1220-1296

Italian Mathematician

Campanus of Novara, also known as Johannes Campanus and Giovanni Compano, produced a translation of Euclid's (c. 325-c. 250 B.C.) Elements that was destined to remain the definitive version among European scholars for two centuries. He also wrote on astronomy, providing the first European description of a planetarium.

As his title suggests, Campanus came from the town of Novara in Italy, where he was born in 1220. He served as chaplain to three popes beginning with Urban IV (r. 1261-64), and was working in the service of Boniface VIII (r. 1294-1303) when he died.

In 1260, Campanus produced his translation of Euclid. Original Greek texts of the latter's definitive work had long since been lost, but it had been preserved by Arabic scholars. Adelard of Bath (1075-1160) had been the first to translate the Greek mathematician back into a European language—Latin, used by scholars in the West at the time—but Campanus's version superseded even the translations produced by Adelard. When the first printed editions of the Elementa geometriae appeared in 1482, they used the translation of Campanus, which would remain dominant for the next two centuries.

In the realm of astronomy, Campanus wrote Theorica planetarum, in which he provided detailed observations on the construction of a planetarium. In addition, the book discussed the longitude of the planets and a geometrical description of the planetary model used.

In its data on planets, the Theorica showed the influence of the ancient Greek astronomer Ptolemy (c. 100-170), whose work had a powerful and sometimes unfortunate impact on late medieval science. Also evident was the influence of the Toledan Tables, edited in 1080 by the Arab astronomer al-Zarqali (Arzachel; 1028-1087) from computations made by al-Khwarizmi (c. 780-c. 850), al-Battani (c. 858-929), and al-Zarqali himself. Campanus's original contribution included determinations of the time for each body's retrograde motion, instructions for using the astronomical tables, and calculations of planets' size and distance from the Earth.

Campanus's Computus major concerned the properties of time and calendrical computations. His other works included Tractatus de sphaera, De computo ecclesiastico, and Calendarium.