scrollback buffer size in <shift><pageup>

Hi, Awhile back when I was going thru the install docs for some program, it mentioned a way to increase the size of the retained screen buffer for xterms. I think it was the -sl (for saved lines) option, but now I'm not sure if there was something else. So how do you increase this buffer size in xterms and console terms. Maybe some setting in .bashrc? -- use Perl; #powerful programmable prestidigitation