http://en.support.wordpress.com/settings/writing-settings/

I can adjust the size of the post box in Settings > Writing. Apparently this should be the first option on the page, but it's not there at all in my own menus. My post box is so tiny it's really impractical and hard to edit/write posts properly. Was this option removed since this article was written? Please tell me there's a way to do this...

Thanks.