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56 THE MAGIC OF JEWELS AND CHARMS
explain these phenomena, even although the explanation is faulty.
The great French crystallographer, Abbé Haüy, relates his experiments on a tourmaline crystal.98·
He set this crystal in steel clamps, with a long stem which was
inserted in a wooden handle, and then subjected the tourmaline to the
heat of a brasier. As the heat augmented and penetrated the stone, its
natural electric force became decomposed, the two component fluids
being forced to separate from each other. It was now necessary to cool
the tourmaline off a little ; when too much heated the electrical
phenomena were interrupted; they were also diminished in intensity when
the stone became cool again. The perfect crystal chosen for experiment
clearly showed the negative and positive electrical poles; even the
smallest pieces showed this, and, indeed, if a very small piece were
broken off the positively electric side of a crystal, it would preserve
this positive electricity and soon develop a negative electricity also.
We
may be somewhat loath to doubt the tale that little Dutch children were
the first to note what to them was the queer action of some bits of
tourmaline, but preference should probably be given to the statement
that the discovery of the electric phenomena induced by heating in
these stones was due to the fact that some Dutch jewellers put
specimens of tourmaline in the fire to test their hardness, and then
found that the stones attracted or repelled the ashes of the fire."
Toward
the middle of the eighteenth century Dr. Haber-den, of London,
confirmed the deductions of Lémery and the somewhat later experiments
of the German physicist Aepinus, and the gay world of London took up
the idea,
"*
Abbe Hauy, " Trattato dei caratteri fisici delle pietre preziose,"
Ital. trans, by Luigi Configlfachi, Milano, 1819, pp. 135-138; see
Plate II, fig. 49. "Aepinus, 1. e.
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