Where to find the tex web output documenting the original tex implementation in pascal

If you have tex.web, you can do

weave tex.web

and then

tex tex.tex

(or pdftex). This is the first page:

The PDF is anyway already available on TeX Live by texdoc tex.

The (commented) source code is sold as a book: Volume B: TeX: The program. A documented listing of the source code of the TeX interpreter of Computers and Typesetting.