Snell’s
This type of Hand Point Lever was known to be in use by 1910 and was
perhaps the preferred type for new installations by 1915. The operating
mechanism was simple and non-locking.
At least one of these was in use as late as 1990!
Ref:
South Western Circular Volume 12, No.7, July 2002. Can be obtained from
British Library (and any other library) under ref ISSN 0309 - 5053.
4mm
& 7mm Point lever Snell's pictured below |