Novae theoricae planetarum, 16th Century

 

 

I found this manuscript –has an amazing set of volvelles- at Penn Libraries , online available with tag LJS 64. The work is titled “Theoricae novae planetarum”, by 15th-century Austrian astronomer Georg von Peurbach, who taught at the universities in Padua and Ferrara. 

The diagrams demonstrate increasingly complex planetary motion (at least for 15^th Century). The Theoricae Novae was an attempt to present Ptolemaic astronomy in a more elementary and comprehensible way. The book was very successful, replacing the older Theoricae Planetarum Communis as the standard university text on astronomy.

Von Peurbach was very precise taking in account 15th Century astronomy resources & instruments: In 1457 he observed an eclipse and noted that it had occurred 8 minutes earlier than had been predicted by the Alphonsine Tables, the best available eclipse tables at the time. He then computed his own set of eclipse tables, the Tabulae Eclipsium (remained highly influential for many years).

About this codex provenance, was formerly owned by Francesco Rolandi of Turin, teacher of mathematics (There is an inscription dated 1655, inside upper cover). After Francesco Rolandi, books had other owners but was finally sold by William Patrick Watson Antiquarian Books (London), cat. 7 (1996), no. 79, to Lawrence J. Schoenberg and Barbara Brizdle, 2011. (link to their manuscript initiative provided).

Spanish cryptography, 16th Century

Original title for this codex is "Discursos de la cifra", and is basicly a complete treatise on cryptography, including technical description of different methods for enciphering and deciphering using tables, volvelles, movable sleeves, and grilles. Codex was written by an unknown (at least for me so far but my investigation is still on progress) cryptographer in the service of Martin de Cordova, viceroy of Navarre, and dedicated to Juan Fernandez de Velasco, Condestable de Castilla, a Spanish official who held also government posts in Italy, under domination of Spain in that age.

Delicious poem that serve as a preface for first volume: In this borrowed life/ where good life is the key/ the one that is saved knows/ that the other knows nothing.

This codex is complex, because it's composed of two different books or treatises. Cryptography is the second volume. The first is more theoretical and describes ciphers based on subjects such as arithmetic, non-Roman alphabets (Greek, Hebrew) and writing systems (Egyptian, Chinese, Japanese, the writing of Indians of New Spain), astrology, musical notation, geography, currency, orthography, armorials, emblems, and enigmas.

Codex was sold by Martayan Lan -New York office- in Sept. 2001 and donated to the Pennsilvania University by Lawrence Schoenberg, an active philanthropist founder of the computer firm AGS.

"The Emperor’s Astronomy" (16th Century)

The “Emperor’s Astronomy” (Petrus Apianus, 1495-1552) is one of the great masterpieces of sixteenth-century printing, and also one of the top-ten in my personal digital collection. I found the codex a couple of months ago, when I was looking for “volvelles” (or wheel chart, which is a paper slide chart with rotating parts used mainly in ancient astronomy treatises, introduced by Persian astronomer Abu Rayhan Biruni).

I’ll not extend on Petrus Apianus BIO, Wikipedia has a relatively detailed article here. As remarkable fact, Apianus became a favourite scientific of Emperor Charles V through his work and produced also some well known treatises like the “Cosmographicus liber” and other works with variations and studys of Pascal’s triangle, collections of volvelles, and the first known depiction of Bedouin constellation.

Regarding the “Emperor’s Astronomy”... Most of the Volvelles in the codex are used –based on Ptolemaic system- to provide a remarkably accurate graphical calculation of a planet’s position. There is even one for calculating the longitude of Mercury, which contains nine printed parts plus a complex hidden infrastructure to allow movement around four separate axes. Throughout the initial part of his book, Apianus gives detailed instructions for the operation of the volvelles, using as his examples the birth dates of the Holy Roman Emperor Charles V and  his brother Ferdinand I, the dedicatees. But the most curious volvelle is used… for finding the hour of conception from the time of birth and the phase of the moon!!

The second part of the Astronomicum Caesareum deals primarily with lunar eclipses and five comets observed by Apianus in the 1530s. One of them is the one now known as Halley’s Comet. There are 93 known survived copies of this treatise around the world. In 1985 a copy of the Astronomicum Caesareum was auctioned for 80,000 dollars.