Hotchkiss left the Russell Military Academy in June 1848, just before he was 17 years old. He went to work for his older brother Thomas as a clerk and bookkeeper. His brother had taken over their father's lumber yard in New Haven the year before. Prompted by the California gold rush, Hotchkiss went to that state in the spring of 1849. The 154-day sailing trip from the east coast involved going around Cape Horn, the southernmost tip of South America where the Atlantic and Pacific oceans meet. The voyage ended in San Francisco with many other gold-seekers, who were known as "forty-niners". In California he worked as a clerk of a general store in Sacramento for about a year, then opened the first trading post in the Greenwood Valley near Sacramento in early 1850. In that year he was one of the signers of the petition for California statehood application.