shewn in the preceding chapters how universal is the love of Pearls,
and what a prominent position they occupy in the fashionable world for
purposes of decoration ; having alluded also to some of the ideas that
have at various times prevailed with respect to their origin, virtues
and significance, we are now led naturally to the consideration of the
principal sources whence our supply of these valuable gems is derived.
Pearls may be defined, in scientific language, as calcareous concretions, produced by certain shell-