Tuesday, November 22, 2011

"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.






Tuesday, November 15, 2011

The various and ingenious machines of Captain Agostino Ramelli (16th Century)


Agostino Ramelli was an Italian engineer who significantly contributed to water wheels, mills (for grain and others), cranes, and jacking devices development during 16th century. His treatise “Le diverse et artificiose machine del Capitano Agostino Ramelli” -The various and ingenious machines of Captain Agostino Ramelli- had a great impact in the field of mechanical engineering. About his BIO, he served in the Army of Giacomo de Medici where he took contact with engineering disciplines. After a couple of years he realized about mathematics and geometry as an important tool for engineers and artists, and started his career as inventor.

Captain Agostino Ramelli

Wikipedia has a very poor (¿?) article here about Agostino Ramelli, with a curious reference as a world wide web precursor due to his invention called “book wheel” or “reading wheel” which is basically a device designed to allow one person to read a variety of books in one location, simply turning a huge vertical or horizontal wheel where the books are located.
This treatise is a fine example of the exquisite work of sixteenth-century printers and engravers. Printed in folio format, thus allowing great detail to be placed in the numerous engraved plates, which a total of 195. Another particularity is the fact that was printed in French and Italian.

The... world wide web service precursor? Why don't we ask Mr. Berners-Lee's opinion?

Grain mill

Heavy duty crane example

Military application (deffense breaking)

Self explained... Ramelli has more than 5 different types of screw jack devices in his treatise

Water wheel (human action)

Water wheel (water action)