occupies so distinct and extended a position in the geological
structure of the globe. The chalk may be traced from the North of
Ireland to the Crimea, a distance of about 11,140 geographical miles,
and, in an opposite direction, from the South of Sweden to Bordeaux, a
distance of 840 geographical miles.

It extends as a broad belt across France, like the sash of a Republican
mayor. You may travel from Calais to Vendome, to Tours, Poitiers,
Angouleme, to the Gironde, and you are on chalk the whole way. It
stretches through Central Europe, and is seen in North Africa. From the
Crimea it reaches into Syria, and may be traced as far as the shores of
the sea of Aral in Central Asia.

The chalk is not throughout alike in texture; hard beds alternate with
others that are soft--beds with flints like plum-cake, and beds
without, like white Spanish bread.

We are accustomed in England to chalk in rolling downs, except where
bitten into by the sea, but elsewhere it is riven, and presents cliffs,
and these cliffs are not at all like that of Shakespeare at Dover, but
overhang, where hard beds alternate with others that are friable. These
latter are corroded by the weather, and leave the more compact
projecting like the roofs of penthouses. They are furrowed
horizontally, licked smooth by the wind and rain. Not only so, but the
chalk cliffs are riddled with caves, that are ancient water-courses.
The rain falling on the surface is drunk by the thirsty soil, and it
sinks till, finding where the chalk is tender, it forms a channel and
flows as a subterranean rill, spouts forth on the face of the crags,
till sinking still lower, it finds an exit at the bottom of the cliff,
when it leaves its ancient conduit high and dry.