http://www.legislation.gov.uk/id/ukpga/Vict/36-37/88

http://www.legislation.gov.uk/ukpga/Vict/36-37/88/section/4

Slave Trade Act 1873

An Act for consolidating with Amendments the Acts for carrying into effect Treaties for the more effectual Suppression of the Slave Trade, and for other purposes connected with the Slave Trade.