LOGGING IN THE DOUGLA-S FIR REGION. 193 



includes the cost of yarding the material to the track and building 

 the trestle, and also a rental of $5 per day on the equipment. The 

 bents consisted of three piles, the highest point on the trestle froni 

 the ground being 12 feet. Rough hemlock timber was used for 

 piling, caps, and stringers. 



Case 7. — The cost of building the following pile-bent trestle was 

 $389.05, or $2.28 per linear foot. This total does not include the 

 value of the timber used for piling, nor the value of the sawed caps, 

 stringers, and bracing. 



Structure. ^ 



Total length -feet__ 170 



Number of piles 39 



Average length of piling feet 20 



Average penetration of piling feet 10 



Sawed caps 7 



Sawed stringers, 8 by 16 inch Douglas fir. 

 Bracing, 300 feet b. m. (3 by 12 inch). 

 Alignment : 100 feet, 28° ; 70 feet tangent. 



Cost. 



Moving machinery to place $42. 77 



Yarding material to site _- 33. 75 



Driving piling 117. 36 



Placing stringers and caps 77. 46 



Laying track 18. 50 



Excavating- 17.12 



Surveying 19. 09 



Drift bolts, 200 pounds, at $2.25 per 100 pounds___i 4. 50 



Rent of equipment 58. 50 



Total 389. 05 



The cost of driving piling for pile-bent-trestle construction varies. 

 In one case piling was driven, cut off, a,nd capped at the rate of $1.86 

 per pile. 



The daily cost was as follows : 



Foreman $4. 00 



Engineer 3. 50 



Fireman 2. 75 



3 men, at $3 ^ 9.00 



Total labor cost 19.25 



Rental on equipment 10. 00 



Total cost 29.25 



Average daily output, 16 piles driven and capped. 



This trestle was 2,000 feet long and consisted of three-pile bents, 

 spaced 16 feet apart. It averaged about 10 feet in height, the pene- 

 tration of the piling averaging about 15 feet. 

 61361"— Bull. 711—18 13 



