FLUMES AND LOG SLUICES 



411 



men patrol it, the greater number being required where the flume 

 crosses the Continental Divide on a very low grade. The daily 

 cost of operation is $90, an average of 77^ cents per thousand 

 feet. 



On the American Gulch flume ^ in the same section five men 

 are required on a flume about one mile long. Two men feed 

 the flume and three men act as patrols. The daily run averages 

 from 800 to 1 1 00 mining stulls and the cost of operation varies 

 from 80 to 95 cents per thousand feet. 



A box log-flume, in Oregon, three and one-half miles long, 

 handles an average of 150,000 feet daily. Ten men are required 

 to operate the flume and the cost is 25 cents per thousand for 

 labor and 5 cents per thousand for depreciation. 



NOTES TO CHAPTER XXIU 



Page 398. The log flume shown in Fig. 1 23, D, requires the following material per 

 mile for construction where the trestle legs are 7 feet in length. 



Page 399. .\ box flume 3I miles long for the transportation of logs is in use in 

 Oregon. The problem confronting the operator was to transport timber out of a 

 roUing plateau region down to a mill several miles distant. Owing to the rough 

 character of the country the cost of railroad construction was prohibitive. The 

 engineering problems encountered were not easy to solve because the water supply 

 during the lowest stages did not exceed 100 miners' inches and extraordinary 

 efforts had to be made to conserve it. Some canyons from which timber was to 

 1 See note on page 413. 



