Adding to that, the fact that the disengagement is mechanically (self) operated and does not depend on gravity odds like in the dog lock ... am i right ?

If i get your point ... can't you do that with two fingers (thumb & index) of the same hand ?

I've never actually held a Portuguese lock to study. So this information is most helpful. I was completely unaware of the "cam" action of pushing the safety catch forward while positioning the hammer in the firing position. The catch/brake would not have to move forward very much. This safety is a much more interesting feature than I originally imagined. And very clever.

Philip: Thanks for the photos of the three locks. I was drooling on my keyboard when I first viewed them. They look to be in wonderful condition. And really shows the variety/combinations of Portuguese lock making. And thanks for the informative descriptions. So interesting.

From a shooter's perspective: When I shoot my replica 17th Century English musket, with a Jacobian style transition lock, engaging the safety is very simple. After firing, I simply lower the musket to my waist. Then, while pulling the hammer back with my thumb at the same time pulling upwards on the dog catch with my two smaller fingers till it engages the notch in the hammer. You can do it without looking after you get use to it. Still, it's not as convenient as the second notch on the tumbler for the reason that Philip explains.
I can't visualize the safety on the Portuguese locks being any more difficult. Just pulling the hammer back and at the same time using the index finger to pull the catch backward. Just a different method accomplishing the same thing.

Rick

See how early this safety brake system was implemented, used in earliest known "pistols" to clavinas (petronels) from the second, third and last quarters XVI to first quarter XVII centuries, in the various types of lock.
(not per quoted order)

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