deposit much matter in empty spaces in the interior of the earth. In
addition to the materials thus introduced, stalagmite, or carbonate of
lime, drops from the roofs of caverns, and in this mixture the bones of
animals washed in by rivers are often entombed. In this manner we may
account for those bony breccias which we often find in caves, some of
which are of high antiquity while others are very recent and in daily
progress. In no district are engulfed streams more conspicuous than in
the Morea, where the phenomena attending them have been lately studied
and described in great detail by M. Boblaye and his fellow-laborers of
the French expedition to Greece.[1045] Their account is peculiarly
interesting to geologists, because it throws light on the red osseous
breccias containing the bones of extinct quadrupeds which are so common
in almost all the countries bordering the Mediterranean. It appears that
the numerous caverns of the Morea occur in a compact limestone, of the
age of the English chalk, immediately below which are arenaceous strata
referred to the period of our greensand. In the more elevated districts
of that peninsula there are many deep land-locked valleys, or basins,
closed round on all sides by mountains of fissured and cavernous
limestone. The year is divided almost as distinctly as between the
tropics into a rainy season, which lasts upwards of four months, and a
season of drought of nearly eight months' duration. When the torrents
are swollen by the rains, they rush from surrounding heights into the
inclosed basins; but, instead of giving rise to lakes, as would be the
case in most other countries, they are received into gulfs or chasms,
called by the Greeks "Katavothra," and which correspond to what are
termed "swallow-holes" in the north of England. The water of these
torrents is charged with pebbles and red ochreous earth, resembling
precisely the well-known cement of the osseous breccias of the
Mediterranean. It dissolves in acids with effervescence, and leaves a
residue of hydrated oxide of iron, granular iron, impalpable grains of
silex, and small crystals of quartz. Soil of the same description
abounds everywhere on the surface of the decomposing limestone in
Greece, that rock containing in it much siliceous and ferruginous
matter.

Many of the Katavothra being insufficient to give passage to all the
water in the rainy season, a temporary lake is formed round the mouth of
the chasm, which then