Adriaan Anthonisz
Adriaan Anthonisz was a Dutch mathematician, surveyor, cartographer, and military engineer who specialized in the design of fortifications. As a mathematician Anthonisz discovered in 1585 the ratio of a circle's circumference to its diameter, which would later be called pi.Life
Anthonisz served as burgomaster of Alkmaar in the Netherlands from 1582.
Adriaan fathered two sons, and named them both Metius. They each became prominent members of society. Adriaan Metius was a Dutch geometer and astronomer. Jacob Metius worked as an instrument-maker and a specialist in grinding lenses and applied for patent rights for the telescope a few weeks after Middelburg spectacle-maker Hans Lippershey tried to patent the same device.Career
In 1585 Anthonisz discovered that the ratio of a circle's circumference to its diameter, later called pi, approximated the fractional value of. His son Adriaan Metius later published his father's results, and the value is traditionally referred to as Metius' number'.
He is regarded as one of the first military engineers to apply the principles of the Dutch fortification system.
Some of his professional accomplishments included mapping the Berger lake and expanding and fortifying Naarden and Muiden.
