The ingenious Corkscrew Gulch turntable?

I am fascinated by the ingenious Corkscrew Gulch turntable on the Silverton Northern. The turntable replaced a wye, I believe.

North bound operations were simple. The grade through the turntable was downhill south to north. To take a string of mostly empty cars north to Ironton and Albany, first the engine moved east onto the turntable. The turntable was then spun so the engine was headed west and the engine exited the turntable. Gravity then pulled the cars onto the turntable which was then spun so the cars aligned behind the engine. The train then proceeded on its way downhill to Ironton.

The return is what has me confused. Now the train is mostly full cars and going uphill. The train must be worked through the turntable. There does not appear to be a passing track (s?) for the engine to maneuver the cars uphill through the turntable. Gravity maneuvered the cars downhill but the engine was needed to maneuver the cars uphill.

How was train maneuvered through the turntable uphill?