They served in the Mediterranean and South Atlantic, and latterly on fishery protection duties off Scotland.

They were designed by the builder, Robert Napier and Sons and approved on 17 April 1844 by the Surveyor of the Navy, Sir William Symonds.

They were each fitted with a Napier two-cylinder side-lever steam engine driving side paddles.

[1] Jackall served in the Mediterranean and at Ascension, and by 1864 she was employed on fishery protection duties off the west coast of Scotland.

[3] Lizard also served in the Mediterranean, and took part in an Anglo-French action in Uruguay in 1845, receiving serious damage and losing 4 men.