Top lever release crossbows?
I am looking for information on crossbows made before 1600 that used a top lever release. This is a lever mounted to the top of the stock which when the long rear end is depressed, it turns on an axle and the short front end lifts the string out of a notch. The only reference that I have seen on these is a mention of the finding of the partial remains of a child's toy crossbow that used such a mechanism.
Does anyone have any information on such a release?
Thank you for any help you can give.
Newark, California, USA