Dinty,
It's a floorboard saw.
It has a ratchet drive which is identical to a Stanley brace.
Foot goes into the aluminium section so you can push down then across as you cut a floorboard.
Used years ago in the UK to cut floorboards when installing central heating etc., I guess it dates to the 50's/60's.
Can't find it on an internet search and I've only seen two.
Markings are
Floorboard Cutter
Model TC4
Patents Pending
Made in England by
Melway Products
Maidenhead
Berkshire
Colin

