COST OF DREDGING. 375 



the most severe ordeal to which a dredger can be put to, cost 

 18'03 pence per cubic yard. 1 



On the Clyde Navigation, the average cost of two years' 

 work, 1870-72, of dredging in sand, silt, clay, and gravel, was 

 3'86 pence per cubic yard, including all working charges, and 

 10 per cent, interest and depreciation on the original cost of 

 plant. 



Transporting the dredged material by steam hopper-barges 

 a distance of twenty-seven miles, and depositing, cost, taking 

 the mean of two years' work (1870-72), 5 '29 pence per cubic 

 yard, including all working charges, and 10 per cent, interest and 

 depreciation. 



Total average cost of dredging and transporting a distance 

 of twenty-seven miles (1870-71), 9*15 pence per cubic yard. 2 



Liverpool. 3 Dredging with a steam hopper-vessel of 1000 

 tons capacity, fitted with Priestman's cranes and grabs, and 

 conveying seven to eight miles to sea, cost 1*78 pence per ton, 

 exclusive of interest and depreciation. This rate is divided as 

 follows : 



Pence. Per cent. 



Wages 081 = 45'50 



Coals 0-31 = 17-42 



Repairs and maintenance 066 = 37*00 



1-78 9992 



1 M.P.LC.R, vol. Ixxxix. p. 110; and Engineering, vol. xliv. p. 278. 



8 M.P.LC.R, vol. xxxvi. pp. 161, 163, 169. 3 Engineering, vol. xlvii. p. 406. 



