When Buck walked past that hundred meter line, he showed his strong love for Thornton. But he also won a thousand dollars. And now the three men could begin a new trip. They wanted to go to new and strange places, in the East. They wanted to leave the towns and cities, and to find some gold. When they said goodbye, their friends weren't happy. "Be careful!" their friends said. "You'll be in the wild for months, and it will be dangerous." But Thornton, Hans, and Pete weren't afraid. With a sledge, some dogs, and guns, they could live anywhere in the wild. And they could live happily away from other people for a long time. Month after month they walked. They went down new rivers and slept on new mountains. They felt strange, new winds. Every day they caught fish or small animals for food, and Buck loved this. He loved catching his food and he loved going to these new and exciting places. One day, they found a road through the woods. But it began, nowhere and ended nowhere. Another day, they found an old house in the middle of some trees. They found a gun and an old bed inside, but no people. They saw summer, fall, winter, and then spring again. And at the end of their trip, they found a wonderful place between two small mountains. There was a small river, and at the bottom of this river the men could see gold. The men worked hard, day after day. They took the gold from the bottom of the river and put it into large bags. And every day, they got richer and richer. But the dogs had no work, so Buck started to take long walks in the woods. He didn't understand this new place, but he felt very happy. He started to feel something strange inside, and sometimes he could hear something. It called to him. One night, he woke up suddenly. He could hear the call loudly, and it came from the woods. It was a long, sad howl and it didn't come from a dog. Buck jumped up and ran through the camp into the woods. He walked slowly through the trees and, in an open place, he saw a wolf. He walked slowly and carefully to the wolf. But the wolf was afraid of Buck and it quickly ran away. Buck ran after it and followed it through the trees. After an hour, the wolf understood. Buck didn't want to hurt him. They started to play. Then they ran for a long time. Buck followed the wolf. He was very happy with his new wolf-brother. They stopped at a river and had a drink. But when he saw the river, Buck remembered Thornton. He couldn't follow his new brother. He had to go back to the camp. So, he turned around and started to run back. But the wolf wasn't happy. For an hour, he cried and ran next to Buck. But Buck didn't stop. The wolf sat down and howled sadly. But Buck had to leave him. When Buck saw Thornton in the camp, he quickly jumped on him. He played games with him. "Where were you, you crazy dog?" laughed Thornton. For two days and two nights, Buck never left the camp, and he was always near Thornton. He followed him everywhere. Buck was next to Thornton when he slept. He stayed with him when he ate. He watched him at work. But then he heard the call in the woods again, and it was loud. Buck remembered his wild brother. He couldn't eat or sleep. Buck started to walk through the woods again, and he tried to find his new brother. But he didn't hear his sad howl again. Then Buck began to sleep in the woods at night, and he stayed away from the camp for two or three days. He fished in the river for food, and one day he killed a large, dangerous animal. It was a long and difficult fight but Buck won. He could live in the wild now, and he was strong, young, and intelligent. "Buck is the best dog in the world," said John Thornton one day to his friends. "Watch him walk." "Yes, he really is a wonderful animal," said Pete. "You know, you're right," said Hans. Buck