ical documents before mentioned. It is evident that, where
such accidents occur, the want of continuity in the series may become
indefinitely great, and that the monuments which follow next in
succession will by no means be equidistant from each other in point of
time.

If this train of reasoning be admitted, the occasional distinctness of
the fossil remains, in formations immediately in contact, would be a
necessary consequence of the existing laws of sedimentary deposition and
subterranean movement, accompanied by a constant mortality and
renovation of species.

As all the conclusions above insisted on are directly opposed to
opinions still popular, I shall add another comparison, in the hope of
preventing any possible misapprehension of the argument. Suppose we had
discovered two buried cities at the foot of Vesuvius, immediately
superimposed upon each other, with a great mass of tuff and lava
intervening, just as Portici and Resina, if now covered with ashes,
would overlie Herculaneum. An antiquary might possibly be entitled to
infer, from the inscriptions on public edifices, that the inhabitants of
the inferior and older city were Greeks, and those of the modern towns
Italians. But he would reason very hastily if he also concluded from
these data that there had been a sudden change from the Greek to the
Italian language in Campania. But if he afterwards found _three_ buried
cities, one above the other, the intermediate one being Roman, while, as
in the former example, the lowest was Greek and the uppermost Italian,
he would then perceive the fallacy of his former opinion, and would
begin to suspect that the catastrophes by which the cities were inhumed
might have no relation whatever to the fluctuations in the language of
the inhabitants; and that, as the Roman tongue had evidently intervened
between the Greek and Italian, so many other dialects may have been
spoken in succession, and the passage from the Greek to the Italian may
have been very gradual; some terms growing obsolete, while others were
introduced from time to time.

If this antiquary could have shown that the volcanic paroxysms of
Vesuvius were so governed as that cities should be buried one above the
other, just as often as any variation occurred in the language of the
inhabitants, then, indeed, the abrupt passage from a Greek to a Roman,
and from a Roman to an Italian city, would afford proof of fluctuations
no less sudden in the language of the