Blacksmith Joseph Peavey's name went down in history as the inventor of the improved cant dog. Used to roll logs, break jams, pry rocks, tighten chains, and push over trees (with a pole, known as a "killig" or "kilhig"), the peavey is the logger's all purpose tool.
The cant hook is similar, but is used in sawmills. It looks like a peavey except it has a metal ring with a lip on its end instead of a point. In pre-pushbutton sawmill days, cant hooks were used to roll the cant after a slab was cut off. (A log that has had one or more slabs cut off it is called a "cant".)