from
Bouvier's Law Dictionary, Revised 6th Ed (1856)
MISSING SHIP, mar. law. When a ship or other vessel has been at sea for a
much longer time than she ought to have been, she is presumed to have
perished there with all on board, and such a vessel is called a missing
ship.
2. There is no precise time fixed as to when the presumption is to
arise, and this must depend upon the circumstances of each case. 2 Str. R.
1199; Park. Ins. 63; Marsh. Ins. 488; 2 Johns. R. 150; 1 Caines' R. 525;
Holt's N. P. Rep. 242.