264 



A TREATISE ON DREDGES AND DREDGING 



"The getting of the material, pumping and turning, make almost 



exactly two-thirds the cost, and getting rid of it, the other one-third. 



"Divided up according to different items of expenditure, it is: 



Payroll 1.7G1 cts. 



Coal 1.408 



Water 0.039 



Subsistence . 476 



Engine-room supplies . 098 



Miscellaneous supplies 0. 150 



Repairs and renewals 1 . 342 



33.39% 



26.69 



00.75 



9.02 



1.87 



2.84 

 25.44 



5. 274 cts. =100% 



"These dredges are able sea boats and stay at work in Ambrose 

 Channel in stormy weather, until it gets too rough to go to sea and 

 dump, turning in the trough of the waves. They cannot work 

 quite as fast in rough as in still weather, because the pipes have to 

 be lifted more frequently to prevent the ship riding over them. 

 When the weather gets too thick to see buoys and ranges work 

 has to be suspended. But the chief cause of delays has been due 

 to repairing. 



"The following table gives the relative importance of the different 

 causes of delay and lost time, being the record of two dredges working 

 eleven months each, July 1, 1905, to May 31, 1906: 



"The lost time due to repairs is the item which we are trying 

 to redvice now. The value of this time far exceeds the cash cost 

 of the repairs. During the last three months (March to May 31, 

 1906) each dredge has averaged 8908 cu.yds. of excavation per day 



