To Make An Eolian Harp
This instrument may be made by almost any carpenter: it consists of a
long narrow box of very thin deal, about five or six inches deep, with
a circle in the middle of the upper side, of an inch and a half in
diameter, in which are to be drilled small holes. On this side, seven,
ten, or more strings, of very fine gut, are stretched over bridges at
each end, like the bridges of a fiddle, and screwed up or relaxed with
screw pins. The strings must be all tuned to one and the same note,
and the instrument be placed in some current of air, where the wind
can pass over its strings with freedom. A window, of which the width
is exactly equal to the length of the harp, with the sash just raised
to give the air admission, is a proper situation. When the air blows
upon these strings, with different degrees of force, it will excite
different tones of sounds; sometimes the blast brings out all the
tones in full concert, and sometimes it sinks them to the softest
murmurs.