Castor & Pollux first appeared in the Lloyd's Register (LR) volume for 1791.

[2] Lloyd's List reported in September 1792 that Castor & Polleux, Codner, master, had been returning from Manfredonia when she caught fire at sea.

[1] On 21 March 1799 Castor & Pollux, Anderson, master, was at Deal, waiting to sail for the South Seas.

In February 1800 Castor & Pollux called in at Rio de Janeiro in want of refreshments and repairs.

[4][5] In May 1801 Lloyd's List reported that a Spanish ship of 24 guns had captured "Britannia, late Mortlock, of London", and Castor & Pollux, Anderson, master, in the Galapagos Islands.