🚀 go-pugleaf

I once said I didn't want to read Volume B of the Computers
and Typesetting series (TeX: The Program), and that I was waiting
for the movie to come out.  Well, I take it back.  I have long
wondered why the reference point for DVI files, instead of being
at the upper left corner of the page, is 1 inch down and 1 inch
in from the corner.  I finally resolved to go to the library and
check out the source and find out.

Naturally, I can't find a reason anywhere.  What's more, I was
surprised to see that "\hoffset" and "\voffset" are not in the
index!  The only relevant remark I've found so far is in
section 590, where it says

  the standard convention for output on normal size paper is
  to position each page so that the upper left-hand corner is
  exactly one inch from the left and the top

It does not say (in that section at least) *why* this is the
convention, or what in the DVI file (if anything) specifies this,
or what changes in the DVI file if you use \hoffset and
\voffset to reposition the print image on the paper.

The library's copy of Volume B is apparently a first edition--
at least, all it says on the copyright page is "copyright 1986"
with no indication of which printing it is or anything like that.
But surely \hoffset and \voffset were already part of TeX82 in
December of 1985 (which is the date on Knuth's preface)?

Any hints from DVI gurus or TeXperts familiar with The Program
would be most welcome.

--Cameron Smith
  cameron@symcom.math.uiuc.edu