sphericity

The belief in the sphericity of the earth carried with it of necessity another,—that the east was to be found in the west.

Such spheres had the advantage of lightness though often were frail in structure and liable to lose their perfect sphericity.

Suppose it is a question of having the pupil grasp the idea of the sphericity of the earth.

This is different from teaching him its sphericity as a fact.

The idea, not merely of the sphericity of the earth, but an explicit conception of the antipodes, is expressed.