Editing John Colenso (section)

==Early life and education==
Colenso was born at [[St Austell]], Cornwall, on 24 January 1814 the son of John William Colenso and Mary Ann Blackmore. His surname is Cornish and possibly originates from Colenso in the parish of [[St Hilary, Cornwall|St Hilary]], near [[Penzance]] in West Cornwall. It is a place name from the  [[Cornish language]] ''Kelyn dhu'', meaning "dark hollies".{{dub|date=July 2021}} His father (John William Colenso) invested his capital into a mineral works in [[Pentewan]], Cornwall, but the speculation proved to be ruinous when the investment was lost following a sea flood. His cousin [[William Colenso]] was a missionary in New Zealand.

Family financial problems meant that Colenso had to take a job as an [[Usher (occupation)|usher]] in a private school before he could attend university. These earnings and a loan of £30 raised by his relatives paid for his first year at [[St John's College, Cambridge]] where he was a [[sizar]].<ref name="acad" />  Showing talent in mathematics, in 1836 he was [[Second Wrangler]] and [[Smith's Prize]]man at the [[University of Cambridge]], and in 1837 he became fellow of St John's.<ref name="acad" /> Two years later he went to [[Harrow School]] as mathematical tutor, but the step proved an unfortunate one. The school was at its lowest ebb, and Colenso not only had few pupils, but lost most of his property in a fire. He returned to Cambridge burdened by an enormous debt of £5,000. However, within a relatively short period he paid off this debt by diligent tutoring and the sale to [[Longmans]] of his copyright interest in the highly successful and widely read manuals he had written on algebra (in 1841) and arithmetic (in 1843).{{sfn|Chisholm|1911}}