The western side is steeper because the lines are closer together than the other sides of the hill.
Explanation:
Each contour line represents a 20ft increase in elevation. You can see the 600ft line labeled on the map, so the next one in is 620, and the one labeled "X" is 640.
Contour lines that are farther apart indicate a more gentle slope that is increasing its height over a longer distance. Just like a graph in math class, slope is "rise over run," so a flatter slope tells us that the height is increasing slowly. Close contour lines show us that the height is going up very quickly.
Local shear failure occurs when the shear stresses parallel to the grain, i.e. shear stresses acting in the longitudinal-tangential (LT) or longitudinal-radial (LR) planes, exceed the shear strength of the beam. The shear strength of a wood member is difficult to quantify.
