Up on the mountains the midday sun glared fiercely, but down in the valley near the swift-running stream it was cool and still. I stood listening until I heard a faint rustling of leaves—the only sound to betray the presence of the group of chimpanzees I was trying to approach.
Slowly and quietly, but making no attempt to hide, I moved toward the great apes until I was only 30 feet away. As I sat down, they watched me, staring rather hard, and a young female who had been lying on the ground climbed a little way up a tall fig tree.
One of the males stood upright to watch more closely. He was a superb specimen, standing about four and a half feet in height, his massive shoulders and bull neck suggesting the tremendous strength in his arms. He must have weighed a good 130 pounds, and he was strong enough to snap with one hand a branch so tough that a man would be hard put to break it with two.