Setting email message width in mutt

[Frisco Rose <rosef@nemo.physics.ncsu.edu>]

Greetings,

I have been following the thread  Re: A Pet Peeve about posting on the lists
and decided to try using mutt instead of pine to read my email. However I cannot
seem to find a way to set the default line length when composing a message.

I have tried the following;
man mutt
less /usr/doc/mutt/manual.txt
http://www.mutt.org
man vim

The last one is because it seems that mutt is using vim on the machine where I 
read my email. I am composing this message in mutt and if the lines are to long
it is because I have my terminal set very wide and I am guessing at the right
place to hit return and start a new line.

Any help would be greatly appreciated. TIA
-- 
Frisco Rose     REU Student
rosef@nemo.physics.ncsu.edu