_Cracked Glass._--Some years ago, being a schoolboy at the time, I spent
my Christmas holidays at my grandfather's house in Somersetshire. The
members of the family were assembled for evening prayer, when suddenly
music, resembling that of an Æolian harp, was heard, produced apparently
by some person upon the lawn immediately beneath the window. As soon as
the prayers were concluded I opened the hall door, and was greatly
surprised to find the musician had departed. On returning to the
drawing-room I was informed that the moment I had left the room the
music ceased. Believing that some village friend had come to serenade
us, we drew our chairs round the fire in expectation of his return. A
few minutes only elapsed when the music was again distinctly heard. A
second visit was made to the hall door, but with no better success. It
was then resolved to open the shutters, which was no sooner done than
the mystery was clearly explained. During the day a pane of glass had
been cracked, and the music was produced by the two pieces of glass
vibrating against each other. We found, from repeated experiments, that
it required the atmosphere of the room to be at rather a high
temperature to produce the effect, for the moment the door, or one of
the other windows, was opened, the vibration ceased. I have only to add
that the music was very pleasing to the ear, and consisted of rapid
cadences. I have often mentioned the circumstance, but I never found any
one who had met with a similar _musical fracture_.