Besides saws, axes, and wedges, he also needed peaveys,
cant hooks, pike poles, and log dogs.
The origin of the cant hook seems to be lost in the fog of history, but more is known about the peavey, which was named after its inventor, Joseph Peavey.
So, to answer the original question, the main difference between a cant hook and a peavey is the iron or steel spike at the business end of the peavey.
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Cant hooks are invaluable if you're going to do much work with logs.
Cant hook: A stout wooden lever used for handling logs, usually with a blunt metal-clad end and a movable metal arm with a sharp spike.
Then we'd roll the log with our
cant hooks and repeat the process to slab off the other three sides.
When you're done reading Calked Boots and
Cant Hooks it's not hard to believe at all.