Dredging, including the canal prism and the excavation of the sites of the bridge foundations, siphon and lock, averaged .2784 cents a cubic yard. The highest cost was in the lock section, from which 609,302 cubic yards were excavated at an average cost of .3796 cents a cubic yard. On the siphon and Florida Walk bridge section, including two other deep cuts, the 814,919 cubic yards excavated cost an average of .2607 cents a cubic yard. On the Louisville & Nashville bridge section, the 1,023,466 cubic yards excavated cost an average of .2363 cents a cubic yard. From there to the lake, 1,673,787 cubic yards, the average cost was .2411 cents. Dredging costs were below the original estimates when labor and supplies were 50 per cent cheaper. The 90,000 cubic yards of concrete in the lock cost an average of $22.50 a cubic yard. This includes cost of material, mixing, building forms, pouring and stripping forms. Mixing and pouring, from the time the material was handled from the storehouse or pile, averaged $1.20 a cubic yard. It would be hard to find cheaper concrete on a work of similar magnitude anywhere, say the engineers. On the siphon the concrete work cost more, because it was a subterranean job, with elaborate shaping. The price there was $35 a cubic yard, in place, including material and form work. To drive the 17,000 bearing piles and 7,000 traveling piles on which the lock is floated, cost an average of 15 cents a running foot. This does not include the cost of the piling. Construction steel cost .12 cents a pound, and erection around 4 cents. These were standard prices. The lock gates, weighing 5,285,000 pounds, cost $845,600, in place. This does not include opening and closing machinery. Three of the bascule bridges crossing the Canal, weighing 1,600,000 pounds each, cost $250,000 each, erected. The fourth bridge, near the lock, weighing 1,000,000 pounds, cost $200,000, erected. This is for superstructure only--it does not include the foundation. The emergency dam bridge, weighing 350,373 pounds, and its 108,256 pounds of turning machinery, cost $96,728, in place. Hoisting machinery cost $40,000 more. The eight girders of the emergency dam, weighing 90 tons each, at $240 a ton, cost $172,800. Machinery for working the ten lock gates, the eight filling gates, and the six capstans--twenty-four 52-horse power electric motors--cost $21,479, f.o.b. New Orleans. The plant for unwatering the lock, consisting of one pump with a capacity of 15,000 gallons a minute, and two with a capacity of 250 gallons each, cost, erected, $11,000. Total mechanical equipment used on the Industrial Canal weighs 14,500 tons. Its cost, including power-house, electrical connections, etc., is $1,516,000.