Two stones contrast in New Penwith, 1974: One is squarish with a concave face
and large opening, while the other is more rounded, with a smaller hole in its convex surface.
The stretched fibers on the convex face tend to fracture long before the compressed concave face
reaches maximum stress limits.
The elastic membranes of their concave faces
pulse silently in hypnotic unison, transitioning from slow, soft bulging to quick, shallow popping in and out, like the rhythmic contractions of a diaphragm.
May 1, 2014 /PRNewswire-USNewswire/ -- Concave faces
, the result of underdevelopment of the middle of the face (midfacial hypoplasia) is a deformity in which growth of the upper jaw, cheekbones, and eye sockets lags behind that of the rest of the face.
Reducing slippage causes the formation of concave faces
in a specimen.