It's The Great Tantalizer Puzzle, dating from about 1918. I was sent it by Matthew Barr, who is receiving his PhD this week at Glasgow University. I was his external examiner, and he wanted me to have this as a gesture of appreciation. I'm not entirely sure why, as he did all the work on his PhD himself; all I had to do was to agree with what was pretty obvious anyway (that is, his work was indeed worth a PhD).
Still, I'm not churlish enough to reject a present (and I'm pretty sure it doesn't meet the university's definition of an attempted bribe), so I'm actually pretty chuffed with it. I hadn't thought that antique puzzles might be a thing, and now I know they are I'll look out for more.
As for the puzzle itself, I think I solved it over lunch but I'm not entirely sure as I don't know what its rules are regarding the ends of the blocks. If S. Guiterman & Co. Ltd. still have their offices at 35/36 Aldermanbury, London E.C., perhaps I'll contact them and ask for the official solution.