Doğum Tarihi - 1580, Leiden, Hollanda
Ölüm Tarihi - 30 Ekim 1626, Leiden, Hollanda
Willebrord Snell studied law at the University of Leiden but was very interested
in mathematics and taught mathematics even while he studied law. From about 1600
he travelled to various European countries, mostly discussing astronomy. In 1602
he went to Paris where his studies continued. He received his degree from Leiden
in 1607.
Snell's father, Rudolph Snell (1546-1613), was professor of mathematics at
Leiden and, in 1604, Willebrord visited Switzerland with his father. In 1613 he
succeeded his father as professor of mathematics at the University of Leiden.
In 1617 Snell published Eratosthenes Batavus, which contains his methods for
measuring the Earth. He proposed the method of triangulation and this work is
the foundation of geodesy.
Snell also improved the classical method of calculating approximate values of p
by polygons. Using his method 96 sided polygons give p correct to 7 places while
the classical method yields only 2 places. van Ceulen's 35 places could be found
with polygons of 230 sides rather than 262 .
Although he discovered the law of refraction, a basis of modern geometric optics,
in 1621, he did not publish it and only in 1703 did it become known when Huygens
published Snell's result in Dioptrica. Snell also discovered the sine law.
Snell studied the loxodrome, the path on the sphere that makes constant angle
with the meridians. This appears in Tiphys batavus published in 1624, a work in
which he studied navigation.