He plodded on for half an hour, when the hallucination arose again. Again he fought it, and still it persisted, till for very relief he opened his rifle to unconvince himself. At times his mind wandered farther afield, and he plodded on, a mere automaton, strange conceits and whimsicalities gnawing at his brain like worms. But these excursions out of the real were of brief duration, for ever the pangs of the hunger-bite called him back. He was jerked back abruptly once from such an excursion by a sight that caused him nearly to faint. He reeled and swayed, doddering like a drunken man to keep from falling. Before him stood a horse. A horse! He could not believe his eyes. A thick mist was in them, intershot with sparkling points of light. He rubbed his eyes savagely to clear his vision, and beheld, not a horse, but a great brown bear. The animal was studying him with bellicose curiosity.
The man had brought his gun halfway to his shoulder (человек донес ружье уже на полпути к плечу) before he realized (прежде чем осознал = чем до него дошло;
The man had brought his gun halfway to his shoulder before he realized. He lowered it and drew his hunting-knife from its beaded sheath at his hip. Before him was meat and life. He ran his thumb along the edge of his knife. It was sharp. The point was sharp. He would fling himself upon the bear and kill it. But his heart began its warning thump, thump, thump. Then followed the wild upward leap and tattoo of flutters, the pressing as of an iron band about his forehead, the creeping of the dizziness into his brain.