32 
BULLETIN 
U. S. DEPAETMEXT OF AGRICULTURE. 
firmly nailed over the joints on the outside, is much more satisfac- 
tory than the doubled 1-inch boards. It is contended that the 1-inch 
doubled box is not as rigid as the 1^-inch lining reinforced by the 
battens, and that the doubled box permits of a constant spring when 
heavy timber is passing through the flume. This causes the boards 
gradually to work apart and fill in between the two courses with 
bark and sediment, eventually causing the box to leak badly. 
Another contention is that in rehiring there is never a good solid 
foundation to nail to, and that the nails keep working loose and 
catching passing timber, causing jams. It is claimed that, by the 
use of the 1^-inch or 2-inch box lining reinforced by the battens 
nailed on from the outside, the element of "spring" is materially 
reduced. 
ADVISABLE METHOD OF NAILING. 
In the construction of either type of box or the nailing on of the 
battens, the nails should, whenever possible, be driven from the 
outside and clinched on the inside of the box with the point of "the 
nail turned down the flume. By so doing the nails become tighter 
as the inside of the box wears, since the flumed material strikes the 
nails and drives or draws them in harder. When the inside of the 
box is so badly worn that it is necessary to replace the lining, the new 
lining furnishes a solid substance through which to nail. Each style 
of construction has its particular merits, and the prospective opera- 
tor should decide for himself which is more applicable to his needs. 
Tables showing approximate amount of material necessary to con- 
struct flumes of different sizes follow: 
Table 1. — Weight of water in a 16-foot section of flume when filled to various depths. 
Weight of 
Weight of 
Weight of 
water in a 
water in a 
water in a 
Slant depth. 
section of 
Slant depth. 
section of 
Slant depth. 
section of 
flume 16 
flume 16 
flume 16 
feet long. 
feet long. 
feet long. 
Inches. 
Pounds. 
Inches. 
Pounds. 
Inches. 
Pounds. 
20 
1,390 
34 
4,010 
48 
7,990 
22 
1,680 
36 
4,490 
50 
8,670 
24 
2,000 
38 
5,010 
52 
9, 360 
26 
2,350 
40 
5,540 
54 
10, 100 
28 
2,710 
42 
6, 110 
56 
10,900 
30 
3,110 
44 
6,740 
58 
11,700 
32 
3,560 
« 
7,300 
60 
12, 500 
