3
OF engineering formulae.
TO SET OCT A RIGHT ANGLE WITH THE CHAIN.
Take 40 links on the chain, 30 links for the
perpendicular and 50 for the hypotheuuse.
For right-angled triangles, see Trigonometry.
Useful Numbers in Surveying.
For Converting Multiplier. Converse.
Feet into links. 1-515 •66
Yards links. 4-545 •22
Square feet n acres. •0000229 43560
Square yards acres. •0002066 4840
Feet miles. •00019 5280
Yards miles. •00057 1760
Chains miles. •0125 80
For Table of links and feet, see “ Links.”
CHAINING ON SLOPES.
A = Angle of slope with horizon.
T, *= Length of line chained on the slope.
I = Length of line reduced to the horizontal.
I = LL K = cos. A.
Table showing Values of K.
5
8
9
10
11
12
14
15
16
996
'994
'992
■99
■988
■985
K- A. K. A. K. A. K. A. K.
•982 o 17 •956 o 23 •92 o 29 •875 o 35 •819
•978 18 •951 24 •913 30 •866 36 •809
•974 19 •945 25 •906 31 •857 37 •799
•97 20 •94 26 •899 32 •848 38 •788
•966 21 •933 27 •891 33 •839 39 •777
•961 22 •927 28 •883 34 •829 40 •766