I did a quick search in my dictionary of old tools (yes, there is one!) but could not find your hook illustrated. I will have a word with my friend, who is a real expert. One thing I can confirm is that it is not a pole axe, which is quite different with a double head, one side has a triangular axe head, and the other has a long tube about 4" long and an inch diameter, sharpened at the end. This is the end used to kill a bull or cow, there is also a small hole at the handle end of the tube, which enables the blood to shoot out when it is used to strike the beast's head. Outlawed many years ago, although the slaughtering process was apparently both effective and quick.