_Key Experiments_ (Vol. v., p. 152.).--Perhaps J. P. Jun. may not be
aware that an experiment somewhat similar to these is practised in the
Isle of Man. The operator holds a thread between the finger and thumb,
with a shilling fixed horizontally to it, gradually drops the shilling
into a glass, and after it has once become stationary, the shilling
begins to oscillate, and, as the superstition goes, invariably strikes
the hour of the day against the glass. I have frequently practised it,
and consider the motive power to be the pulse, which is completely under
the operator's control. This performance has been known in the Isle of
Man certainly more than a century, and bears a resemblance to the
experiments of Mayo and Reichenbach with the Od Force, or the vagaries
of the Magnetoscope.
Perhaps some of your correspondents can instance cases and tricks of
this kind of much earlier date.