William J Greenstreet's father was Thomas Greenstreet (born in Grantham, Lincolnshire about 1835) who was a Sergeant in the Royal Artillery. His mother was Catherine S Greenstreet, (born in Letterkenny Donegal about 1831). William had two younger siblings, Rosalie (born about 1864) and Cecil (born about 1866).
William J Greenstreet was educated at St Saviour's Grammar School, Southwark and entered St John's College, Cambridge in 1879, graduating in 1883. He was appointed assistant master at Doncaster Grammar School in 1882 and taught at Albert Memorial College, Framlingham, Suffolk from 1883 to 1885 and at Hull and East Riding College, Yorkshire from 1885 to 1888. He became Head Master of Cardiff Proprietary School from 1889 to 1891 and of Marling School, Stroud, Gloucestershire from 1891 to 1910. He was editor of the Mathematical Gazette for over 30 years as well as a translater of several French mathematical works.
William John Greenstreet married Ethel de Medina Spender from Bath in 1889. They had a daughter Dorothy (born about 1891). Ethel de Medina Greenstreet drowned in 1903.
Full details of William J Greenstreet's life and contributions to mathematics are given in an obituary which appeared in The Mathematical Gazette in 1930.
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Article by: J J O'Connor and E F Robertson