412 



LOGGING 



be transported had no available water in them and it was necessary to build the 

 flume from one watershed to another to get the timber out. 



The preliminary work consisted of a survey of the whole route and a very careful 

 determination of the levels. The construction work was begun at the mill and 

 carried forward each year as required to secure the requisite amount of timber. 

 The first section of the flume was built nearly on a dead level, but as the work 

 progressed a grade of i inch in loo feet was given. 



The natural gradient greatly exceeded that given to the flume and it was neces- 

 sary to build the latter in three units, each ending in a V-shaped chute which led 

 from the flume to a pond at a lower elevation. These ponds were about 75 by 100 

 feet in size and were located at points where the natural conditions favored their 

 construction. They not only served as a storage reservoir for water and a point 

 for the change in grade of the flume but also as a place for logs to enter the flume. 



The grade line was kept as near the ground as possible in order to avoid expen- 

 sive trestle work and cuts. However, some cuts could not be avoided and trestles 

 had to be built when the flume crossed canyons or other depressions. 



The flume box was constructed of 2- by 1 2-inch plank and was 6 feet wide and 

 4 feet deep, except on sharp curves where it was wider. The normal depth of the 

 water was 3I feet. Trestles were built of sawed timbers and braces of the same 

 size timbers were placed along the box at 3-foot intervals. A running board 

 extended along one side of the box for the use of flume tenders. Lumber for 

 building the flume was cut in a portable mill which was kept as near the actual 

 construction point as was practicable. This reduced the charge for transport of 

 flume material. Each flume unit was provided with three lift gates suspended 

 from the center of a beam which was supported by two upright posts placed on 

 either side of the flume. One gate was used for the control of the water and the 

 other two for emergency purposes. Should an accident happen to the gate in 

 use, or a log become jammed in it, one or both of the others could be closed and a 

 waste of water prevented. The gates were opened by lifting them with a lever 

 until they cleared a 2-inch cleat nailed across the bottom of the flume when the 

 force of the water raised them to a horizontal position. They were then supported 

 by 2- by 4-inch joists, which were placed across the flume. 



In the spring of the year an abundance of water was available and a slight 

 current was created in the flume by keeping open a small extra gate. During this 

 season the logs were floated loose and only an occasional man was needed to keep 

 them moving and to prevent jams. In the summer and fall the water was at a low 

 stage and the logs were dogged together in strings of from 50 to 75 (10,000 to 15,000 

 feet, log scale) and were towed along the flume by a man who traveled the running 

 board. The opening of the large gates also created an artificial current which 

 assisted in keeping the logs moving. The tow was kept as near the gate as possible 

 and when the latter was opened the logs were rushed through to get the maximum 

 benefit from the accumulated head. 



The flume was built at a cost of $3,000 per mile and it is estimated that with 

 minor repairs, it will last for fifteen years. 



It will handle a 50-inch log, or two 30-inch logs side by side, except where the 

 latter pass through the gates. The logs run three to the thousand feet, log scale, and 

 the average daily capacity of the flume is 150,000 feet. Twenty-four million feet 

 have been handled in seven and one-half months. 



