AN APPARATUS FOR DETECTING THE ESCAPE OF NOXIOUS GASES FROM DRAINS
Year: 1880

page_text: LETTERS PATENT to Robert Harris Reeves, of Parkhurst, in the Isle of Wight,
Engineer, for an Invention of "AN APPARATUS FOR DETECTING THE ESCAPE
OF NOXIOUS GASES FROM DRAINS."
w
PROVISIONAL SPECIFICATION left by the said Robert Harris Reeves at
the Office of the Commissioners of Patents on the 5th November 1880.
ROBERT HARRIS REEVES, of Parkhurst, in the Isle of Wight, Engineer.
AN APPARATUS FOR DETECTING THE ESCAPE OF NOXIOUS GASES
DRAINS."
"
FROM
My Invention consists in an apparatus which will detect the existence and indicate
the amount of noxious gases arising from drains, and which will also shew when
such gases become dangerous to health.
The apparatus consists in a tube which is attached to the drain, the amount of
pressure being indicated by a column of liquid. This liquid is composed of a
chemical re-agent which on contact with the air from the drain will at once detect
the presence of noxious gas, and will at once shew on an indicator the amount of
pressure and at what period there is an escape of gas.
The tube is U shaped, and is fixed vertically in a suitable case. One extremity
is attached by a pipe to the drain. In the other extremity is inserted the indicator,
which is composed of a test paper prepared so as to be sensitive to the re-agents
after described.
The tube is partially filled with a chemical re-agent in solution which on contact
with "sewer gas" will at once indicate its presence. For this purpose I prefer to
use a solution of potassic permanganate acidulated with acetic acid, or a solution of
auric-chloride.
A graduated scale is attached to the tube to indicate the amount of pressure.
The action of the apparatus is as follows:-
When the apparatus is attached to the drain the pressure of gas from the drain

page_text: will cause the liquid to rise in the opposite arm of the U tube, the density or
dangerous amount of gas being indicated by the graduated scale and by the
discoloration of the test paper indicator by contact with the re-agent.
The quality of the gas will be indicated by the amount of discoloration of the
reagent in the U tube, and in order to determine the amount of discoloration a
separate tube containing a similar solution is attached to a convenient part of the
case of the apparatus.
When the liquid is discolored throughout it is an indication that there is an
escape of the "sewer gas." The pressure being equal at all outlets the escape of
gas shewn by the apparatus will be the same as at any traps connected with the
drain.

page_text: "
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Robert Harris Reeves in the Great Seal Patent Office on the 5th May
1881.
ROBERT HÁRRIS REEVES, of Parkhurst, in the Isle of Wight, Engineer.
'AN APPARATUS FOR DETECTING THE ESCAPE OF NOXIOUS GASES FROM
DRAINS."
My Invention consists in an apparatus adapted to detect the existence and also
to indicate the amount of noxious gases (vapour poisons and poisonous organic
germs) arising from drains, and which will also shew when such gases become
dangerous to health.
The apparatus consists of a tube, which I prefer to be formed of glass, and
which in use is attached to the drain, the amount or variation of pressure being
indicated by a column of liquid. The liquid I employ is composed of a chemical
re-agent which on contact with the air from the drain will detect the variation of
pressure of noxious gas, and will thus at once pneumatically shew on an indicator
applied the amount of pressure.
The tube I employ is U shaped, such as represented by Figure 1 of the Drawing.
This tube a is fixed vertically in a suitable case, the extremity a' thereof being
attached by an india-rubber or other suitable pipe to the drain. In the other
extremity as is inserted the indicator b, which is composed of test paper prepared
so as to be sensitive to the re-agent afterwards described.
The tube a is partially filled, say, up to the dotted lines c, with a chemical
re-agent in solution, which on contact with sewer gas from the drains will at once
indicate by change of color the presence of a noxious gas.
The chemical re-agent I employ consists of a solution of potassic permanganate
acidulated with acetic acid, or a solution of auric chloride, but other re-agents may
be employed.
A graduated scale attached to the tube as at d will indicate any variation of
pressure in the drains.
The action of the apparatus is as follows:-When attached to the drain pressure
of gas therein will cause the liquid c to rise in the arm a², the extent of pressure
being indicated against the graduated scale, whilst the noxious character of it will
be indicated by discoloration of the re-agent, and in order to determine the amount
of discoloration a separate tube e containing a similar solution c¹ is attached to a
convenient part of the case of the apparatus.
When the liquid or re-agent has become discolored throughout it is an indication
that there is an escape of noxious gas.
The extent of pressure being equal at all
outlets, the escape of gas shewn by the apparatus will be the same as at any
traps connected with the drain,
When it is necessary to fix the apparatus in places where the re-agent in solution
would be affected by frost the U tube is reversed, as shewn by Figure 2, and the
test paper wad A is used instead of the re-agent in solution, it being attached to
an india-rubber washer or disc B, the pressure being indicated by the guide c
working on a pivot, the pressure of the gas moving the wad, and the discoloration
of the same being similar to that of the reagent in solution.
In order to detect whether poisonous gases are generated and discharged from
any old cesspits attached to drains, or that the fittings are defective, so as to allow
the escape of gases, I seal both ends of the drain on which the apparatus is fixed,
then partially filling the drain with water the apparatus will at once indicate
whether the gas is generated otherwise than by the flow of sewage, or if any
defects or faulty construction exists which would allow the gas to escape.

page_text: Having thus described my Invention, and means which I adopt in carrying the
same into effect, I would have it understood that what I claim is the arranging or
combining parts forming an apparatus for detecting the escape of noxious gases
from drains, substantially as described.
In witness whereof, I, the said Robert Harris Reeves, have hereunto, set my
hand and seal, this Third day of May, One thousand eight hundred and
eighty one.
ROBERT HARRIS REEVES. (L.S.)