of
Brazilian Ruby—is a distinct Gem, seldom chosen for jewelry, hut useful
for optical purposes. Of the several varieties, the only one
occasionally employed is that of a dark, olive-green tint. It is
discovered also red, and pink, as " rubeolite " ; blue, as indiolite ;
white, brown, and black. The red Tourmaline is that found in Ceylon,
and in Siberia, which is known in commerce as the " Brazilian Ruby " ;
for which stone it is sometimes sold in mistake. The green, and blue
varieties of Tourmaline are got from the Brazils, being occasionally
called the Brazilian Emerald, and Sapphire. Chemically each of the
Tourmalines contains silica, alumina, magnesia, oxide of iron, boracic
acid, some soda, and some fluorine. By taking into consideration the
physical, and the drug actions of these chemical elements, on the body,
and mind, when administered therapeutically, we may form some
conclusions about such influences for good, or evil, as the stones now
under notice are likely to exercise on sensitive subjects, when worn as
jewels, or otherwise externally applied. The said drug actions have
already been considered here, of these several constituents ; except as
regards Magnesia, Fluorine, Boracic acid, Potash, and Soda.
Magnesia is
the basic oxide of magnesium, which mineral, in one form or another, is
universally disseminated throughout the whole of the earth's crust.
Traces of it are, moreover, to be found in the ashes of all plants, and
it is present furthermore in almost all Natural Waters. As familiar
medicaments, carbonate of magnesia, and siilphate of magnesia (Epsom
Salts), are well known to everyone. The chloride of magnesium
corresponds pretty closely with chloride of sodium (common salt), and
it has been authoritatively supposed
