In 1927 and 1928 Jan and Cora Josephine travelled throughout the USA, recording the journey in two books. There is now an excellent account by Bill Bryson of the events of 1927 in the USA, concluding with "Whatever else it was, it was one hell of a summer." The solo flight of Charles Lindbergh from New York's Long Island to Le Bourget Field in Paris, on May 20-21 of that year, figures prominently. At the moment Lindbergh landed a Paris friend of Jan and Cora Gordon, Myron Chester Nutting, was mid-Atlantic on a boat headed for New York where they later met up with the Gordons again before they left on their tour. See: http://janandcoragordonart.blogspot.com/2014/09/jan-and-cora-gordon-with-nuttings-in.html . As far as I am aware, this is the only extensive account of the Gordons by a contemporary of theirs. The Gordons also met with their friends Richard and Charlotte Perry in Southport, Connecticut, see: http://janandcoragordonart.blogspot.com/2014/12/jan-and-cora-gordon-richard-perry-and.html .
An article in the Pittsburgh Post Gazette of December 4th 1927 records a talk given by Jan Gordon at the Carnegie Lecture Hall under the auspices of the Pittsburgh University department of fine arts. ( http://lifeartearth.blogspot.com/2013/02/jan-gordon-shocks-in-modern-art-used-up.html ). The article mentions that "amongst their exploits was entertaining an Arabian sideshow at Coney Island with lightning artist sketches and with their guitars. They also entertained on a show boat on the Mississippi." The comment in their lecture about "no new shocks in modern art" was used in a later edition of "Modern French Painters": http://janandcoragordonart.blogspot.com/2014/05/jan-gordon-no-new-shocks-prophecy-in.html .