Here's the Adana version of the common screw stick. These sticks are very common in England, where they were made by the Adana Company, the primary manufacturer of small presses for hobby printers in England. The stick is a very simple mechanism, with a knee whose only unique feature is that it has the letter "A" incorporated into it, standing for Adana - the end of the stick is curved to conform to the shape of the knee. The clamp extends around the rail and under the bottom of the stick, with a screw of brass.
This particular stick is cast from what I believe is referred to as "pot metal" - I'm not sure if I'm correct on that. But it is very heavy and greyish in color. I have other Adana sticks that are made from steel or aluminum.