I've never seen a National. Produced between 1916 and 1918 they are described as "ornate".

For more information:

• Check out Peter Hunn's book .
• And be sure to check Arlan Carter's book that is specifically on rowboat motors when it comes out soon(2006).
• Don't forget the The Outboarder Achives posted by Skip Hagerman.
  Keep in mind that much information thought correct at one time has been revised as more literature and more motors have been discovered and studied.