Undulatory Theory.

Chambers's Encyclopaedia, Volume 10: Swastika to Zyrianovsk and Index, p. 365

Undulatory Theory. See articles INTERFERENCE, LIGHT, OPTICS, POLARISATION, PHOSPHORESCENCE, REFLECTION, REFRACTION, SOUND, SPECTRUM, WAVE, and literature there cited; also Basset's Physical Optics (1892).

Source scan(s): p. 0386