230 A TREATISE ON DREDGES AND DREDGING 



veyor being 102 ft. between centers. As originally installed it was 

 only 90 ft., but it was found necessary to lengthen it. All the 

 electric motors were manufactured by the Westing-house Co. 



"When all drivers are being used 225 H.P. is needed, but this 

 seldom occurs. The main drive motor, which operates the bucket, 

 line and ladder hoist, is in use nearly all the time. The starboard 

 winch motor is used more or less intermittently, only when it is 

 necessary to raise and lower the spuds, or the stacker, or swing 

 the dredge from side to side. The pump motors are used constantly 

 in supplying water for the revolving screen and tables, also for the 

 bucket washing apparatus, where the buckets jump at inversion 

 at the upper tumbler. Both revolving screen and stacker belt 

 motors are constantly in use, the one driving the revolving screen 

 or "grizzly," as it is commonly termed, for properly screening the 

 gravel, the other in connection with the stacker belt, which carries 

 off the tailings. The digging buckets average speed is about 22 

 buckets per minute, this naturally varying according to the nature 

 of the ground. 



"From 90,000 to 110,000 K.W. hours are used per month on the 

 dredge, making a daily rate of from 3000 to 3666 K.W. hours. 

 The cost of current is 1 cent per K.W. hour. 



" The entire cost of this dredge ready for operation was $90,000. 



"Such a dredge is operated during a monthly average of from 

 80 to 90 per cent of the possible running time. The dredge is operated 

 24 hours per day, with the three 8-hour shifts. All stops of whatever 

 nature are counted in the average time made; for breakdowns of 

 machinery, power shutdowns, and for cleaning up. A clean-up 

 is made twice a month usually taking up four or five hours. The 

 time is not lost entirely, as it is taken advantage of to make needed 

 repairs. To obtain such running results, duplicates of all wearing 

 parts must be kept on hand to be replaced with the least possible 

 delay. 



"Such a dredge is operated by two men, one being a winchiium. 

 the other an oiler. Many of the dredges employ a shoreman to <liii 

 deadmen and help in handling the shore line. In addition to these 

 most of the dredges carry a dredgemaster. 



"The wages paid to the men are as follow-: 



Dredgemaster $150 . 00 per month 



Winchman 3 . 50 per day 



Oiler 2.50 " 



Shoreman.. 2.00 " 



