Box locking mechanism from the side

Showing the tenon on the boxwood and the mortice in the brass, together with the enclosed spring that returns the hook to lock position, attached by a screw; the brass had to be drilled and tapped for it.Turning the knob to the front moves the hook out of a wooden slot machined into a small piece of oak glued to the inside of the lid; on closure the slope on the hook meets a matching slope in this piece to ensure that the lid is held tightly shut