It was well known to the ancient Chaldeans.

It was known to Moses and his followers; it was practised in perfection by Christ and His disciples.

To modern civilization it may seem a discovery, because the tendency Of all so-called progress is to forget the past.

The scent of the human savage is extraordinarily keen--keener than that of any animal--he can follow a track unerringly by some odour he is able to detect in the air.
Again, he can lay back his ears to the wind and catch a faint, far-off sound with, certainty and precision, and tell you what it is.

Civilized beings have forgotten all this; they can neither smell nor hear with actual keenness.