BUILDING AN UPPER TIER OF LOCKS
TRAVELING CRANES THAT BEAR THE BRUNT OF BURDEN CARRYING
Photo by Brown Bros.
THE FLOOR OF A LOCK
If we climb upon one of the empty flat cars we will see that upon the floor of the whole train, usually made up of about 20 cars, is stretched a stout cable attached to a heavy iron wedge like a snow plow which, while the train is loading, is on the end car. Hinged sheets of steel fall into place between the cars, making the train floor continuous from end to end. If we should accompany the train to the dump—say at the great fill at Balboa about twelve miles from the Cut—we shall find that when it has reached its assigned position a curious looking car on which is an engine which revolves a huge drum, or bull wheel, is attached in place of the locomotive. The end of the steel cable buried under hundreds of tons of rock and dirt is fastened to the bull wheel, the latter begins to revolve and the steel plow begins to travel along the train thrusting the load off to one side. One side of the flat cars is built up and the plow is so constructed that the load is thrown to the other side only. It takes from 7 to 15 minutes to unload a train by this device which is known as the Lidgerwood Unloader.
EXCAVATING WITH A MONITOR AS CALIFORNIANS DIG GOLD