2140 Les Miserables
ly as stated in 1663; five thousand three hundred fathoms.
After Bruneseau, on the 1st of January, 1832, it had forty
thousand three hundred metres. Between 1806 and 1831,
there had been built, on an average, seven hundred and fif-
ty metres annually, afterwards eight and even ten thousand
metres of galleries were constructed every year, in masonry,
of small stones, with hydraulic mortar which hardens un-
der water, on a cement foundation. At two hundred francs
the metre, the sixty leagues of Paris’ sewers of the present
day represent forty-eight millions.
In addition to the economic progress which we have in-
dicated at the beginning, grave problems of public hygiene
are connected with that immense question: the sewers of
Paris.
Paris is the centre of two sheets, a sheet of water and
a sheet of air. The sheet of water, lying at a tolerably great
depth underground, but already sounded by two bores, is
furnished by the layer of green clay situated between the
chalk and the Jurassic lime-stone; this layer may be repre-
sented by a disk five and twenty leagues in circumference;
a multitude of rivers and brooks ooze there; one drinks the
Seine, the Marne, the Yonne, the Oise, the Aisne, the Cher,
the Vienne and the Loire in a glass of water from the well of
Grenelle. The sheet of water is healthy, it comes from heaven
in the first place and next from the earth; the sheet of air is
unhealthy, it comes from the sewer. All the miasms of the
cess-pool are mingled with the breath of the city; hence this
bad breath. The air taken from above a dung-heap, as has
been scientifically proved, is purer than the air taken from