FLUMES AND LOG SLUICES 407 



lumber was used, which was worth $12 per thousand. The 

 first 24 feet of each bent was framed on the ground, the foot of 

 each batter post being laid on or near the mud-sill on which it 

 was to rest. Bracing was made from i- by 6-inch and 2- by 

 6-inch material. When ready, the bent was hoisted in place, 

 and set on the mud-sills by the aid of a block and tackle attached 

 near the top of the nearest bent. When in position it was 

 plumbed up and spiked to the mud-sill. A 2- by 6-inch by 16- 

 foot timber was then placed against the outside of each post and 

 securely nailed to it with 20-penny spikes. Fore-and-aft braces 

 (Fig. 125) were then nailed on until the top of the 16-foot post 

 was reached when another 2- by 6-inch by 16-foot timber was 

 set on top of the first post with a lap of 8 feet on the inner 

 one. More fore-and-aft braces were then placed. The addi- 

 tion of 2- by 6-inch by 24-foot scantling continued, with proper 

 bracing, until the cut-off height was reached. On the 15.75- 

 foot span a block and tackle was used on each batter post for 

 elevating the material when the height became too great for 

 handing it up. On the 23.5-foot span lines were also hung on 

 the rear bent to aid in raising the 24-foot fore-and-aft braces. 



The cut-off point of the bent was established only when sev- 

 eral hundred feet of trestle had been built. A wye level was 

 then placed on a staging built on top of a bent and the line of 

 levels established by it. The 2- by 6-inch caps were elevated 

 and placed in position as soon as the posts were cut off. 



Cross-bracing was put on after several hundred feet of trestle 

 was erected (Fig. 125). Bents exposed to the wind were also 

 strengthened by wire guys. 



The construction crew consisted of from six to eight men, four 

 of whom worked aloft continuously. On low work one man 

 handled and sent up all lumber and another was engaged in 

 framing the lower sections. 



The lumber was hauled as near as possible to the point where 

 it was to be used, and was sorted and piled where it could be 

 reached with the least delay. One man built the boxes in 16- 

 or 24-foot sections at the upper end of the flume, placed the 

 brackets inside each section, and placed it and the 4- by 6-inch 



