Actually there were more types than that, including a 13A round pinned plug, with one of the pins (the live obviously) been a screw-in fuseThere are still houses in the Uk with those bulgin 5 and 15a sockets, allthough I've never seen a dual socket like those.
The ones before that were wylex, 2 square and one round pin for earth.
The 13A screw in fuse type were quite rare, the much more common 5A and 15A were un-fused.Actually Nige I thought the round pin plugs the o/p posted were the screw in fuse type, I guess there were several.