IMPROVEMENTS IN VALVES FOR SEWERS OR DRAINS FOR PREVENTING OR ARRESTING THE PASSAGE OF NOXIOUS OR OFFENSIVE GASES
Year: 1872

page_text: LETTERS PATENT to Thomas Johnson, of Plumstead, in the County of
Kent, for the Invention of " IMPROVEMENTS IN VALVES FOR SEWERS OR
DRAINS FOR PREVENTING OR ARRESTING THE PASSAGE OF NOXIOUS OR
OFFENSIVE GASES."
Sealed the 13th August 1872, and dated the 14th February 1872.
PROVISIONAL SPECIFICATION left by the said Thomas Johnson at the
Office of the Commissioners of Patents, with his Petition, on the
14th February 1872.
I, THOMAS JOHNSON, of Plumstead, in the County of Kent, do hereby
declare the nature of the said Invention for "IMPROVEMENTS IN VALVES
FOR SEWERS OR DRAINS FOR PREVENTING OR ARRESTING THE PASSAGE OF NOXIOUS
OR OFFENSIVE GASES," to be as follows:-
My Invention of improvements in valves for sewers or drains has for
its object to prevent the passage of noxious or offensive gases from the
main sewer up into the branch sewers or drains, and from thence into
the houses or buildings which discharge their sewage into the drains.
This object is effected by adapting to the main sewer at any convenient

page_text: point in the vicinity of the discharge end of the branch sewer or house
drain a self-acting float valve, which by floating in the liquid sewage
in the main drain will prevent the passage of noxious gases but will not
arrest or materially interfere with the flow of the sewage.
The improved valve consists of a flat plate made of metal or other
suitable material and mounted in vertical guides fixed on each side of
the main sewer or drain. On the lower part of this valve plate is fixed
a float consisting by preference of a hollow metal vessel which will be
lifted or floated by the effluent sewage, and will consequently raise the
valve and allow the liquid to pass, while at the same time it will arrest
the gases. As the level of the sewage water rises and falls the float
valve will rise and fall with it, and will therefore be self-acting. In
order to prevent the valve from sticking in its vertical guides or grooves
antifriction rollers may be adapted thereto so as to reduce the friction of
the vertical plate in its guides.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Thomas Johnson in the Great Seal Patent Office
on the 14th August 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, Thomas
JOHNSON, of Plumstead, in the County of Kent, send greeting..
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fourteenth day of February, in the year
of our Lord One thousand eight hundred and seventy-two, in the thirty-
fifth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Thomas Johnson, Her special licence
that I, the said Thomas Johnson, my executors, administrators, and
assigns, or such others as I, the said Thomas Johnson, my executors,
administrators, and assigns, should at any time agree with, and no others,
from time to time and at all times thereafter during the term therein
expressed, should and lawfully might make, use, exercise, and vend,
within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN VALVES FOR
SEWERS OR DRAINS FOR PREVENTING OR ARRESTING THE PASSAGE OF NOXIOUS OR
OFFENSIVE GABES," upon the condition (amongst others) that I, the said.
Thomas Johnson, my executors or administrators, by an instrument in

page_text: writing under my, or their, or one of their hands and seals, should par-
ticularly describe and ascertain the nature of the said Invention, and
in what manner the same was to be performed, and cause the same to
be filed in the Great Seal Patent Office within six calendar months.
next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Thomas Johnson, do hereby declare
the nature of my said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by
the following statement, reference being had to the Drawing hereunto
annexed, and to the letters and figures marked thereon (that is to
say) :-
My Invention of improvements in valves for sewers or drains has for
its object to prevent the passage of noxious or offensive gases from the
main sewer up into the branch sewers or drains or from thence into the
houses or buildings which discharge their sewage into the drains. This
object is effected by adapting to the main sewer at any convenient
points (such as in the vicinity of the discharge end of the branch sewers
or house drains, and at various other points along the line of the main
sewer) a self-acting float valve, which by floating in the liquid sewage
in the main drain will prevent the passage of noxious gases, but will not
arrest or materially interfere with the flow of the sewage. By placing
thesc valves at various points along the main sewer the latter will be
subdivided into lengths of manageable dimensions, and the gases from
each subdivision may be carried off up a ventilating shaft or otherwise
dealt with more effectually than if the sewer were not so subdivided.
The improved valve and the mode of adapting it to a sewer or drain
is shewn in the accompanying Drawing, in which Fig. 1 is a sectional
plan view of a main sewer shewing the improved valve adapted thereto,
and shewing also the side entrance and descending shaft whereby access
is obtained to the sewer from the roadway above; Fig. 2 is a vertical
section of the same taken in the line A. B, of Fig. 1; Fig. 3 is
another vertical section taken in the line C, D, of Fig. 1 and at right
angles to that shewn at Fig. 2.
The improved valve shewn in the above-mentioned Figures consists of
a flat plate made of metal or other suitable material a which is mounted
in vertical guides b, b, fixed on each side of the main sewer or drain A
and in the vicinity of an upcast or ventilating shaft B. On the lower

page_text: part of this valve plate a is fixed a float c consisting by preference of a
hollow metal vessel, or it may be made of wood, cork, or other buoyant
material which will be lifted or floated by the effluent sewage, and will
consequently raise the valve a in its vertical guides and allow the liquid
to pass, while at the same time it will arrest the gases. As the level of
the sewage water rises and falls the float valve will rise and fall with it,
and will therefore be self-acting. In order to prevent the valve from
sticking in its vertical guides or grooves antifriction rollers may be
adapted thereto, as shewn in the detached sectional views, Figures 4
and 5, which represent one of the guides drawn upon an enlarged
scale.
In Figures 4 and 5, a represents part of the sheet-iron valve, and b, b,
the metal vertical guides in which it works. To the outer vertical
edges of the valve a are adapted the antifriction rollers d, the peripheries
of which may be covered with an india-rubber band. These anti-
friction rollers may be adapted in either of the ways shewn at Figures 4
and 5, their object being to reduce the friction of the vertical plate a in
its guides b, b, and to keep the valve in its proper position. In order
to prevent effluvium from passing round the edges of the valve strips
of vulcanized india-rubber e, e, are fixed on the face or edges of the
guides and are made to bear against the sides of the vertical plate a.
I have shewn the float c as adapted to only one side of the valve
plate a, but if desired a similar float may be adapted to the other side,
as indicated by dots in Figures 1 and 3. I find it convenient to adapt
to the upper edge of the valve plate a a rod or chain, as indicated by
the dotted lines at f, in Fig. 3, and this rod or chain will extend up to
the surface of the ground, so that should the valve plate a by accident
become temporarily fixed or be accidentally held down by mud or
accumulated debris so that it will not work easily in its guides it may
be lifted and worked up and down in order to free it and allow the
accumulated sewage to pass. If a rigid rod be used for this purpose the
valve may be held down so that it may be made to act as a sluice valve
and keep back the water until a sufficient head is obtained to scour the
sewer by the rush of water.
Having now described my Invention of "Improvements in Valves for
Sewers or Drains for Preventing or Arresting the Passage of Noxious or
Offensive Gases, and having explained the manner of carrying the same

page_text: into effect, I claim as the Invention secured to me by Letters Patent as
aforesaid, adapting to sewers vertical sliding valves provided with floats
for lifting the same as and for the purposes herein set forth.
In witness whereof, I, the said Thomas Johnson, have hereunto set
my hand and seal, the Fourteenth day of August, in the year of
our Lord One thousand eight hundred and seventy-two.