That sheet music: published 1941, with a picture of a rather well-dressed Sally in her 20s looking at a construction site in the distance ... presumably the Alley has been bombed in the Blitz and now it's being rebuilt. The words aren't very special, and I won't bother copying them (unless anyone really wants them). I guess the song is a follow-up to the pop version Q mentions, with the particular wartime associations. Probably intended as a morale-booster, too.

Steve