This pictures tells a lot. This is a view from the head tower looking at the trolley on the suspension cables. This trolley would ferry material including buckets of concrete over the dam building site. Below right is the concrete mixing plant. There concrete would be mixed and put into 8 yard pails on special rail road car pushed by a Dinky, which was electric operated which is out of sight below the hill. You can see some of the buckets sitting on the hill. The dinky would then push the car with 2 pails of concrete under the trolley line to be picked up and then ferried to the point of dumping into the forms. Concrete weighs about 3500# per yard so a bucket would weigh 28,000 # or 14 tons which was picked up by the trolley. Also below the trolley is a water inlet tube which will be installed in the concrete.