Francesco Barozzi (in Latin, Franciscus Barocius) (9 August 1537 – 23 November 1604) was an Italian mathematician, astronomer and humanist. Life Barozzi was born on the island of Crete, at Candia (now Heraklion), at the time a Venetian possession. He was the son of Iacopo Barozzi, a Venetian nobleman, and Fiordiligi Dorro. Barozzi was educated at Padua, and studied mathematics at the University of Padua. The estate on Crete, inherited from his father, yielded him an income of 4,000 ducats, though he seems to have lived in Venice for most of his life. He was thus able to function as an independent scholar, and does not appear to have held any academic posts, although he did lecture on the De sphaera of Sacrobosco at the University of Padua in 1559. Barozzi translated many works of the ancients, including Proclus’s edition of Euclid's Elements (published in Venice in 1560), as well as mathematical works by Hero, Pappus of Alexandria, and Archimedes. Mathematics Barozzi helped in the general reappraisal of the geometry of Euclid, and corresponded with numerous mathematicians, including the German Jesuit Christopher Clavius. His original works include Cosmographia in quatuor libros distributa summo ordine, miraque facilitate, ac brevitate ad magnam Ptolemaei mathematicam constructionem, ad universamque astrologiam institutens (1585), which he dedicated to the Duke of Urbino. This work concerns the cosmography and mathematical systems of Ptolemy. Barozzi also discussed 13 ways of drawing a parallel line in his Admirandum illud geometricum problema tredecim modis demonstratum quod docet duas lineas in eodem plano designare, quae nunquam invicem coincidant, etiam si in infinitum protrahantur: et quanto longius producuntur, tanto sibiinuicem propiores euadant (1586). In his Opusculum: in quo una Oratio et due Questiones, altera de Certitude et altera de Medietate Mathematicarum continentur, Barozzi stressed that "the certitude of mathematics is contained in the syntactic rigor of demonstrations." Barozzi dedicated this work to Daniele Barbaro. Other works He also wrote Rythmomachia (1572), which he dedicated to Camille Paleotti, a Senator of Bologna, a work that is based on the mathematical game of the same name, also known as "The Philosophers' Game." As an antiquarian, he copied many Greek inscriptions on Crete. His collection of inscriptions was later inherited by his nephew Iacopo Barozzi (1562–1617), who edited and expanded it. This collection was later acquired in 1629 by the University of Oxford. They are wide-ranging in date and subject matter and can still be