MARCHELLI, Giovanni. Trattato del Compasso di Proporzione.Milano, Giuseppe Galeazzi, 1759

8vo, mm. 175x115; Contemporary full vellum binding with squares, gilded titles and rules on the spine, blue edges; pp. XXII, 352, [16]. Titlepage in red and black with nice printer’s device, woodcut initials and ornaments. Wide copper plate out text, mm. 400x500. Stamp of anciernt owner: Cap. L. Bertolotto, Prof. di Nautica.

First and only edition. Important work, written by the Genoese Jesuit for use by its students at the Jesuit College of Milan, which explains in detail how to build the famous instrument invented by Galileo. Slight sihn of foxing, good specimen. Riccardi: “Contiene la descrizione e l'uso del compasso Galileiano. Ritiene l'A. che possa riuscire utilissimo all'insegnamento delle matematiche il cominciare l'istruzione de' giovinetti dalla spiegazione dell'uso di questo geometrico apparato.” The work is a valuable source on the use of scientific instruments in the education of Jesuits: the text shows a thorough understanding of the Galileo compass, and it is noteworthy that this invention is so candidly celebrated by a Jesuit. The large table engraved, in which they outlined five figures, contains patterns for the construction of the compass and indicates very precisely where the lines of the seven proportional scales and the arch of setting circle must be engraved. Exemplary belonged to the famous Captain of Camogli Lazzaro Bertolotto, the sundial expert, principal of the Nautical School Camogli and probably the implementer of the largest sundial in the harbor which bears the date 1850. Riccardi, II. 106; De Backer-Sommervogel V.525, 4; Cinti 177; Carli-Favaro 128; Tomash II.M34.