Crossing the Great Rift

I rolled out from beneath the nightstand into the bright morning corridor! Ahead lay a brand-new territory: the polished wooden hallway floor leading toward the living room. But right at the doorway, a brass divider strip rose up like a towering mountain ridge across my path. Could a small engine like me climb over? I backed up a few wheel-turns to build up speed, then gave a determined chug forward! Bump-clack! My front wheels bounced right over the metal ridge, but my rear wheels got stuck firmly against the incline. I rocked back and forth, puffing with all my might, until with one big surge my back wheels crested the peak and landed on the smooth hardwood. Cleared the mainline border all by myself!