The saw in the second picture was quite a sight.
The saws are one of my favourite things to watch.
First off, the gril driving the engine running the saw couldnt have been much over 12 year old. Second, thats one mean blade, and its going mighty fast. The guys were stepping through the drive belt while it was moving, and reaching across the blade.
They used wedges to move the logs (2-3' dia) into the right place.
When the blade found a knot in the wood the belt would be stretched tight on the input side transmitting the power, and the slack side would drag along the ground, absolutely no slip atall.
BTW, everything is done with steam, lifting the logs, powering the equip, everything.