Stone cutting machine. Can also cut toes. Labeled "stone quarry cutting Malta". 98-second video:
https://www.youtube.com/watch?v=hUeB22Z2XW4
Previously:
https://www.homemadetools.net/forum/...2114#post75761
https://www.homemadetools.net/forum/...2093#post95470
https://www.homemadetools.net/forum/...3602#post99570