{"product_id":"fabri-ottavio","title":"FABRI, Ottavio","description":"\u003cp\u003eAn excellent copy of the first edition of this important work on the application of triangulation. Ottavio Fabri (fl. late C16-early C17) was an Italian mathematician of whom little is known. His greatest contribution to the discipline, immortalized in this work, was the invention of the  squadra mobile , a brass geometrical instrument to  measure, level and transfer onto paper every distance, height and depth , with applications in astronomy, geometry and the measuring of terrain. The edition was printed in two issues with differing preliminaries, though no priority has been established. The first section is devoted to measurements and includes comparisons between units used in different cities (the  Braccio toscano  in Florence, the  Tornadure  in Cervia) or countries ( Piedi  in France and the Trevigian  Pertica  in Cologne). He proceeds to explain the construction of the instrument; this part was illustrated by an engraved plate portraying the  squadra mobile , absent in most copies. The best material for the instrument, he found, is copper, a piece of which  as thick as a knife s back  can be bought  from any ironmonger in town . He even advertised the best craftsman in Venice to assemble the instrument,  M. Battista degli Horologli  in his Spadaria shop, who made clocks and scales. The rest, illustrated with handsome engravings, explains the most common applications of the instruments in measuring from various positions the distance, depth and height, in relative and absolute terms, of buildings, hills, allotments, etc. The  squadra mobile  could even be used to map a city s area without a compass both from inside or outside its walls. Illustration XIII pasted on p. 37 appears to have been an editorial afterthought as it is also found in the NYPL copy.\u003c\/p\u003e","brand":"FABRI, Ottavio","offers":[{"title":"Default Title","offer_id":57816160207183,"sku":"L3013","price":2750.0,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1016\/2425\/0703\/files\/Fabri-L3013-1.jpg?v=1781794900","url":"https:\/\/sokol-books-ltd.myshopify.com\/products\/fabri-ottavio","provider":"Sokol Books Ltd","version":"1.0","type":"link"}