And Black’s obit is here:
http://www.nytimes.com/1993/05/11/obituaries/algernon-black-leader-of-society-for-ethical-culture-is-dead-at-92.html
He had ties to Eleanor Roosevelt.
A bit more on the US version of Rosa Luxemberg here:
http://en.wikipedia.org/wiki/Encampment_for_Citizenship