We're all wrong. Here's some more info on that compressor. Looks like it was powered by electricity. There's a video on youtube of what I think is one....although it doesn't specify. Looks like the same type armature and says 750HP and 2300V. But here's an article about them. Clearly this one is electric. What appears like a steam engine is the compressor pump. lol
[URL]https://lakesidetek.com/IngersollPics.htm[/URL]