[GreenKeys] Teledeltos Fax Paper

[Jim Haynes]

If you read the W.U. History of Technical Progress 1935-1945 (which is
also on the MIT site) you learn that they had different companies
involved in different stages of producing the paper, so as to keep
secret the details of the entire process.

I've never been near much of the stuff, but have heard that it produces
toxic fumes when it is being written.

If you read much about fax in the W.U. Technical Review it is, in
retrospect, tragic that they spent so much money developing practical
fax and then never got anything out of it when fax-by-telephone took
off in more recent years. (and drove the final nails in the coffin of
public telegrams)

W.U.                            Japanese
All-metal construction          Mostly molded plastic
Teledeltos recording paper      Thermal recording paper, or xerographic
    high voltage                    or impact-sensitive
Hardwired by private line       Public Switched Telephone Network
    to W.U. office                  (after Carterfone)
Manual fiddling with forms      Automatic sheet feeder
Multiple store-and-forward      Complete end-to-end connection
    operations through system       in real time
Slow, no compression            Microelectronics permitting compression
Small size image (Desk Fax)     Full letter size image, or greater
Vacuum tube technology          Integrated circuits

Or, in sum, W.U. had something of the right concept, but the technology
wasn't there yet.