ating
materials and obstructions by a special corps of egoutiers.

For the _wagonnets de service_ in the larger sewers, an ingenious
arrangement is used,--on the little four-wheeled truck which runs on
rails along the edge of the central canal are laid two more sections of
railroad at right angles, and on these are mounted two more four-wheeled
trucks carrying each a rectangular little tank or receptacle, with a
rounded bottom. The outside rail, at each end, is blocked, so as to keep
these tanks in position while in transit,--when arrived at their
destination, the blocks are removed and the two run off on other rails
to be emptied. The Parisian sewers carry not only the drainage of the
streets and houses, but also all those various underground means of
communication which in other, and less well-ordered, municipalities have
each their own burrowing to do,--at the cost of infinite expense and
confusion. The water-pipes, the telegraphic cables, the telephone wires,
the pneumatic tubes for the postal service, and the piping for the
conveyance of motive power, are all sheltered in these underground
thoroughfares. So complete and well organized, indeed, are these egouts,
that that constant habitant of sewers, the rat, is being driven out of
them,--neither the black rat nor his enemy, the great Norway animal, can
find lodging and refuge in these cement-lined walls, as hard as steel.
The task of the hunter of rodents is greatly facilitated by all these
improved methods.

It is difficult nowadays to conceive the condition of the streets of a
mediaeval city, and Paris was no exception. Not only were they very
crooked--each householder building where he chose, with very little
consideration for the general alignment, badly paved or not at all,
unsewered and dark, but they were the receptacles for absolutely all the
refuse of the dwellings. The butcher, the baker, and the
candlestick-maker threw everything out of the windows, and nobody
carried it away. The first vaulted sewer was constructed in the reign of
Charles VI, in the Rue Montmartre, by Hugues Aubriot, _prevot_ of the
merchants; but the state of the public thoroughfares remained much as it
had been in the preceding century. The houses were built on the level of
the streets, and inundated at every violent shower, the choked-up
gutters refusing to carry off the sudden flood. Even the kings of France
struggled in vain against the universal infection,--"incommoded in their