Some of the so-called lower animals take cognizance of vibrations that mean nothing to us.

Insects hear notes far above our dull ears.

Ants are susceptible to lights and colors unseen to our limited eyes.

The emperor-moth calls its mate--so says Fabre--by means of olfactory vibrations totally uncomprehended by us.

The universe is full of hues, tones, radiant phenomena that escape us, because our senses are not attuned to them." Steadily he spoke, and steadily the humming drone that filled the cabin kept its undertones that lulled, that soothed.