For those that are interested in the early history of the film industry, the first volumes (1929-1941) of "International Photographer" are now available online at http://www.archive.org (Type in Local 659 in the search field).
This publication was the forerunner to the "American Cinematographer". Don't be put off by the name, though. There are quite a number of articles dealing with the early development of film sound, for those that are interested in such stuff.
Major kudos to Dino Everett at the USC Cinema Archives, and David Pearce at the Internet Archive for taking on this effort.
--S