268 A TREATISE ON DREDGES AND DREDGING 



shell machine. The total number of cubic yards excavated was 

 91,230, which included 793 stumps and three large logs. The average 

 cost for the half year including all repairs and every expense properly 

 chargeable to dredging, but making no allowance for depreciation 

 of plant, is between 3 and 4 cts., or about one-tenth of the lowest 

 contract price (.35J) that I have ever paid for work in this locality, 



" The machine is now in thoroughly good order, and I see no 

 reason why it could not run six months longer without any general 

 overhauling. 



"In soft material the capacity is fully 2000 yds. a day, and we 

 have exceeded 1500 yds. on several occasions, when the proportion 

 of stiff clay to the ordinary marsh mud was not excessive; the 

 stumps seemed to offer no resistance to her work, as she generally 

 pulled the bucket right up through them, splintering the solid wood 

 so much that they would fall through the bucket. On one or two 

 occasions when we unfortunately brought the whole stump out it 

 stuck in the bucket and gave some trouble. The greater portion 

 of the delay was caused by excessive stickiness of the clay, which 

 would remain in the bucket sometimes several minutes after the 

 bottom door was opened before it would fall through. " 



The amount of work together with a detailed report of the sup- 

 plies consumed during a month by the dipper dredge " Alpha, " 

 of 1 cu.yd. capacity while working on the Raritan River was given 

 by Mr. E. L. Sugram as follows : 



"During the month of September, 1889, the U. S. Dredge 'Alpha' 

 has been working in the Raritan River, making a 10-ft. channel 

 out of a 7-ft. one. The material removed is light shale and gravel. 

 The actual time worked was 207 hrs., and the amount dredged 12,050 

 cu.yds. The best day's work was 750 cu.yds., and the worst 300 

 cu.yds. The machine is not worked very hard on account of an 

 insufficient number of scows in the plant. The following supplies 

 have been consumed during the month: 



Line 350 Ihs. 



Lard oil 12^ gals. 



Black oil 13 gals. 



Cylinder oil Ill ^l*. 



Grease 119 Ihs. 



Cotton waste 8} Ibs. 



Coal 41} tons 



Water M,500 gals. 



Kerosene 12$ gals. 



