FLUMES AND LOG SLUICES 399 



from 12 to 14 inches. The lengths are commonly 16 and 24 

 feet. 



Box Flumes. — These are used for lumber and dimension 

 stock (Fig. 123, C), shingle bolts, pulpwood and logs.^ They are 

 more expensive to construct than a V-flume because the greater 

 weight of water carried necessitates a heavier trestle. Where 



Fig. 124. — A V-Flume for transporting Mining StuUs. Montana. 



the water supply is abundant, boxes of this character are some- 

 times used for lumber transport. A box flume- in California 



^ See note on page 412. 



- This flume was started in 189 1 by the Fresno Flume and Irrigation Company 

 for irrigation purposes and now is 65 miles in length, connecting the sawmill at 

 Shaver with the planing mill and shipping depot at Clovis. Near the head the 

 flume box is rectangular and has sides 12 inches high and a width of 48 inches. On 

 the steep mountain pitches the sides are 32 inches high, and on the lower end 

 48 inches high. The maximum grade is 45 per cent and the minimum grade on 

 the flats 0.5 per cent. 



