Second Empire, and in
conjunction with the Engineer-in-chief of the navigation of the Seine,
M. Belgrand, the present system was inaugurated. The latter found means
of solving the problem after a careful study, in 1854, of the basin of
the Seine. The bed of gypsum on which Paris is built furnishes neither
water of a good drinking quality nor sources high enough to bring it
into the city at the requisite altitude; it was therefore necessary to
go outside this basin, extending from Meulan to Chateau-Thierry. At
present, Paris is furnished with potable water by three aqueducts,--that
of the Dhuis, a hundred and thirty-one kilometres in length, constructed
from 1862 to 1865, running from a source nearly due east of the city;
that of the Vanne, a hundred and eighty-three kilometres, 1866-1874,
from the southeast, and that of the Avre, a hundred and eight
kilometres, 1890-1893, from the west. A fourth is to be built, of a
length of seventy-two kilometres, which will draw its supply from the
valley of the Loing and the Lunain, a little west of Vanne.

When the city was enlarged by the annexation of the surrounding
communes, in 1860, the municipal administration signed a contract with
the _Compagnie generale des eaux_, which then held similar contracts
with several of the communes both within and without the walls. By this,
the city obtained the control, not only of its own water-supply and
distribution, but also of that previously established by the company.
The general management of the distribution is in the hands of the
Compagnie, which collects the subscriptions, constructs branch pipes
from the public conduits to the facade of the dwelling to be served, and
turns the gross receipts into the municipal treasury, less its
commission. To it, or to the _bureaux d'inspection_, all complaints are
to be addressed. The purer _eaux de source_, brought by the aqueducts,
are reserved for domestic use; the _eaux de riviere_, from the Seine and
the Marne, are elevated to the altitude requisite to serve the higher
quarters of the city by eleven _usines_, within and without the walls.
The river-water is served by means of gauges and meters; the eau de
source by meters only, which are officially examined and verified by the
Municipal Laboratory, established in the Palais du Bardo, in the Pare
Montsouris. This laboratory also analyzes this water, that of the
drains, the sewers, and the wells, and reports to the municipal
administration. Wi