According to the inscription on the ½ c stamp the vessel shown is the first United States war vessel, the Hanna. I think (E Argyle) this must be a mistake in the name for the first armed vessel to sail under Continental pay and control was the Hannah, originally owned by John Clover, of Marblehead Mass. This vessel was taken over by the Continental Forces on August 24, 1775, She was the beginning of the small fleet fitted out by George Washington in the autumn of 1775 to aid him in the siege of Boston by capturing provisions ships making for the harbour from British ports.
Her first captain was a Confederate Army captain, Nicholson Broughton, and her crew was recruited from John Clover's regiment. After fitting out, the Hannah sailed on September 5. Next day she captured the sloop Unity with naval stores and provisions, returning to Beverly Mass. Her career ended on October 10 1775, when, whilst cruising off Boston, she was run ashore by the Royal Navy sloop Nautilus. The townspeople saved the Hannah from destruction or capture, but she was soon after decommissioned. SG406