IMPROVEMENTS IN THE VENTILATION OF SEWERS
Year: 1869

page_text: LETTERS PATENT to Arthur Jacob, Civil Engineer, of Bromley, in
Kent, for the Invention of "IMPROVEMENTS IN THE VENTILATION OF
SEWERS."
Sealed the 17th August 1869, and dated the 20th February 1869.
PROVISIONAL SPECIFICATION left by the said Arthur Jacob at the
Office of the Commissioners of Patents, with his Petition, on the.
20th February 1869.
I, ARTHUR JACOB, Civil Engineer, of Bromley, in Kent, do hereby
declare the nature of the said Invention for "IMPROVEMENTS IN THE
VENTILATION OF SEWERS," to be as follows:-
Instead of the ordinary man-hole and lamp-hole covers used in
sewerage works, and which are solid throughout and air-tight, I employ
a cover having in the centre an opening for the reception of a cylinder
or other description of vessel, which vessel will be open at the upper

page_text: extremity and be furnished with a grating or with perforations at the
lower end to admit of the gases escaping from the sewers. This vessel
or case being charged with charcoal or other deodorizing substance will
be passed through the opening in the cover, and will occupy the upper
part of the man-hole, and for protection from wet and dirt will be
covered by a cap that can be removed at pleasure for the purpose of
renewing the contents of the deodorizing case.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Arthur Jacob in the Great Seal Patent Office on
the 19th August 1869.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ARTHUR
JACOB, Civil Engineer, of Bromley, in Kent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twentieth day of February, in the year of our
Lord One thousand eight hundred and sixty-nine, in the thirty-second year
of Her reign, did, for Herself, Her heirs and successors, give and grant
unto me, the said Arthur Jacob, Her special licence that I, the said Arthur
Jacob, my executors, administrators, and assigns, or such others as I, the
said Arthur Jacob, my executors, administrators and assigns should at any
time agree with, and no others, from time to time and at all times there.
after during the term therein expressed, should and lawfully might make,
use, excrcise, and vend within the United Kingdom of Great Britain and
Ireland, the Channel Islands, and Isle of Man, an Invention for
"IMPROVMENTS IN THE VENTILATION OF SEWERS," upon the condition (amongst
others) that I, the said Arthur Jacob, 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 Arthur Jacob, 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 :-

page_text: My Invention has for its object improvements in the ventilation of
sewers, which I carry into effect by purifying the effluvia in their
escape to the surface of the ground, and by facilitating the disposal and
removal of charcoal or other material having the property of destroying
the injurious effects of sewer gases on health.
I carry out my object by means of man-hole covers, such as are
illustrated by the accompanying. Drawings.
As a cover to the man-holes used for the inspection of sewers and
drains I use castings similar to. Figs. 1 and 2 on the accompanying
Drawings, Fig. 1 representing a vertical section through the centre of
the apparatus, and Fig. 2 a plan of the same apparatus, one half of the.
inner casting called the "cap" being shewn as.removed..
The apparatus is composed of an outer frame marked F, which is
bedded on the top of the brickwork or masonry of the man-hole, and.
through which the descent is made into the sewers. Inside the frame,.
which is made slightly conical for its reception, is placed. the "cover,"
which is a cellular casting filled in either with blocks of wood or with,
other material, the centre portion of the cover being left open to receive
a cylinder of wrought iron. C and a cap, as illustrated. at Fig. 3.. In the
centre of the "cover" there is a circular opening surrounded by a
flange, upon which the cylinder is suspended by means of a collar that
is rivetted to it, and in this cylinder is placed charcoal or other
deodorizing: material.. The form of the receptacle for the deodorizing
agent may be varied at pleasure; it may be either a simple cylinder quite
open at the upper end and furnished with a grating at the lower end;.
or it may consist of two perforated cylinders, one fixed within the other,
as shewn at Fig. 4, both cylinders being closed at the bottom, and the
deodorizing agent being placed between the inner and the outer
cylinders. When the cylinder is filled with the deodorizing material and
placed in position, that is, in the centre opening, and resting upon a
ring of india-rubber or other elastic material to prevent the escape of
unpurified air between the casting and cylinder, the "cap" is then
dropped into the rectangular space in the centre of the cover and
effectually protects the contents of the cylinder from wet or road grit.
The cap used with the man-hole cover is slightly hollowed on two sides
so as to prevent the grit from stopping up the openings intended for the

page_text: escape of the purified air, and to furnish a hold by means of which the
cap can be easily removed.
The lamp-hole or ventilation shaft cover is precisely similar in the
principle of its action to the man-hole cover above described. It consists
of two castings, as illustrated by Figs. 5 and 6, which respectively
shew the apparatus in vertical section and in plan; Fig. 7 shews the
cap used with the lamp-hole cover. The outer casting consists of a
rectangular box marked B, having a flange, which is bedded on the
brickwork or masonry of the ventilating shaft or inspection shaft. The
centre of this casting is perforated with a circular opening similar in
every respect to that in the man-hole cover, and made to receive one or
other of the cylinders above described. Above the cylinders, when in
position, is placed the cap, Fig. 7, which is hollowed out at all the four
vertical sides to prevent the grit from the road clogging the openings.
In both the man-hole and lamp-hole covers there is at each corner of
the inner box a small passage made in the casting, and shewn in
section at Fig. 8, to admit of the escape of any water that may fall
through the openings. These outlets being carried down to nearly the
bottom of the casting become sealed when even a small quantity water
is introduced, whilst they effectually prevent the rain water from rising
sufficiently bigh to flow into the cylinder.
passes
The object of the apparatus is the purification of foul air as it
out up the sewers, which is effected as follows:-If the single cylinder
is used it is filled with charcoal, carbolate of lime, or other suitable
material broken into pieces one inch in diameter, and the sewer gases
passing through the cylinder and over the deodorizing material escape
from underneath the cup into the outer air perfectly purified. When the
double perforated cylinder is used the deodorizing material is broken to
a smaller size and placed between the inner and outer cylinder, and the
cases passing through the perforations and over the deodorizing agent
escape through the inner cylinder and so into the air.
Having now described the nature of my Invention, and the best means
that I am acquainted with for carrying out the same into operation, I
would have it understood that I do not confine myself to the exact
details herein shewn and described, which may be varied without
departing from the nature of my Invention, which consists in an

page_text: improved apparatus by means of which the deodorizing material
suitable for the purification of effluvia may be conveniently and cheaply
applied and renewed.
In witness whereof, I, the said Arthur Jacob, have hereunto set
my hand and seal, this Nineteenth day of August, in the year of
our Lord One thousand eight hundred and sixty-nine.
ARTHUR JACOB. (L.S.)