Scientists from Amsterdam

Jean Abraham Chrétien Oudemans (Amsterdam, 16 December 1827 – Utrecht, 14 December 1906) was a Dutch astronomer. He was the director of the Utrecht Observatory from 1875 until 1898, when he retired.
Oudemans was born in Amsterdam, son of the poet, teacher and philologist Anthonie Oudemans Sr. and Jacoba Adriana Hammecker. He entered Leiden University when he was just 16 as a student of the noted astronomer Frederik Kaiser. He became a high school teacher in Leiden when he was just 19 (1846). The next six years he worked on his dissertation on the determination of the latitude of Leiden. Next he studied asteroids and variable stars, meanwhile hoping for an academic appointment. In 1855 he became member of the Royal Netherlands Academy of Arts and Sciences.
He married Pauline Adriana Verdam (the daughter of a well-known mathematics professor Gideon Jan Verdam ) in 1856. In the same year he was appointed a professor at Utrecht University and became the first director of its observatory. However, his interest drew him towards geography. He traveled to the Dutch East Indies as head surveyor, and worked in that capacity for 18 years, publishing his works on the triangulation of the island of Java in six books.In 1874 he organized an astronomical expedition to the island of Réunion to observe the transit of Venus but, due to bad weather, the results were disappointing.Oudemans crater on Mars was named in his honor.
A brother was the botanist Corneille Antoine Jean Abram Oudemans. One of his sons was Anthonie Cornelis Oudemans Jzn, one of the fathers of cryptozoology.

Friedrich August Ferdinand Christian Went (June 18, 1863 – July 24, 1935) was a Dutch botanist.
Went was born in Amsterdam. He was professor of botany and director of the Botanical Garden at the University of Utrecht. His eldest son was the Dutch botanist Frits Warmolt Went, who in 1927 as a graduate student worked on plant hormones, specifically the role of auxin in phototropism.
He became member of the Royal Netherlands Academy of Arts and Sciences in 1898.Went died, aged 72, in Wassenaar.

Frederik Schuh (7 February 1875, Amsterdam – 6 January 1966, The Hague) was a Dutch mathematician.

Ernst Julius Cohen ForMemRS (7 March 1869 – 6 March 1944) was a Dutch Jewish chemist known for his work on the allotropy of metals. Cohen studied chemistry under Svante Arrhenius in Stockholm, Henri Moissan at Paris, and Jacobus van't Hoff at Amsterdam. In 1893 he became Van't Hoff's assistant and in 1902 he became professor of Physical Chemistry at the University of Utrecht, a position which he held until his retirement in 1939. Throughout his life, Cohen studied the allotropy of tin.
Cohen's areas of research included polymorphism of both elements and compounds, photographic chemistry, electrochemistry, pizeochemistry, and the history of science. He published more than 400 papers and numerous books.In 1913 he became member of the Royal Netherlands Academy of Arts and Sciences. He was elected a Foreign Member of the Royal Society in 1926. Following the 29 April 1942 decree that Dutch Jews wear the yellow badge, he was arrested by Nazi police for non-compliance and forced to resign.According to Margit Szöllösi-Janze, in her book, Science in the Third Reich, Cohen "put great efforts into restoring the relationships of Western European scientists with their German colleagues after the First World War."
He was killed on 6 March 1944 in a gas chamber at Auschwitz concentration camp.