In 1970 the Irish Post issued a single stamp of 4 p for the 250th Anniversary of the Royal Cork Yacht Club.
The stamp is designed after a painting made by the painter Peter Monamy in 1738 to the order of William the 4th Earl of Inchiquin.
The painting shows most probably a cutter rigged yacht with a starboard view and a bow view of the same yacht.
The painting is now in the possession of the Royal Cork Yacht Club.
Ireland 1970 4p sg279, scott?
More info you can find on the painting on: http://www.cichw.net/pmyachtco.html