[3] 2nd whaling voyage (1801–1804): Captain Henry Mackie acquired a letter of marque on 19 September 1801.

[4] Thetis, Mackie or Mackay, master, was several times reported at the Galápagos Islands.

[3] On her return Timothy Cheesman sold Thetis to Pearson, and she became a coaster, after having undergone a good repair.

In 1811, Thetis, Pearson, master, made a voyage to Quebec and arrived back at Gravesend on 30 November.

On 25 February 1812 the snow Thetis, Pearson, master, of South Shields, was lost on the Platter Sand, near Harwich.