For the high speed radio photograms, where only blacks and whites are
needed, a corona glow lamp of very high frequency has been developed.
This lamp is lighted by the plate current of the last tube of the
amplifier; and as the lamp can be lighted and extinguished a million
times a second, it is obvious that the permissible speed is almost
limitless, and a thousand words per minute is believed ultimately
possible.
This lamp has been developed for the author by Professor D. McFarlan
Moore, an expert in lamps incorporating this phenomena, and who some
years ago, it may be remembered, produced a lamp of this type more than
two hundred feet long. It is probably safe to predict that no other lamp
will ever be able to compete in speed.
As photography is the quickest means of copying anything; and radio the
swiftest in travel, it seemed logical that the two hitched together
should constitute the most rapid means of communication possible.