UNIVERSAL DREDGES 139 



ing chain is driven through steel spur and bevel-gearing by means 

 of friction clutches, which slip in the case of an excessive load on the 

 chain, and thus prevent breakage. The centrifugal pumps are 

 driven direct through claw couplings on the crank-shafting, and 

 are designed for a maximum speed of 150 revolutions per minute. 

 They are built up of steel plates and angles, renewable plates of 

 steel being fitted inside the casings. The latter are designed so as to 

 admit of the interior of the pump being easily inspected. The impel- 

 lers have four arms, also fitted with renewable wearing plates. The 

 suction is long enough to allow of dredging to a depth of 32.8 ft. 

 It is so fashioned that with the dredge steaming fully laden it can 

 be carried entirely above the water level. The discharge pipe from 

 the pumps is of rectangular section, and runs along almost the 

 whole length of the hopper. It is provided with sluice openings 

 corresponding to each section of the hopper. 



Six cabins are provided: one each for the engineer, the chief 

 dredgeman, the chief mechanical engineer, and two others for the 

 two assistants of each, while the sixth is reserved as messroom. 

 The accommodation for the crew is sufficient for the needs of ten men. 



The boat is lighted electrically by means of three 1000-candle- 

 power arc lamps, in addition to incandescent lamps in the cabins and 

 engine rooms and stokehold. 



The navigating bridge is placed in front of the funnel, and is fitted 

 with steam steering-gear engine, telegraphs, and the like. A single 

 foremast is fitted as shown in the figure. 



The results obtained on the official trials, made on behalf of the 

 Uruguayan Government on the Meuse, during a period of fifteen 

 days, are given below: 



Condition of Content. Actual Results. 



Dredging by bucket, output per hour 500 cu.m. 650 cu.m. 



Suction dredging, output per hour 1200 cu.m. 1800 cu.m. 



Speed 7 knots 8.2 knots 



Fuel consumption, per I.H.P. per hour 1 kg. 0.95 kg. 



