We wonder-is this the only business in the world that needlessly
burns electric lights in broad daylight?
MAURICE KANN, 1928

There are no simple technologies. Even the tools and materials used to make inventions are themselves objects and processes with histories. Peter Wollen, for instance, has observed that film and sound editing were transformed by the seemingly insignificant introduction of Scotch brand transparent tape.¹ Now tape editing has replaced the cement film splicer. The "sound apparatus" embraced by Hollywood in the late 1920s was not a simple machine, but a many-faceted assortment of equipment and applications, not all of which worked in harmony.² To refine the point a bit more: none of the competing sound systems in the 1920s was simply an autonomous device (like a newly invented lens). Rather, theatrical sound was a new configuration of many existing...