tensive excavations. A lane of fifteen or twenty feet was cut
through the stone, and the material was carted away in heavy square
blocks. Piers were left, at short intervals, to sustain the
superincumbent earth; and, in the end, the place gets to be a succession
of intricate passages, separated by these piers, which resemble so many
small masses of houses among the streets of a town. The entire region
around Paris lies on a substratum of this stone, which indurates by
exposure to the air, and the whole secret of the celebrated catacombs of
Paris is just the same as that of this quarry, with the difference that
this opens on a level with the upper world, lying in a hill, while one
is compelled to descend to get to the level of the others. But enormous
wheels, scattered about the fields in the vicinity of the town, show
where shafts descend to new quarries on the plains, which are precisely
the same as those under Paris. The history of these subterranean
passages is very simple. The stone beneath has been transferred to the
surface, as a building material; and the graves of the town, after
centuries, were emptied into the vaults below. Any apprehensions of the
caverns falling in, on a great scale, are absurd, as the constant
recurrence of the piers, which are the living rock, must prevent such a
calamity; though it is within the limits of possibility that a house or
two might disappear. Quite lately, it is said, a tree in the garden of
the Luxembourg fell through, owing to the water working a passage down
into the quarries, by following its roots. The top of the tree remained
above ground some distance; and to prevent unnecessary panic, the police
immediately caused the place to be concealed by a high and close board
fence. The tree was cut away in the night, the hole was filled up, and
few knew anything about it. But it is scarcely possible that any serious
accident should occur, even to a single house, without a previous and
gradual sinking of its walls giving notice of the event. The palace of
the Luxembourg, one of the largest and finest edifices of Paris, stands
quite near the spot where the tree fell through, and yet there is not
the smallest danger of the structure's disappearing some dark night, the
piers below always affording sufficient support. _Au reste_, the
catacombs lie under no other part of Paris than the Quartier St.
Jacques, not crossing the river, nor reaching even the Faubourg St.
Germain.

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