Gear set-up request

I want to know what my Super 7 gears are set up for. I can`t find anything in the various books that makes sense! I`ve drawn a nice pisture but I don`t seem to be able to attach anything to this post. I could email it to anyone who might be able to help. My email address is
glenn_burnage@tiscali.co.uk
Cheers, Glenn

Gearing of lathes for screw cutting by Brian Wood