Compagne desgravillons et du sable de la Brettone (Breton Sand and Gravel )
Another view of the layout. The lamp on the building has a grain of wheat buld in it to provide illumination. The building hides the one road fiddle yard, where the stock is upended to empty it of sand.

The sequence of stock is determined by a 5 digit Base 6 computing engine (oh alright 5 dice [die]). When thrown the resulting combination determines which engine to use, how many trucks/skips, the destination/s etc. All good fun for an hour or so/s operation.