Setting default column width in SQLPLUS session

I currently set the following parameters when I run sqlplus:

set linesize 164;
set pause on;
set pause more;
set pagesize 50;
set numwidth 9;

I would also like to set a default column width, for display purposes, so that I get the first x characters in fields that are really huge. How would I do this? Received on Fri Feb 07 2003 - 11:12:11 CST