> "Four Yorkshiremen"
Zero computers? Ok, you win.
This is a later version of our computer https://youtu.be/NtAF-WfWyGU
To load the OS, you first had to hand key in a bootstrap loader in octal (base 8) on the front panel. The loader would then read the OS from paper tape into magnetic core.
Our computer was a PDP-8/i. Someone mentioned that the PDP-8/i was about as powerful as a Raspberry Pi. So, imagine a half dozen schools timesharing a Raspberry Pi.
Currently, I'm writing for the Apple Watch, which is more powerful than a Cray-2 -- a supercomputer that cost $16 Million in 1984.