Effusion of blood into the nerve sheath, or into the internal or middle ear, causes transitory deafness, and the patient suffers from noises in the ear, giddiness, and interference with equilibration.
"Manual of Surgery Volume Second: Extremities--Head--Neck. Sixth Edition."
Alexander Miles Alexis Thomson
Therefore, Spencer passed to what he called "indirect equilibration."
"Herbert Spencer"
J. Arthur Thomson
In short, Spencer incorporated the characteristic Darwinian idea of Natural Selection operating upon a crop of variations, and thus securing by the survival of the fittest an indirect equilibration.
"Herbert Spencer"
J. Arthur Thomson