push the box as far right as you can – against the huge cog – and jump onto the platform above (**don't pull the lever yet**)
then jump up right onto the cog and climb around the circumference
step on the glowing blob on the right-hand side of the cog to get the achievement - Climbing the Cog
now climb up the ladder on the right, and walk back across the cog to the left to continue the chapter
FYI: the video shows him going all the way over, up and then down a ladder. instead, you can simply just follow the cog down to get the achv and then use the ladder to get back over the cog to the left and back to the lever. the vid is more for a frame of reference to locate the blob/achv.
**guide credit: Mike Rose of DIYGamer** edited by geegers78
**video credit: BrainLazyVideos
see also: DIYGamer complete walkthru and guidehttp://www.diygamer.com/2010/07/limbo-xbox-live-arcade-walkt...