resents a continuous series of rounded and gentle undulations,
exhibiting to the careless glance of the unobservant, and to the
uninitiated, one vast homogeneous mass of earthy and stony materials.

But when this wide spread, and apparently uninvestigable aggregation of
particles, comes under the scrutinizing _eye of science_, a beautiful
and systematic arrangement of undigenous formations are clearly
developed. Individually containing within themselves the marvellous and
decisive evidence of their comparative existence, in their present
relative positions.

Those "_medallions of Nature_," the fossils which they contain not only
furnishing us with a chronological knowledge of the progressive
formation of the Earth's crust, but recording in language the most
intelligible, what were the peculiar states, and characteristics of
animal and vegetable existences at the distinct, and distant epochs of
the World.

By the aid of these silent but eloquent intelligencers, we discover that
the strata which now constitute the table lands of Touraine, were among
the last, in the whole geological series, that emerged from the waves of
the Ocean. That, that grand instrument of transposition and renovation,
has in a general sense, ever since been restrained within its mighty
confines. And that at the time its waters last prevailed over these
regions now high and dry, many of the types of living testacea, etc.
were become identical with those of existing species.

Touraine, or the department of Indre-et-Loire, may be said to be the
grand repository of the _tertiary_ formations of central France. It
constitutes the southern divisions of the great _Paris basin_, formed by
a vast depression in the chalk, and which is about 180 miles long and 90
miles broad. This cretaceous or chalk basin terminates to the south a
short distance from Poitiers, where the oolites and certain other
formations older than the chalk, crop out from beneath it, and thence
forward, principally constitute the formations of the more southern
departments of the kingdom: and occasionally extend to the summits of
the gigantic Pyrenees.

The long range of rocky precipices often constituting rather lofty
escarpments, along the northern borders of the valley of the Loire, are
a portion of the extensive cretaceous formations which surround Paris.
In the vicinity of Tours and many other places where its strata are
alike exposed to view, many beautiful specimens of some of