COST DATA 267 



In addition to the hydraulic dredge, the following auxiliary 

 floating plant is employed : A gasoline launch, length over all 30 ft. 

 li in., 7 ft. beam, depth 3 ft. 3 in., propelled by a 16 H.P. " standard " 

 engine. Also 9 pontoons, each 35X10X3 ft.; 15 pontoons, each 21 

 ft. 3 in. X 10 X3 ft.; 1 water boat, 34 ft. 9 in. X10 ft. X4 ft. 6 in.; 1 

 oil boat, 34 ft. 9 in. X10 ft.X4 ft. 6 in.; 1 derrick boat, 29 ft. 6 in.X 

 10ft. 7 in.X 3 ft. 10 in. 



The original cost of the dredging plant was as follows : 



20-inch suction dredge $99,453 



Gasoline launch 1,733 



Discharge pipe line for dredge 3,023 



Rubber sleeves 1,275 



Pontoons and barges 6,501 



Skiffs. . 154 



Ill 



The following example illustrates the cost of dredging with 

 dipper dredges of small capacity: 



Capt. Frederick V. Abbot, Corps of Engineers, U. S. A., while in 

 charge of the improvement of the harbor of Charleston, S. C., thus 

 described the cost of the work of the dredge " Santee." The machine 

 was built by the Osgood Dredge Co. of Albany, N. Y., with a boom 

 50 ft. long and the dipper of If cu.yds. capacity. 



" In regard to the cost of the work, I quote the following figures : 

 Work began November 21, 1893. 



November 5,572 cu.yds. mud, 7 stumps cost $512. Average 7 cts. 



December 15,721 cu.yds. mud, 220 " 



January 13,628 cu.yds. mud, 628 " 



February 12,000 cu.yds. mud, 53 



March 29,996 cu.yds. mud, 138 



April 14,313 cu.yds. mud, 



690. 4 



456. " 3 



945. " 8 



470. " 1 



265. " 2 



"Work was suspended April 30, 1894. The total result of the 

 work is as follows : 



"Six thousand and seventy-five linear feet of canal have been 

 completed between 50 and 60 ft. wide and between 6 and 7 ft. deep 

 at low water, through the marsh, which is between 4 and 5 ft. above 

 low-water level. The material consisted largely of exceedingly 

 hard and sticky blue clay in which large cypress stumps were bedded. 



"The material was harder than any I have encountered any- 

 where else in the district, and could not be handled at all by a clam- 



