Andrew Gabriel wrote:
They were called "Scruits" (TM) ...
I have a number of old books on wiring (stangely, I find the
history of it interesting). The most recent one with any reference
to this type of connector is about 1935, and that's only in a
picture -- I suspect thet were probably rather obsolete even by
then.

I had an electrical wiring book in the mid 1980s which recommended them.
Can't remember which one though.

Owain