Giovanni Padovani (or Paduani) (b. c. 1512) was an Italian

mathematician A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, structure, space, models, and change. History On ...

and

astronomer An astronomer is a scientist in the field of astronomy who focuses their studies on a specific question or field outside the scope of Earth. They observe astronomical objects such as stars, planets, natural satellite, moons, comets and galaxy, g ...

. He lived in

Verona Verona ( , ; vec, Verona or ) is a city on the Adige River in Veneto, Northern Italy, Italy, with 258,031 inhabitants. It is one of the seven provincial capitals of the region. It is the largest city Comune, municipality in the region and the ...

and was a student of

Pietro Pitati ''For the painter Bonifazio de' Pitati, see Bonifazio Veronese.'' Pietro Pitati (in Latin, Petrus Pitatus) (?-fl. ca. 1550) was an Italian astronomer and mathematician. Bernardino Baldi, in his ''Cronica de matematici'' (1707) calls Pitati a no ...

. He published a number of esteemed treatises on various astronomical and mathematical subjects, the most well-known of which was a treatise on the

sundial A sundial is a horological device that tells the time of day (referred to as civil time in modern usage) when direct sunlight shines by the apparent position of the Sun in the sky. In the narrowest sense of the word, it consists of a flat ...

called ''Opus de compositione et usu multiformium horologiorum solarium, pro diversis mundi regionibus, idq(ue) ubique locorum tam in superficie plana horizontali quam murali quoruscumqu(ue) exposita sit, pertractans'' (

Venice Venice ( ; it, Venezia ; vec, Venesia or ) is a city in northeastern Italy and the capital of the Veneto Regions of Italy, region. It is built on a group of 118 small islands that are separated by canals and linked by over 400 ...

, 1570). An expanded and re-written version came out in 1582. This manual includes instructions for the manufacture and laying out of mural (vertical) and horizontal sundials; contains extensive tables of declinations for various

latitude In geography, latitude is a coordinate that specifies the north– south position of a point on the surface of the Earth or another celestial body. Latitude is given as an angle that ranges from –90° at the south pole to 90° at the north pol ...

s with both occidental and oriental examples; and provides instructions for the calculation of latitudes. This last section includes a description of a sundial calibrated for the measurement of unequal hours, such as those used in the ecclesiastic

calendar A calendar is a system of organizing days. This is done by giving names to periods of time, typically days, weeks, months and years. A date is the designation of a single and specific day within such a system. A calendar is also a physi ...

, which foresaw twelve hours of light and twelve of dark, which was subject to severe seasonal variations.

Sources

Papyrus Rare Books

{{DEFAULTSORT:Padovani, Giovanni 16th-century Italian astronomers 16th-century Italian mathematicians 1512 births Year of death missing