IMPROVEMENTS IN TRAPS FOR PRE- VENTING THE ESCAPE OF GASES FROM SEWERS AND DRAIN PIPES
Year: 1874

page_text: LETTERS PATENT to Frederick William Colls, of Erith, in the County
of Kent, for the Invention of "IMPROVEMENTS IN TRAPS FOR PRE-
VENTING THE ESCAPE OF GASES FROM SEWERS AND DRAIN PIPES."
Sealed the 15th December 1874, and dated the 3rd July 1874.
PROVISIONAL SPECIFICATION left by the said Frederick William.
Colls at the Office of the Commissioners of Patents, with his
Petition, on the 3rd July 1874.
I, FREDERICK WILLIAM COLLS, of Erith, in the County of Kent, do
hereby declare the nature of the said Invention for "IMPROVEMENTS IN
TRAPS FOR PREVENTING THE ESCAPE OF GASES FROM SEWERS AND DRAIN PIPES," to
be as follows:-
--
This Invention has for its object improvements in traps for preventing
the escape of gases from sewers and drain pipes.
gases from
With the traps now used for preventing the escape of
sawers and drains the water which seals the trap to some extent absorbs

page_text: sewer.
gases from the interior of the trap which is open to the sewer or drain,
and again gives off these gases from its surface in the outer part of the
trap so that the trap does not entirely prevent the escape of gas from the
To prevent this I employ a trap into which is introduced a
small quantity of hydrocarbon or other non-saponifiable oil which is
lighter than water, and I construct the trap in such a manner that when
water or liquid is passed through the trap into the sewer or drain the
hydrocarbon oil shall not be carried away along with it. To effect this
I make the limbs of the syphon trap much longer than heretofore usual,
and just below the end of the inlet into the trap I by preference fix a
disc against which any liquid entering the trap strikes and is deflected
in all directions against its sides, so that the liquid instead of being
carried with a rush through the trap passes through it quietly and does
not carry away along with it any of the oil, but the oil floating upon the
surface of the water remains in the trap. A small quantity of hydro-
carbon oil is thus at all times within the trap, and as from its nature it
will not absorb gases it acts as a perfect seal.
SPECIFICATION in pursuance of the conditions of the Letters Patent,:
filed by the said Frederick William Colls in the Great Seal Patent
Office on the 1st January 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, FREDERICK
WILLIAM COLLS, of Erith, in the County of Kent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Third day. of July, in the ycar of
our Lord One thousand eight hundred and seventy-four, in the thirty-
eighth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Frederick William Colls, Her special.
license that Ị, the said Frederick William Colls, my executors, ad-
ministrators, and assigns, or such others as I, the said Frederick
William Colls, 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

page_text: 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 TRAPS FOR PREVENTING THE ESCAPE OF GASES
FROM SEWERS AND DRAIN PIPES," upon the condition (amongst others) that
I, the said Frederick William Colls, my executors or administrators,
by an instrument in writing under my, or their, or one of their hands
and seals, should particularly 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 Frederick William Colls, do hereby
declare the nature of the said Invention, and in what manner the
same is to be performed, to be particularly described and ascertained
in and by the following statement thereof, that is to say:-
This Invention has for its object improvements in traps for preventing
the escape of gases
from sewers and drain pipes.
With the traps now used for preventing the escape of gases from
sewers and drains, the water which scals the trap to some extent absorbs
gases from the interior of the trap which is open to the sewer or drain,
and again gives off these. gases from its surface in the outer part of the
trap so that the trap does not entirely prevent the escape of gas from the
sewer. To prevent this I employ a trap into which is introduced a small
quantity of hydrocarbon or other none saponifiable oil which is lighter
than water, and I construct the trap in such a manner that when water
or liquid is passed through the trap into the sewer or drain the hydro-
carbon oil shall not be carried away along with it.
In the "Drawings hereunto annexed are shewn two examples of traps
suitable for effecting this object.
In the arrangement shewn at Figure 1 the interior of the trap is
divided into compartments by four partitions a, a, the inlet to the trap
is at b, and the outlet at c. d is a layer of hydrocarbon oil floating on
the top of the water in the first three compartments, the upper part of
the partitions which separate these compartments is perforated so that

page_text: the hydrocarbon may flow freely from one compartment to another.
When water or liquid is thrown into the trap at the inlet 6 it flows
through the trap in the direction shewn by the arrows and escapes by
the outlet.c. If any of the hydrocarbon is carried along with the liquid
from the first compartment into the second compartment of the trap it
has time to come to rest at the top of this second compartment and is
free to flow back again through the perforations at the top of the first
partition, so that it will not be carried away with the liquid, and the
liquid will pass from the second to the third compartment below the
layer of hydrocarbon, which will always remain floating above the water
passing through these compartments.
The trap shewn at Figure 2 is formed of a deep U bend with a funnel-
shaped inlet a, as shewn. Within this funnel head is an inner funnel b,
the upper part of which is perforated to some distance below the level of
the liquid in the trap. c is a layer of hydrocarbon oil floating upon the
surface of the liquid in the funnel inlet. When water or other liquid is
poured into the trap it passes down through the inner funnel and
through the central portion of the descending limb of the trap, and any
hydrocarbon carried down along with it will have time to escape from
the descending column of liquid and will rise up at its sides and pass up
between the two funnels. and through the perforations at the top of the
inner funnel.
°
I would remark that although I have shown two examples of traps in
which hydrocarbon liquid may advantageously be used, yet other con-
structions of trap may be employed in which provision is made for
giving time for the hydrocarbon to separate itself from any water or
liquid which may be passed through the trap, and to again rise to the
surface of the liquid in the trap inlet in order that the hydrocarbon may
be prevented from being carried away from the trap into the drain or
sewer.
Having thus described the nature of my Invention, and in what
manner the same may be performed, I would have it understood that I

page_text: 2. The employment of hydrocarbon or other non-saponifiable oil together
with traps constructed substantially in the manner herein described.
In witness whereof, I, the said Frederick William Colls, have
hereunto set my hand and seal, this Thirty-first day of December,
in the year of our Lord One thousand eight hundred and seventy-
four.
FREDERICK WILLIAM COLLS. (L.S.)
FREDERICK WILLIAM COLLS. (L.S.)