Recording Sound Before Anyone Could Hear It Back

[A] Twenty years before the phonograph, a Parisian printer built a machine that wrote sound down. A membrane carried a bristle resting on paper blackened with lamp soot, and a turning drum drew the paper past it, so a voice left a thin wavering line. [B] The inventor never tried to turn the line back into a sound, and it is a mistake to call this an oversight. His model was photography, which had lately made it possible to keep an image without the thing, and what he wanted was a written form of speech that the eye could study at leisure. [C] The traces were filed as curiosities and stayed there for a century and a half. [D]

In 2008 researchers photographed the sheets at high resolution and treated the line as a set of instructions, converting its rise and fall into pressure and then into sound. A woman's voice came out of them, singing. The point worth taking from this is not that the printer was cheated of his fame. It is that the sound had been present in the paper the whole time, and the thing that was missing was not information but a way of reading it. Instruments record what their makers are looking for, and what else they may be holding is a question only a later question can ask.