IMPROVED MEANS FOR REMOVING SMOKE AND FOUL AIR FROM TUNNELS AND OTHER PLACES
Year: 1882

page_text: PROVISIONAL SPECIFICATION left by John Nepomuc Mocrath at the Office
of the Commissioners of Patents on the 30th October 1882.
JOHN NEPOMUC MOERATH of Rome in the Kingdom of Italy, temporarily of
Finsbury Pavement in the City of London, Civil Engineer, "IMPROVED MEANS
FOR REMOVING SMOKE AND FOUL AIR FROM TUNNELS AND OTHER PLACES."
The object of this invention is to satisfy a long felt want of the public with
reference to the sanitary ventilation of tunnels and other places.
In applying my invention to the ventilation of tunnels, for example, I propose to
exhaust the smoke and gases of combustion therefrom in a simple and expeditious
manner as soon as they are emitted by a passing train, or immediately afterwards.
To this end I line the walls and roof of the tunnel with sheets of galvanized
iron or other suitable material, rivetted screwed or otherwise fastened together and
supported by brackets rods or stays at such a suitable distance from the wall
surface as will permit the train to pass freely. This lining to the tunnel may be
about 1 inch from the side walls near their base, and may arch over at top so as to
be only a few inches from the smoke-stack of the passing trains, leaving a
considerable space between it and the crown of the tunnel.
Within this top space and longitudinally of the tunnel I suitably arrange one or
more smoke removing channels according to the number of lines of rail, and 1
connect these longitudinal channels with the side spaces behind the lining to
the walls of the tunnel by transverse passages. These longitudinal channels are
preferably arranged immediately above and in line with the direction of the passing
train, and may be of about the diameter of the funnel.
The smoke removing channels are connected at suitable points with ventilating
tubes or up-casts, preferably situate at the ends of the tunnel, one set (where a
double line of rails is employed) for the up, and another for the down trains
respectively.
In cases where a single line of rails only is used, one half of the ejectors are
inclined in one direction and the other half in the other direction.
The draught thus created is strengthened by a series of smoke ejectors or cones
for conducting the air in the tunnel into the longitudinal channels. The nozzles of
these ejectors are pointed in the direction in which the train is travelling and

page_text: they are connected by the transverse passages above alluded to with boxed off
portions of the space behind the lining of the side walls, these boxed off portions
being preferably of tapering or pyramidal form in face view, and having their front
plates perforated.
Through these perforations the vitiated air will be sucked out from the lower
parts and sides of the tunnel, while the smoke and gases from the funnel of the
passing train will be immediately exhausted and carried away by the long smoke
channel and up the shafts at the end thereof to the upper air; fresh air being drawn
in from the ends of the tunnel to supply their place.
By the adoption of these simple, speedy and efficient means for ventilating
tunnels, persons of weak lungs will be able to travel by underground lines without
suffering any inconvenience from bad air and gases, while railway companies will
greatly benefit by the increased traffic resulting from the purity of the air on their
lines, and this with comparatively small outlay.
I would also remark that this novel application of smoke-removing channels and
ejectors may be used for the cure of smoky chimneys without difficulty. The
ejectors in this case may be fitted to the side or back walls of the stove or grate,
and be pointed upwards at an inclination, pipes within the flue serving to create an
upward draught and being so arranged as not to interfere with the sweeping of
the flue.