Jack London 
The Call of the Wild [EPUB ebook] 

This American classic is the gripping story of Buck, half St Bernard, half sheepdog, who is stolen from his comfortable Californian home and taken to the Klondike in the gold rush as a sled dog. Unputdownable and deeply moving, this story was written by Jack London after he worked in the gold rush in 1897. London was born in San Francisco, and he grew up on the waterfront in Oakland. Much of his youth was spent on the wrong side of the law.