| 摘要 |
<p>A calling device has a pair of rectangular, substantially coextensive planar flexible members hinged together along corresponding edges thereof with one member being offset with respect to the other so that when they are folded together a lip projects from the device. The members are bowed along their longitudinal axis, with a small bow at the end adjacent the lip and a larger bow at the opposite end. The concave sides of the members oppose each other to form a double-tapered cavity transverse to the longitudinal axis of the members. An endless elastic band surrounds the lip to provide a reed element at the entrance to the cavity.</p> |
