As the subsoil packed more solidly, this wilderness in time sunk beneath the waters. The Mississippi built up its sandbars again, storms shaped them above the waves, marsh grass raised the surface with its humus, and another forest grew. This, in turn, sunk. And so the process was repeated, time after time.
At different depths below the surface of the ground the remains of these forests are found today, the wood perfectly preserved by the dampness. And through this tangled mass the dredges had to fight their way.
It was a task too great for the ordinary type of 20 or 22-inch suction dredge, even with the strength of 1,000 horses behind it. When they met these giant stumps and trunks they just stopped.
A. B. Wood, of the sewerage and water department, had already designed and patented a centrifugal pump impeller adapted to the handling of sewerage containing trash. Learning of this, W. J. White, superintendent of dredging on the Canal, asked him to design a special impeller, along similar lines, for the dredge Texas.
Results from the invention were remarkable. During the thirty days immediately preceding the installation the dredge had suffered delays from clogged suction which totalled 130-3/4 hours. During the thirty days immediately succeeding installation the total of delays for the same reason was cut down to 71-1/2 hours. The average yardage was, for the earlier period, 152 an hour, of actual excavation; and for the later period, 445 an hour—an increase of almost 200 per cent. The situation had been met.
This was the period when the cost of labor and material began to jump. Employers were bidding against each other for men, and the government's work practically fixed the price of supplies.
George M. Wells, consulting engineer, in his report of December 9, 1918, to the Dock Board, summarized labor increases over the scale when the work was begun, as follows: Unskilled labor, 54%; pile driver men, 40%; machinists, 40%; blacksmiths, 40%; foremen and monthly, 15 to 40%—an average increase of 40%. Materials had advanced, he went on to show, as follows: Gravel, 72%; sand, 25%; cement, 10%; lumber (form), 70%; timber, 40%; piles, untreated, 40%; piles, treated, 25%. These increases, together with the expansion of the plans requiring a canal of maximum depth, instead of the pilot cut of fifteen feet, as originally planned; the insistence of the Levee Board that levees in the back areas must be raised to elevation 30; development of unforeseen and unforeseeable quicksand conditions in the various excavations; requirements of railroads for bridges of greater capacity and strength than needed; building of a power line to the Foundation Company's plant—not a Dock Board job, but one that the conditions required it should finance then; and other expenses, besides delaying the work, made another bond issue necessary to finish the job.
At its meeting of February 26, 1919, President Thompson laid the matter before the board. It decided to issue $6,000,000 of bonds, for which the same syndicate of bankers that had taken the other two offered 96. Liberty bonds were then selling at a big discount, and this seemed the best terms on which the money could be secured.
This gave a total issue of $12,000,000 to date, the interest on which amounted to $600,000 a year. The Levee Board raised its share of the "rental" to $550,000, to guarantee the interest; the Public Belt Railroad's $50,000 made the total complete.
In the meantime ships were beginning to bulk large on the ways of the Foundation and the Doullut & Williams yards. The Foundation company launched its first, the Gauchy—a 4,200-ton non-sinkable steel ship, built for the French government—in September, 1919; and the Doullut & Williams company launched its first, the New Orleans, a steel vessel of 9,600 tons, the largest turned out south of Newport News, built for the Shipping Board, in January, 1920. These were followed by four sister vessels from the Foundation yard and seven from the Doullut & Williams plant. The former went to sea through Bayou Bienvenu and the latter through Lake Pontchartrain. The Doullut & Williams yard is a large one. Originally planning a mere assembling yard, the Foundation Company had subsequently developed the greatest steel fabricating plant in the South—so confident it was that New Orleans would carry through the project.