hellfish and ate them as he gathered,
it was with eyes that roved everywhere for hidden danger and with legs
prepared to run like the wind at its first appearance. Through the
forest they crept noiselessly, Buck at the hairy man's heels; and they
were alert and vigilant, the pair of them, ears twitching and moving and
nostrils quivering, for the man heard and smelled as keenly as Buck. The
hairy man could spring up into the trees and travel ahead as fast as on
the ground, swinging by the arms from limb to limb, sometimes a dozen
feet apart, letting go and catching, never falling, never missing his
grip. In fact, he seemed as much at home among the trees as on the
ground; and Buck had memories of nights of vigil spent beneath trees
wherein the hairy man roosted, holding on tightly as he slept.

And closely akin to the visions of the hairy man was the call still
sounding in the depths of the forest. It filled him with a great unrest
and strange desires. It caused him to feel a vague, sweet gladness,
and he was aware of wild yearnings and stirrings for he knew not what.
Sometimes he pursued the call into the forest, looking for it as though
it were a tangible thing, barking softly or defiantly, as the mood might
dictate. He would thrust his nose into the cool wood moss, or into the
black soil where long grasses grew, and snort with joy at the fat earth
smells; or he would crouch for hours, as if in concealment, behind
fungus-covered trunks of fallen trees, wide-eyed and wide-eared to all
that moved and sounded about him. It might be, lying thus, that he hoped
to surprise this call he could not understand. But he did not know why
he did these various things. He was impelled to do them, and did not
reason about them at all.

Irresistible impulses seized him. He would be lying in camp, dozing
lazily in the heat of the day, when suddenly his head would lift and his
ears cock up, intent and listening, and he would spring to his feet
and dash away, and on and on, for hours, through the forest aisles and
across the open spaces where the niggerheads bunched. He loved to run
down dry watercourses, and to creep and spy upon the bird life in the
woods. For a day at a time he would lie in the underbrush where he could
watch the partridges drumming and strutting up and down. But especially
he loved to run in the dim twilight of the summer midnights, listening
to the subdued and sleepy murmurs of the forest, reading signs and
sounds as