Some Engineering Problems Of The Panama Canal In Their Relation To Geology And Topography

________ 78 ____ _____________________ ENGINEERING PROBLEMS OF PANAMA CANAL. BREAKWATERS. The Naos Island breakwater was charged with rhe difference between the cost of dumping material on some of the spoil banks near Balboa and the cost of placing it in the breakwater, including the charge for tracks, trestles, etc. During the fiscal year 1913, 653,137 cubic yards of material was placed in the breakwater, at an average cost of $0.2934 per cubic yard. During the fiscal year ended June 30, 1912, 460,040 cubic yards of hearting rock from Toro Point was placed in the Colon breakwater, at an average division cost of $1.3832 per cubic yard, including, of course, cost of quarrying, loading, transportation, and tracks and trestle out onto the breakwater. In addition to the soft heart material, hard coarse rock had to be used to face or annor the breakwater. This was procured at the Porto Bello quarry, a detailed statement of the cost being as follows: Detailed statement of cost of procuring coarse rock from the Porto Bello quarry for the Colon breakwater, 1912. Quantity of rock quarried, cubic yards...................................... 183, 762 Cost per cubic yard: Stripping.......................................................... $0.4178 ............................................................ ........................................................... Drilling..............................................................1087 Blasting..............................................................2259 Loading..............................................................________________1278 Transportation.........................................................1427 Tracks............................................................. . 3662 Loading on barges......................................................1956 Power....................................................................................................1257 Maintenance of equipment..............................................6287 Plant, arbitrary........................................................3203 Total per cubic yard................................................ 2. 6594 Cost of towing, per cubic yard : Operation of tugs and barges............................................2829 Maintenance of equipment..............................................1780 Plant, arbitrary.........................................................3916 Total...................................................................8525 ________ Cost of placing material, per cubic yard: Operation of floating derricks..........................................1716 Maintenance of floating derricks........................................0932 Operation of cranes...................................................1562 Operation of trains....................................................0741 Dumping............................................................0143 Maintenance of equipment............................................1453 Plant, arbitrary.......................................................1553 Total ............................................................... .8100 ________