Part 9/15:
An example compares how a wave near the observer can block a ship far away, similar to how my thumb can hide the Moon when held at arms length. However, this analogy only applies if the wave is directly in line with the object; small waves can't block large ships unless they're directly in the line of sight.
Surface Roughness and Obstruction
In reality, uneven terrain or water ripples can partially obscure objects, but the consistent bottom-up disappearance observed in ships traveling over open water aligns more closely with Earth's curvature than with random wave effects.