HMS Mars was a two-deck 80-gun second rate ship of the line of the Royal Navy, launched on 1 July 1848 at Chatham Dockyard.

[1] She served as a supply carrier in the Crimean War, and was fitted with screw propulsion in 1855.

[2] In 1869 she was moored in the River Tay,[3] off Woodhaven.

Here she served as a training ship for boys aged ten to sixteen from across Scotland, with up to 400 on board at any one time; these boys were usually homeless, orphans, or delinquents.

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