The Onedin Line (1971) : 6x7

Letty tells James that she is pregnant and Charlotte gives William the same news. He is stunned and, as he does not love her, refuses to marry her - although she has confided in Samuel that she believes they will wed. Samuel takes the news badly and, when he and James, sailing to Ireland, come across a deserted steamer full of high explosives, feels sufficiently reckless to help James put the cargo overboard, though they are successful and claim the salvage rights. William turns twenty-one and inherits his mother's share of the Frazer yard, which he intends to sell.