History of Yolo County, California: with biographical sketches of the….
By Tom Gregory (1913) http://books.google.com/books?id=PnAUAAAAYAAJ
It was sixty-three years ago, on the 3rd of April, 1849, that twenty-nine men started from McDonough county, Ill., enroute to California. Of that party probably only two are now living, David Harris, now of San Francisco, and David Hamilton, the subject of this sketch…..The trip was made overland with ox teams and required six months and was attended by many disagreeable features, which, however, were speedily forgotten by the travelers upon reaching their destination. From Single Springs where the little company separated….