"Glory to God in the highest and on earth peace to men of good will," Fessenden read aloud.
There doesn't seem to be an original recording available of the show, but you can listen to a recreated version of it here.
Fessenden's voice transmission to the public was the first of its kind. Until then, even though the telephone was already three decades old, Morse code was still the lingua franca among wireless operators like those on board ships owned by the United Fruit Company, whose crews were among those to hear Fessenden's inaugural broadcast.
Fessenden put years of research into developing radio technology. His theory? By boosting the power of the radio signal, he might be able to achieve a steady wave on a single frequency that could carry sounds. Here's how one observer from the American Telephone Journal described the contraption that Christmas Eve:
Speaking broadly, wireless telephony by this system is accomplished by generating a practically continuous succession of electromagnetic waves, modifying the character of the emitted impulses by means of sound waves without interrupting their continuity, and receiving them in a constantly operative receiver of suitable form which controls a local circuit containing a battery and a telephone receiver. The apparatus which was seen in successful use at the time of the recent tests is the result of a series of diligent investigations in which a large amount of work was done to show the necessity of rejecting plans which did not lead to the required quality of transmission.
Fessenden needed a massive tower to broadcast his signal. Partnering with a couple of wealthy Pittsburgh financiers, he built a 400-foot tower at Brant Rock capable of sending out an audio signal at tens of kilohertz — a much higher frequency than the spark transmitters of the day.
Radio has since become an ordinary technology. But this is where it all began — 107 years ago today.