William Robson Notman: Presbyterian Ministerial Directory, 1898, has William Robson Notman in Boulder, CA, USA.
LDS website: William Robson Notman (b. 1 Jan 1857) Clebrig, Caithness, Sutherland, Scotland,married on 26 Nov 1890 in Presbyterian, Christ Church, Warwick, Bermuda to Mary Archibald Frith (b. 7 Oct 1871)Longford, Warwick, Bermuda
1900 USA Census lists him and his wife Archie, as living in Chicago Ward 24, Cook,Illinois (arrival in 1893).
Mary 'Archie' Notman continued to travel between New York and Bermuda,every couple of years right up to 1939. The passenger lists have her first trip after her husband's death, arriving back in New York from Bermuda, 20 Oct 1909.
I know it isn't exactly what you are looking for but perhaps it will give you a place to start.K