Dr. Adolph Sommer, the chemist who developed "Viscol" and owned the Viscol Company, was murdered Oct 20, 1933 in front of his chemical manufacturing plant in Cambridge, Middlesex Co., Massachusetts. He was born 1852 in Berlin, Germany; arrived in the United States in 1872; was naturalized in 1876; received is doctorate at the University of California, Berkeley in 1879, was an assistant instructor in Chemistry at U.C. Berkeley 1884-1890. Then, somewhere between 1890 (the last record of his association with U.C. Berkeley) and 1910 (the first census I could locate showing his residence as Cambridge, Massachusetts) he relocated from California to Massachusetts and started his company.

I've located Adolph Sommer in 1880, 1910, 1920 Census enumerations, and I've found many, many newspaper accounts of his murder.

Has anyone found his whereabouts in 1900 and 1930? That information would help me account for more of residence locations.

I'm also looking for his immigration record to corroborate the arrival year of 1872 found in the 1910, 1920 census enumerations.

Thanks so much for any help.

Jean