You can also adjust word wrap size etc by clicking on "Plain
    Text Settings" button

Please set the word wrap size to something huge like 255, so that the end of
lines you TYPE
are the only ones likely to appear in your message.  Otherwise, when you type
returns at
the end of the lines in your "who knows what sized" window (and perhaps in a
propotionally
spaced font as well), you'll likely end up with each line cut into a long line
and a short
line (once at the wrap column, and once again at YOUR end-of-line.)  This is
very annoying
to read.  (You can ignore this comment if you use an editor or typing style
that doesn't
involve any user-provided end-of-lines, of course.)

Thanks
Bill W

(Yes, the awful formatting above is intentional, to make my point!)