Here was something against which he could exert his utmost force. He
rejoiced in it, taking great lungfuls of air, bending his shoulders,
breaking through these outer defences of the North with wanton
exuberance, blind to everything, deaf to everything, oblivious of all
other mental and physical sensations except the delight of applying his
skill and strength to the subduing of the stream.

But Sam, patient, uncomplaining, enduring, retained still the broader
outlook. He, too, fought the water and the cold, adequately and
strongly, but it was with the unconsciousness of long habit. His mind
recognised the Forest as well as the Stream. The great physical thrill
over the poise between perfect health and the opposing of difficulties
he had left behind him with his youth; as indeed he had, in a lesser
sense, gained with his age an indifference to discomfort. He was
cognisant of the stillness of the woods, the presence of the birds and
beasts, the thousand subtleties that make up the personality of the
great forest.

And with the strange sixth sense of the accustomed woodsman Sam felt, as
they travelled, that something was wrong. The impression did not come to
him through any of the accustomed channels. In fact, it hardly reached
his intellect as yet. Through long years his intuitions had adapted
themselves to their environment. The subtle influences the forest always
disengaged found in the delicately attuned fibres of his being that
which vibrated in unison with them. Now this adjustment was in some way
disturbed. To Sam Bolton the forest was _different_, and this made him
uneasy without his knowing why. From time to time he stopped suddenly,
every nerve quivering, his nostrils wide, like some wild thing alert for
danger. And always the other five senses, on which his mind depended,
denied the sixth. Nothing stirred but the creatures of the wilderness.