I picked up this 20 page booklet on ebay. It apparently is a reprint of newspaper and magazine clips by the Shortwave and Television magazine.
It includes electronic and mechanical TV. Of particular interest is a number of clips that describe demonstrations of mechanical TV-telephone demonstrations held at various department stores, fairs, car dealers, etc. in various cities. One of the articles mentions that it was produced by the American Institute of Television of Chicago. It says the machines were first displayed in Germany.
(5.8 MB pdf file)
http://www.bretl.com/tvarticles/docu...television.pdf
More on ATI, the hardware, and its proprietor, Ulysses A. Sanabria, is on the earlytelevision.org site:
http://www.earlytelevision.org/ati.html