82
molbsworth'» pocket-book
Roads Skirting
B=Width of base.
A=Area of section.
x — Angle of ground
with horizon.
y—Angle of slope
with horizon.
Sidelong Ground.
B
________
co tan, x — cotan. ?/.
Values of K for different
Angle
of
ground i to 1. itoi. Jtol. Itoi. i; to 1,
10 •0922 ■0967 •1016 •107 •1199
12 •1123 •119 •1265 •1351 •1562
14 ‘1329 ’•1424 •1533 •1661 •1992
16 •1543 •1672 •1794 •2008 •2512
18 ‘1766 •1937 •2145 •2407 -3164
20 * 2 ■2222 •25 •'2857 •4009
22 • 2252 •2538 •2907 ■3389 •5128
24 ’25 •2857 •3342 •4012 •6702
26 •2777 •3225 •3846 •4761 •909
28 •3067 •362 •4421 •5675 1'3123
30 •3373 •4058 •5091 •6830 2’1551
32 •3703 •4545 •5882 *8333
34 •4058 •5091 •6830 1-0373
36 •444 •5707 •798“ 1’3297
38 •4854 •641 •9434 1-7857
40 •5307 •7225 1-131 2’6041
42 •5807 •8183 1-385
44 •6364 •9345 1-754
46 •6983 1-0729 2’315
48 •7692 125
50 •8488 1-475
A convenient plan is to take the angles of the ground at contour pegs 100
feet apart and the base in feet. A table prepared for any given bage and
elope from the formula will give the contents for each length in
“ cubes ” (100 cubic feet) per “ line ” (of 100 lineal feet), without the neces-
sity for plotting the croas-aectioiui.