Solar heat, b. [145].

Solstitial points, a. [131].

Solution of water in air, b. [166].

Sothic period, a. [118].

Spagiric art, b. [262].

Specific heat, b. [159].

Sphere, a. [130].

Spontaneous generation, b. [457].

Statical electricity, b. [208].

Stationary periods, a. [48].