4to (197 x 148 mm), pp 15 [1], with woodcut Jesuit device on title, 5 woodcut diagrams in text, and one double-page engraved plate; some insignificant spotting and light marginal waterstain, a very good copy in boards. £6000
First edition of this essay on the formation the rainbow and the reflection and refraction of light. The subject was the topic for a disputation at the Collegio Romano. Grassi had taken over from Christoph Grienberger writing and conducting the Problemata, formal scientific debates each on a given topic, as above.
Orazio Grassi (1590-1654) was a Jesuit architect, sculptor, astronomer, and mathematician. He is mostly known for his polemics with Galileo concerning the nature of comets; his Libra astronomica (1618) provoked Galileo into writing Il saggiatore. Actually in the dispute with Galileo it was Grassi, who believed comets to be real objects in space, who was nearer the truth than Galileo.
'On the controversial and scientific plane, Galileo will find Grassi a tough opponent... On the scientific plane, the counterhypothesis [of Galileo] on the nature of comets is confuted by a whole range of refutations of Galileo's interpretative model, which he based on the difference between the physical supports of the rainbow phenomenon and those of other phenomena of solar light reflection. Father Grassi is an expert in the field of optics; he had already published, in 1618, a book entitled 'Disputatio optica de iride' (Redondi, Galileo: heretic).
Riccardi I 628.1 (with incorrect publication date); Sommervogel III 1684 n 1; OCLC: Loyola (Chicago), Harvard, and Wisconsin
GBP 6000.00
This item is listed on Bibliopoly by W. P. Watson Antiquarian Books; click here for further details.