Prague in 1602. The edition featured here is largely a reprint, with the title page, preliminaries and first leaf of the text reset and the errata, listed on the final leaf, corrected.
This copy is one of several early astronomical works from the library of the mathematician and mathematical historian Augustus De Morgan (1806-1871). It is also one of several books in the De Morgan Library previously owned by Frederick North, fifth Earl of Guilford (1766-1827), whose extensive library was sold at auction by Evans from 1828 to 1831; North’s stamp (a Gothic capital ‘G’ surmounted by a crown within a circle) is on the title page.
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