John Brown

I am looking for any help in finding my 2nd great grandfather. All I know is: John Brown born July 1829 Norway moved to San Francisco 1854 naturalized US citizen in 1857. Naturalization records apparently lost in 1906 San Francisco earthquake. He never used an initial in his name. died in Madera County, California 1908. He was a farmer/dairyman and worked in a lumber flume all his life, so does not seem to have a connection with the sea, as I see many Norwegians have.