- Sep 3 James Harrison, Scottish-born inventor (b. 1816)
- Sep 7 Hamilton Fish, American politician (Governor of New York), dies at 85
- Sep 8 Luke Short, American Old West gunslinger and saloon owner, dies of dropsy at 39
- Sep 15 Thomas Hawksley, English civil engineer (b. 1807)
- Sep 19 Alexander Tilloch Galt, Canadian politician, a father of Canadian Confederation, dies at 76