I was just poking around the computerhistory.org website, searching for Knuth stuff.
The second or third hit when I search for "Knuth" is this one: https://computerhistory.org/blog/the-apl-programming-language-source-code/ . It's not just about APL, it actually has a downloadable copy of the source code. And it points to an executable version, apparently a packaged up Hercules running that code. Nice. I'll have to give it a try. paul
