The heaving and Undulatory motion of an earthquake produces frequently considerable changes at the surface of the ground, besides an alteration of level.
"Geology"
James Geikie
It was said that the phenomena of interference and diffraction could not be explained by the theory of emission, while the Undulatory theory gave a simple explanation.
"The Mechanism of Life"
Stéphane Leduc
If we submit to a critical examination the various experiments which have established the Undulatory theory of light, we find that they do indeed demonstrate the periodic nature of light, but in no wise prove that light is a vibratory movement of the ether.
"The Mechanism of Life"
Stéphane Leduc