Born in Stamford Township, Delaware County, New York, he left home in 1850 headed for the gold fields of California with his brother John. Hume panned gold and mined for a number of years in addition to operating a trade store off and on. In 1860 he began his career as a peace officer serving as deputy tax collector for El Dorado County, California. In 1864 he was elected City Marshal of Placerville, California, and in 1864 hired as Undersheriff of El Dorado County. He ran for Sheriff in 1865 and remained in office until 1870. In 1871 Wells, Fargo & Company hired him as a detective, but gave him a year's leave in 1872 to serve as deputy warden of the Nevada State Prison. He became one of the most prominent detectives of the times. He married Lida Munson on April 28, 1884, and had a son, Samuel James Hume. He never retired from the company, but after an illness in 1897 he slowed down and began working fewer road trips. He died at his home in Berkeley, California.