Baree, Son of Kazan by James Oliver Curwood

A moment later the factor from Lac Bain stood at the edge of the chasm. His voice had called out in a hoarse bellow -- a wild cry of disbelief and horror that had formed the Willow's name as she disappeared. He looked down, clutching his huge red hands and staring in ghastly suspense at the boiling water and black rocks far below. There was nothing there now -- no sign of her, no last flash of her pale face and streaming hair in the white foam. And she had done THAT -- to save herself from him!

The soul of the man-beast turned sick within him, so sick that he staggered back, his vision blinded and his legs tottering under him. He had killed Pierrot, and it had been a triumph. All his life he had played the part of the brute with a stoicism and cruelty that had known no shock -- nothing like this that overwhelmed him now, numbing him to the marrow of his bones until he stood like one paralyzed. He did not see Baree. He did not hear the dog's whining cries at the edge of the chasm. For a few moments the world turned black for him. And then, dragging himself out of his stupor, he ran frantically along the edge of the gorge, looking down wherever his eyes could see the water, striving for a glimpse of her. At last it grew too deep. There was no hope. She was gone -- and she had faced that to escape him!