[texhax] Large fonts and superscripts.

[Ludwig Mises]

I seem to be running into a dead end while trying to typeset a word in
a large font (say cmr20).  The superscript seems to remain in a much
smaller font than I would expect:

\font\bigfont=cmr20

{\bigfont Six$^{th}$}

Doesn't produce what I would think is a proportionally small
superscript.  Also, the superscript seems to show up in the middle of
the x vertically and is not offset above it. Am I missing something
obvious?

Thanks in advance,

Ludwig