IOWA

1911:                  ? (Eastern company, fire that year)

1912, 1914-15:         Borreson

1913:                  Adams

1916-18 Type 1, 1919:  Western

1916-18 Type 2:        Borreson

1920, 1921 Types 1-2:  Adams

1921 Type 3:           Grimm

1922-25:               Adams

1926-on:               Iowa Prison