oldlock wroteIts for a ‘ Solomon Henry ’ patent lock, patented in 1799 but made over a long period.
The example you have is fairly typical. .
Sad to say, keys are much more common than latches. Complete latches surviving in working order are quite uncommon now. There are normally 2 wards, but the number of differs is small. I have seen 2 different sizes of key, so that is another variation.
This was a key-operated development of the medieval ‘hatchet latch’ (from its shape), also known as a long latch.
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