This is the theme music from the Ealing comedy The Song of the Maggie (1954), composed by John Addison (1920-1998). The film tells the story of Alex Mackenzie, the veteran skipper of a near-derelict ‘puffer’ (a small steam-powered freighter) on the River Clyde in Scotland, and its crew of two, the Mate and Dougie, the wee boy.

Mackenzie needs money to repair the Maggie, so he tricks a hapless English shipping agent into loading a consignment of furniture onto his rickety tub instead of a much grander freighter. The owner of the wayward cargo, a bullying American businessman named Calvin B. Marshall, races after his belongings — he is fitting up a house in the romantic Scottish isles as a peace-offering for his estranged wife, who is on her way to join him — but Mackenzie always manages to stay one step ahead, and the pursuit teaches Mr Marshall some important life lessons.

It is played here by BBC Concert Orchestra, conducted by Rumon Gamba, in a recording supplied to YouTube by Universal Music Group.