Figure 6.—Conversion diagram for degrees, per cent grade, feet per statute mile, and gradient
(a) Values of gradient from 1:10-1:1500; (b) Values of gradient from 1:100-1:5000
The inclination of the bottom is given as the tangent of the angle between the sloping plane and the horizontal expressed as a ratio of integers. These ratios are referred to as gradients. In Figure 6 slope values expressed in degrees, per cent grade, feet per statute mile, and gradient are compared. With a few exceptions all profiles are represented with a 40:1 vertical exaggeration. To facilitate judging the magnitude of slopes on these profiles, Figure 7 shows various gradient ratios at a 40:1 vertical exaggeration. Slope corrections have not been made to the soundings. Except in special cases such corrections would make insignificant changes in the 40:1 profile.
All distances are given in nautical or geographical miles (1 nautical mile = 6080 feet).
Figure 7.—Gradients from 1:5 to 1:8000 shown at a 40:1 vertical exaggeration
Most profiles reproduced in this paper are at 40:1 vertical exaggeration. This template is provided to aid the reader in judging slopes on these exaggerated profiles.