US postal service 1912, steamer AMERICA, picture postcard with sea mail duplex 21.6.12 and number "15" with 1 C to Elgin IL, USA, insufficiently stamped and postage due with Tax single circle postmark "U. S. Sea post / T 15" and transit New York ". Due 2 cents", postage due stamp 2 C on face pasted up, superb