He heard the clatter of concrete mixers, the raucous grind of the crusher, the scream of donkey engines and the shouts of foremen.
Men worked with graders and concrete mixers on highways and on bridges across small rushing streams.
The batter, stirred in drums like concrete mixers, was poured on with cranes and spouts.
The train, with two big 2-cubic-yard buckets, drew up alongside two concrete mixers.
A special equipment was required to haul the sand, gravel, and cement from the storage piles to the concrete mixers.
On the emptying sides of the concrete mixers there were other little electric railway tracks.