In the early 18th century the piccolo began to appear with one to four keys, and more were added as the century progressed. In the years that followed the piccolo s development mirrored that of the flute. In 1832 the Munich flutist Theobald Boehm invented a revolutionary mechanism for the flute and by the middle of the 19th century it had already found its way onto the piccolo. Nevertheless, piccolos with older key mechanisms remained in use into the 20th century.