Willebrord van Royen Snell was a prominent mathematician and astrologer. His name and works have been associated with the law of refraction for centuries in the west. However, it was later discovered that the law was discovered by Ibn Sahl, and that Snell only developed and furthered his research on the law. Legend has it, that Snell was a mathematical genius and developed a new method to calculate the mathematical function, ‘Pi’, which brought about a significant development in the field of mathematics. After such advanced improvements, he built further theories on the law of refraction, which he rediscovered in 1621. In addition to his mathematical genius, Snell published various works that defined new boundaries in mathematical and scientific research. Some of his most celebrated works are ‘Eratosthenes Batavus’ and ‘Tiphys Batavus’.
As his career peaked, Snell travelled extensively around Europe to study and discuss astronomy. Here, he collaborated and worked with some of the best in the field of astronomy, such as Johannes Kepler and Tycho Brahe. Scroll down to know more about this interesting personality.
Childhood & Early Life
Willebrord van Royen Snell was born in Leiden around the 1580’s. His father, Rudolph Snell van Royen, was a mathematics professor at the University of Leiden, which probably explains Snell’s interest in the subject. Willebrord Snell was the eldest of the three children born to his parents, but his two siblings died in their childhood. Although Snell’s date of birth has often been disputed, the common consensus is that he was born around 1580 or 1581. Snell’s father wanted him to study law at university; however, Snell took after his father and decided to opt for mathematics. He was homeschooled and studied under the guidance of Ludolph Van Ceulen. By 1600, Willebrord Snell was a full-fledged mathematics teacher and took over his father’s position at the university after his death in 1613.
By 1615, Snell was intrigued about the geometry and the dimensions of the earth and thus, decided to carry out a new method of finding out the radius of the planet. He concluded that he would do this by determining the distance of one point on the earth’s surface and the latitude of another point, by the means of ‘triangulation’. He published the results of this research in a famous book ‘Eratosthenes Batavus’ in 1617. At the university, Snell taught his students the works by Ramus, Stevin and Van Ceulen and also introduced the system of reducing the teaching load to further research on and dwell deeper into the works of the famous mathematicians.
After his father’s death, Snell made significant contributions in the field of mathematics that portrayed more complex mathematical skills than his father. He was instrumental in the restoration of the works by Apollonius on the subject of ‘plane loci’ and the works of Pappus. He reworked on and republished these two great works under the title ‘The Revived Geometry of Cutting off of a Ration and Cutting off of an Area’. He furthered his research into the works of Apollonius and published a reconstruction called ‘Apollonius Batavus’.
Snell’s Astronomical Interests
Throughout his career, Snell had been interest in the field of astronomy and published several works on the same. However, Snell was often ridiculed for not having made observations on his own and using the works of other famous astronomers. It is believed that one of Snell’s astronomical works, ‘Observationes Hassiacae (1618)’ was in fact, written from the observations recorded by Tycho Brahe and Joost Burgi. Knowing that he was being scorned at, Snell decided to publish a book containing his own observations and thus, came up with ‘Descriptio Cometae’ in 1619, that studied the movements of comets.
Legend has it, that Snell strongly criticized the works of Aristotle and Copernicus and mentioned that their works would turn out to be harmful for science if other astronomers and scientists followed them with so much reverence. However, he did believe in the theory of the earth’s centered system and agreed with the works of Ramus and his father.
Snell also improved the classical version of calculating approximate values of ‘pi’ by polygons which he published in 1621, called ‘Cyclometricus’. Using this method, 96 sided polygons branched to 7 theorems in pi, whereas the classical method only yielded 2 theorems. This theory appeared in Snell’s publication for the first time and was widely accept by his successors. Willebrord Snell is also credited for having discovered the law of refraction in 1621, which was only published in 1703 in ‘Dioptrica’. A manuscript with a treatise on the study of optics was also included in these works which helped him construct the path that led to the discovery of Snell’s Law.
Apart from the study on optics, pi and the law of refraction, Snell was also credited for having contributed generously in the subject of the ‘loxodrome’—the path on the sphere that made a constant angle with the meridians. The result of this study was published in another one of this famous works, ‘Tiphys Batavus’, published in 1624.
In 1626, at the age of 46, Snell passed away from a condition called ‘colic’, which caused paralysis of his arms and legs. The illness is believed to have lasted two weeks, following which he succumbed to it.
1580: Willebrord van Royen Snell was born in Leiden, Netherlands.
1600: Travelled to European countries to learn more about astronomy and taught Law and Mathematics at the University of Leiden.
1608: Received the degree for Master of Arts from Leiden.
1613: Took over his father’s position as mathematics professor at the university.
1619: Published his works on comets, ‘Descriptio Cometae’.
1621: Improved the method of calculating ‘pi’ and published the results in ‘Cyclometricus’. He also discovered the Snell’s Law this year.
1624: Studied the loxodrome and published the results of his research in ‘Tiphys Batavus’.
1626: Passed away on 30th of October after a brief, colic illness.