53:16 · This ideogram is known as the Plimsoll mark (after its inventor, the British coal merchant and MP Plimsoll, living in the latter half of the nineteenth century, who took a great interest in the safety of cargo ships). The ideogram was introduced in 1870 and painted on the sides of ships by the water line. The letters stood for different parts of the oceans with their different concentrations of salt, i.e. different abilities to bear ships' weights.
    This is a Plimsoll mark on a Swedish ship, so the letter markings are others on for instance American ships. VNA, however, in Sweden denotes winter freeboard in the North Atlantic, and SSV means summer freeboard in sweet water. Each line indicates the allowed freeboard in the part of the oceans where the ship is transporting cargo.