From 1797 she made two voyages from Liverpool as a slave ship in the triangular trade in enslaved people.

[a] 1st voyage transporting enslaved people (1797–1798): Captain Thomas Smith acquired a letter of marque on 15 April 1797.

This led the government in the Danish West Indies to encourage the importation of captives prior to the ban taking effect.

Records for the period 1796 to 1799 show that 24 British enslaving ships, most of them from Liverpool, arrived at St Croix and imported 6,781 captives.

[b] Then on 21 March a squadron under the command of Captain Sir John Borlase Warren, in the 74-gun third rate Canada, and including Phaeton and Mermaid, recaptured Tonyn.

[4] 2nd voyage transporting enslaved people (1798–1799): Captain James Towers sailed from Liverpool on 21 November 1798, bound for the Congo River.

[10] In January 1800 Lloyd's List reported that Tonyn, Towers, master, had been sunk in Waterford harbour after having been run into.