43

Christopher Clavius (1538-1612)

Novi Calendarii Romani Apologia.

Rome: Apud Sanctium & Soc., 1588.
First edition, quarto, with IHS emblem to title; bound in later half parchment and paste paper boards; old stamp to verso of title; with circa 1840 bookplate of Carlo Carel bookseller and bookbinder of Novara, Italy inside front board; some water staining to contents; 8 1/4 x 6 in.

Pope Gregory (of Gregorian Calendar fame) needed someone to get in front of the public relations blowback after his calendar reforms were instituted, and originally turned to members of Luigi Lilio's family to turn out a book in support of the changes. Lilio was the primary chronologist behind the reform, and the Pope was trying to repay his family for Lilio's work. He died in 1576, before the new calendar was put into place. Unfortunately, no such publication was forthcoming. Clavius stepped up and came out with the present title.

"Clavius complied with the Pope's wishes and wrote and published his Novi Calendarii Romani Apologia, Rome 1588, which would become the first of a series of texts explaining and defending the calendar reform. The latter was necessary because the reform was not only attacked on religious grounds by numerous Protestants, but also on mathematical and astronomical grounds by such leading mathematicians as François Viète and Michael Maestlin. Over the years Clavius wrote and published several thousand pages defending and explicating the Gregorian calendar reform and it is this work that has linked him inseparably with the calendar reform and not his activities in the commission." (Quoted from the Renaissance Mathematicus blog of 24 February 2016; https://thonyc.wordpress.com/2016/02/24/christoph-and-the-calendar/)

  • Notes: Ex libris Professor, Astronomer, Historian & Bibliophile Owen Gingerich.
  • Condition: a-k4, A-3D4.

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