728 BULLETIN OF THE BUREAU OF FISHERIES. 



,4/ Battle Creek, Cal. — The main or upper rack at Battle Creek, Cal., is 

 constructed on a comparatively soft and shifty river bottom, and is supported 

 by piling, instead of by the log cribs anchored with rocks, more generally used. 

 There are 12 bents of piling, each bent consisting of 3 piles driven firmly and 

 braced with heavy timbers. The 3 piles comprising a bent are driven parallel 

 with the current, the front one standing some 2 feet above low-water mark and 

 the others about 8 feet above. The front and rear piles are placed about 10 

 feet apart. On these bents of piling and reaching across the stream are placed 

 three 12 by 12 inch stringers, against which are secured 4 by 4 inch slanting 

 supports, about 6 feet apart, the lower ends of which rest on a mud sill placed 

 in the bottom of the stream. Stringers and these supports are so placed that 

 the face of the rack will meet the current of the stream at an angle of about 60°. 

 The gratings of the rack are built in sections of varying length but of a uniform 

 width of 5^ feet. The slats for these gratings are of dressed lumber i by 3 

 inches, the sides set parallel with the current, the upstream edge convex. At 

 either side of the stream, in the shallower water, single sections of gratings 

 about 10 feet long extend from the bottom to the top stringer. In the deeper 

 portions of the stream two 6 or 8 foot sections of the gratings are used, one above 

 the other, with an opening between the upper and lower sections for convenience 

 during the lower stages of water in the removal, with rakes and hooks, of 

 rubbish and trash drifting downstream. When the water rises the closing of 

 this aperture is easily accomplished by knocking out the blocking between the 

 two, thus permitting the upper rack to slide down flush with the upper edge of 

 the lower section. The length of the rack from shore to shore is about 300 feet, 

 its vertical height above low-water mark being about 8 feet. During low water 

 the front is submerged to a depth of from 18 inches to 2 feet, but there are holes 

 considerably deeper behind the rack. A walk 2 feet wide is built on the top of 

 the rack. A half mile below the barrier is a retaining rack quite similar to the 

 one described for the Baird station. 



At Battle Creek the racks are usually installed during September in time 

 to intercept the fall run of salmon, and unless carried out by high water, remain 

 until the close of the work in December. Gratings, stringers, etc., are then 

 removed and stored for use another season. 



At Birdsview, ]Vash. — A permanent barrier at the Birdsview station, an 

 auxiliary of the Baker Lake station, in Washington, is of novel construction and 

 calls for more than passing notice. This barrier is located in a portion of Phin- 

 ney Creek where formerly there was a dam built for the purpose of obstructing 

 the passage of steel-head trout. When the dam washed out, a new channel 

 formed and the river bed was very much broadened. 



The first step in the construction of the new barrier was the laying of four 

 heavy log stringers across this new channel from the abutment on the north to 



