A Power Take-Off Drag Saw

This piece of  history is rusting away and sinking into the soil.  It was powered by a tractor pto and was used to buck trees into logs prior to the advent of chainsaws.  The logger or farmer would pull the saw into the woods and set the saw perpendicular to the felled tree.  He’d engage the saw and it would cut the log.  It looks like it would be slow compared to a chainsaw, but it must have been a labor saver at the time.