The Whipple Museum of the History of Science in Cambridge has a webpage about some parabolic sound mirrors to reflect and focus sound.
This apparatus consists of a pair of brass parabolic reflectors mounted on wooden stands. One of the reflectors has a bracket with a hook for hanging a pocket watch. The demonstrator would use this apparatus to show how the sound of a ticking watch may be heard at a considerable distance having first been made into a beam, projected over a distance and refocused. Very little is known about this pair of mirrors in the Whipple’s collection. It is thought that they were made in France or Germany during the second quarter of the nineteenth century.
Source: Whipple Museum of the History of Science