Chainsaws had been around for years but didn't work all that well until 1948 a guy in Oregon invented the chipper chain that made about three orders of magnitude difference.
Wiki says the patent for this Sally Saw  from Cummings Machine in Boston, was filed in 1945 but the plate on this saw says patented 1949.
4 horsepower, 4 cycle motor, 70 lbs, and the blade doesn't spin all that fast plus really isn't aggressive.
It's a man eater, looks cool hanging in the garage, shed, or barn, but use a chainsaw to cut.