Back in the late sixties, I worked for a soft-drinks firm, selling bottles from door to door an a regular round (a bit like a milkman, but weekly, rather than daily!) By coincidence, part of my "round" was in Wellyboro - where CapK is currently an esteemed resident.
In all of that part of the country, I was known as a "pop-man" and it was "pop" that I sold: but about five miles to the east of Wellyboro (I'boro and "Ah'm Ferr's", CapK) the concoction was known as "spruce" - I, therefore, was the "spruce-man" in those places.
Ironic, really, as I used to dress in scruffy jeans and a mock leather jacket and tacketty boots: anything less spruce you could hardly imagine.

I wonder if the kids of Irthlingborough and Higham Ferrers still call it "spruce"? I rather doubt it [sigh-e]