[Footnote 39: Cassiodorus, who quotes Tacitus to the Aestians,
the unlettered savages of the Baltic, (Var. v. 2,) describes the
amber for which their shores have ever been famous, as the gum of
a tree, hardened by the sun, and purified and wafted by the
waves. When that singular substance is analyzed by the chemists,
it yields a vegetable oil and a mineral acid.]