You know, when you first mentioned that system of tonal values, I thought you were referring to the famous "zone system" created by Ansel Adams, which is the standard technique for black-and-white photography...
http://www.normankoren.com/zonesystem.html#History
However, that was not invented until 1939/1940 -- over 30 years after Denman Ross invented his nine-step value scale!
To my photographer friends, to even suggest that Ansel Adams is not to be given full credit for the idea, well, that wouldn't be "European"; it would be heresy!