[COFF] Scribe (Typesetting System) and Unix

Hi all, Given the recent (awesome) discussions about the history of *roff and TeX, I thought I'd ask about where Brian Reid's Scribe system fits in with all this. His thesis is available online here: http://reports-archive.adm.cs.cmu.edu/anon/scan/CMU-CS-81-100.pdf, and in my opinion is very interesting (also cites papers on roff and TeX). Does anybody know if Scribe was ever used on Unix systems? Does it exist at all today? Thanks :) Josh