What a treat. The pictures brought back great memories. November 1st 1973 I went to work as a blacksmith helper at Kaiser Steel, Fontana Steel Mill. The very first thing I was trained on was how to operate a hammer. There were two hammers in the blacksmith shop. A single leg Chambersburg High Frame Hammer, I do not remember the weight - it was at least twice the size as the small hammer I suppose it was in the neighborhood of 1000#, and a 200# Chambersburg. I spent about 3 years in the blacksmith shop. Made all kinds of tools, many of which I still have - lots of hand hammers. I became what I would consider an expert "driver" of the High Frame, but only satisfactory on the 200# hammer. I did not run the small hammer much. The head blacksmith's helper was the one that ran the small hammer most of the time. He was an "old" man then and had been running that hammer for 20 plus years.
The hammers in the blacksmith shop were air powered.
BTW. In the steel mill the hammer driver sat in a chair. The chair was tall like a stool. This allowed better control of the choke and throttle. I was suprised to see the hammer driver standing to opperate the 200#er because the choke and throttle controls were very touchy comparied to the High Frame. The small hammer took alot more concentration to operate.