The music box was probably invented about 1770 in Switzerland. The earliest music boxes were small enough to be enclosed in a pocket watch, but they were gradually built in larger sizes and housed in rectangular wooden boxes. A typical large music box had a comb of 96 steel teeth plucked by pins on a brass cylinder 13 inches (330 mm) long, and the cylinder could be changed to allow different musical selections. Changing and storing the cylinders proved cumbersome, however, and so in the 1890s they were replaced by a large-diameter metal disk (shaped and revolved somewhat like a phonograph record) with projections or slots on its surface to pluck the teeth. The disks, which reached 2.5 feet (75 cm) in diameter, could be easily changed, and disk music boxes had displaced cylinder models in popularity by 1900. By 1910, however, music boxes had been largely replaced by the phonograph. The music box is one of several idiophones (instruments whose sounding parts are resonant solids) that are plucked rather than vibrated by percussion.