"Jack London was essentially self-taught. In 1883 he found and read Ouida's long Victorian novel Signa, which describes an unschooled Italian peasant child who achieves fame as an opera composer. He credited this as the seed of his literary aspiration.
After graduating from grammar school in 1889, Jack London began working from twelve to eighteen hours a day at Hickmott's Cannery. Seeking a way out of this gruelling labor, he borrowed money from his black foster mother Jennie Prentiss, bought the sloop Razzle-Dazzle from an oyster pirate named French Frank, and became an oyster pirate himself. In John Barleycorn he claims to have stolen French Frank's mistress Mamie. After a few months his sloop became damaged beyond repair. He switched to the side of the law and became a member of the California Fish Patrol.
In 1893, he signed on to the sealing schooner Sophia Sutherland, bound for the coast of Japan. When he returned, the country was in the grip of the panic of '93 and Oakland was swept by labor unrest. After gruelling jobs in a jute mill and a street-railway power plant, he joined Kelly's industrial army and began his career as a tramp.
In 1894, he spent thirty days for vagrancy in the Erie County Penitentiary at Buffalo. In The Road, he wrote:
""Man-handling was merely one of the very minor unprintable horrors of the Erie County Pen. I say 'unprintable'; and in justice I must also say 'unthinkable'. They were unthinkable to me until I saw them, and I was no spring chicken in the ways of the world and the awful abysses of human degradation. It would take a deep plummet to reach bottom in the Erie County Pen, and I do but skim lightly and facetiously the surface of things as I there saw them.""
A pivotal event was his discovery in 1895 of the Oakland Public Library and a sympathetic librarian, Ina Coolbrith (who later became California's first poet laureate and an important figure in the San Francisco literary community).
After many experiences as a hobo, sailor, and member of Kelly's Army he returned to Oakland and attended Oakland High School, where he contributed a number of articles to the high school's magazine, The Aegis.
Jack London desperately wanted to attend the University of California and, in 1896 after a summer of intense cramming, did so; but financial circumstances forced him to leave in 1897 and he never graduated. Biographer Russ Kingman says that ""there is no record that Jack ever wrote for student publications"" there.
In later life Jack London was a polymath with wide-ranging interests and a personal library of 15,000. volumes.