rkshire--a distance of over two hundred and eighty miles as the
crow flies.

From this band to the North Sea, on the east, and the Channel, on the
south, the chalk is largely hidden by other deposits; but, except in
the Weald of Kent and Sussex, it enters into the very foundation of
all the south-eastern counties.

Attaining, as it does in some places, a thickness of more than a
thousand feet, the English chalk must be admitted to be a mass of
considerable magnitude. Nevertheless, it covers but an insignificant
portion of the whole area occupied by the chalk formation of the
globe, which has precisely the same general character as ours, and is
found in detached patches, some less, and others more extensive, than
the English.

Chalk occurs in north-west Ireland; it stretches over a large part of
France--the chalk which underlies Paris being, in fact, a continuation
of that of the London basin; it runs through Denmark and Central
Europe, and extends southward to North Africa; while eastward, it
appears in the Crimea and in Syria, and may be traced as far as the
shores of the Sea of Aral, in Central Asia.

If all the points at which true chalk occurs were circumscribed, they
would lie within an irregular oval about three thousand miles in long
diameter--the area of which would be as great as that of Europe, and
would many times exceed that of the largest existing inland sea--the
Mediterranean.

Thus the chalk is no unimportant element in the masonry of the earth's
crust, and it impresses a peculiar stamp, varying with the conditions
to which it is exposed, on the scenery of the districts in which it
occurs. The undulating downs and rounded coombs, covered with
sweet-grassed turf, of our inland chalk country, have a peacefully
domestic and mutton-suggesting prettiness, but can hardly be called
either grand or beautiful. But on our southern coasts, the wall-sided
cliffs, many hundred feet high, with vast needles and pinnacles
standing out in the sea, sharp and solitary enough to serve as perches
for the wary cormorant, confer a wonderful beauty and grandeur upon
the chalk headlands. And in the East, chalk has its share in the
formation of some of the most venerable of mountain ranges, such as
the Lebanon.

* * * * *

What is this wide-spread component of the surface of the earth? and
whence did it come?

You may think this no very hopeful inquiry. You may not unnaturally
suppose tha