"The Phonograph as a Wireless Detective," Literary Digest 63:8 (Nov. 22, 1918), p. 29.

HOW A TALKING MACHINE turned detective and solved a wireless mystery of the war, is told by a contributor to the "Scientific American" (New York, October 11). It appears that just before the retreat of the Germans from the Chemin des Dames position in 1918, the Allied Intelligence Department told the General Staff the exact positions which would be evacuated, altho all preliminary operations on the Berlin side were carried out with the utmost secrecy. Every movement up to the final withdrawal had been made at night, and even divisional commanders in the German ranks were ignorant of the extent of the retreat. Wireless told the story. The narrator goes on:

"No message telling this precious secret was intercepted. The Germans knew far too much to intrust this to errant ether waves. Yet from the enemy's use of wireless equipment the Allies obtained their positive information.

"The reasoning behind it was simple, but it was not until 1918 that either side used the process--perhaps for that very reason. Most communication in the front trenches is carried on by telephone.

"The trench phone equipment is costly. On the German side toward the end of the war it was likewise irreplaceable. Whenever the decision was reached to get out of a certain sector, the Huns had first to move out their home instruments, wires and stations. From the time this was started until it was fully accomplished, wireless played an increasingly important part. Every phone station gave place to a temporary wireless station, and the chatter, bluff and serious orders in code were sent in this manner for perhaps ten days previous to the final withdrawal.

"From previous experience, French, British and American spotters had become familiar with the coincidental increase in the number of wireless messages with the preparation for retreat. So, with this symptom well developed along a 64-kilometer front on the Chemin des Dames, they had no difficulty in marking off the sector, and even in guessing accurately concerning the time the retreat would begin. Needless to say Allied artillery made the evacuation as difficult as possible."

Another queer situation in the wireless department was known officially for months as the "Nauen-Madrid Buzz." In May, 1916, says the writer, it appeared for the first time, emanating from Madrid. It was a curious rustle of the spark unlike any message familiar to Allied operators, who of course looked upon it with suspicion and tried to make something out of it. For perhaps five seconds--and sometimes as long as twenty--this phenomenon would occur. Then no more for perhaps a week. Until Nauen developed the same strange quality the buzz was diagnosed simply as an odd manifestation of "static."

"But Nauen buzzed. Immediately all the wireless sharps in the Allied ranks tackled the problem.

"It is needless to detail the man theories which were held concerning this mysterious communication--for after the first weeks no one doubted that the buzzing was just this. The solution was reached through pure accident.

"In studying foe wireless--which is in code, if important--the practice is to take down the message on a phonograph record. Then it can be decoded at leisure. One of the many dozens of records of the Nauen-Madrid buzz was being run. A young radio officer was attempting to solve the mystery. The spring in the machine ran down, and as he wearily reached forward to wind the box again he stopped, chilled by the excitement of a discovery. With the cylinder revolving at a very low rate something that might be a rapid message in code clicked from the horn!

"Throttling down the speed adjuster on the phonograph, he ran the record as slowly as possible. His hunch was justified! There was certainly something there, though it went too fast to be caught.

"He wrestled with the problem overnight. Next day he rigged up an electric motor to run his blank cylinder record at a prodigious rate of speed. When the buzzing occurred it was caught. Then when the record was re-run at a moderate rate the message was there! It was decoded shortly, and proved to be part of an important description concerning the disposal of Allied troops.

"The secret was simply that at Nauen and Madrid each message was cut into a perforated roll. This was run through the sending apparatus at the speed of four hundred words per minute. Naturally it turned out to be a buzz to anyone not 'in the know.' At the opposite station they simply took it on the phonograph, and that was all there was to it.

"The Allies managed to trace down many spies through the requests made by Nauen. In addition to this a great deal of erroneous information was sent through channels by which it would reach Madrid, and thence Nauen. After this there was always a third party on the line whenever the Germans and their agents in neutral Spain got talking together."