IMPROVE- MENTS IN THE MODE OF AND APPARATUS FOR PREPARING LIME FOR THE TREATMENT OF SEWAGE
Year: 1872

page_text: LETTERS PATENT to Henry Young Darracott Scott, of Ealing, in the
County of Middlesex, Major-General, C.B., and Thomas Walker
Scott, of the same Place, Gentleman, for the Invention of "IMPROVE-
MENTS IN THE MODE OF AND APPARATUS FOR PREPARING LIME FOR THE
TREATMENT OF SEWAGE."
Sealed the 3rd June 1873, and dated the 4th December 1872.
FROVISIONAL SPECIFICATION left by the said Henry Young Darracott
Scott and Thomas Walker Scott at the Office of the Commissioners
of Patents, with their Petition, on the 4th December 1872.
We, HENRY YOUNG DARRACOTT SCOTT, of Ealing, in the County of
Middlesex, Major-General, C.B., and THOMAS WALKER SCOTT, of the
same Place, Gentleman, do hereby declare the nature of the said In-
vention for "IMPROVEMENTS IN THE MODE OF AND APPARATUS FOR PREPARING
LIME FOR THE TREATMENT OF SEWAGE," to be as follows:-—
The main object of our Invention is to economize labour when
treating sewage with lime for the purposes of defecation and utilization.

page_text: In carrying out our Invention we employ tanks or vessels, such as are
ordinarily employed for making the milk of lime used in precipitating
sewage. This tank or vessel is to be filled with water or sewage water,
and is provided with a stirring apparatus consisting principally of a
vertical axle with horizontal or inclined arms, from which are suspended
metal baskets or perforated boxes with sliding bottoms containing the
lump lime, which will therefore be immersed in the water contained in
the tank. or vessel. As the vertical axle rotates it carries round the
boxes containing the lime, which will gradually slake and be washed
out by the water and will pass through the holes at the sides and bottom
of the boxes. The under burned and over burned lime and any
extraneous matter, such as stones or flints, will remain in the boxes, and
may be removed therefrom from time to time and cast on to a heap,
where they may be allowed to remain and heat, after which the lime;
when screened, may be again placed in the boxes and immersed in the
water, or thrown direct into the tanks. Horizontal or inclined arms are
mounted on the vertical axle below the boxes, and are furnished with
teeth, which project downwards, to stir up any sediment or lime at the
bottom of the tank.
It will be understood that water may be kept constantly running into
the mixing tank and a regulated quantity as constantly drawn off by a
pipe or valve suitably adapted to the vessel for the purpose, so that the
workmen will only have to keep the boxes supplied with lime and-sce
that the extraneous matters are removed therefrom from time to time.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Henry Young Darracott Scott and Thomas
Walker Scott in the Great Seal Patent Office on the 4th June 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, HENRY
YOUNG DARRACOTT SCOTT, of Ealing, in the County of Middlesex,
Major-General, C.B., and THOMAS WALKER SCOTT, of the same Place,
Gentlemen, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fourth day of December, in the year
of our Lord One thousand eight hundred and seventy-two, in the thirty-

page_text: sixth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto us, the said Henry Young Darracott Scott and
Thomas Walker Scott, Her special licence that we, the said Henry
Young Darracott Scott and Thomas Walker Scott, our executors,
administrators, and assigns, or such others as we, the said Henry
Young Darracott Scott and Thomas Walker Scott, our 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 THE MODE OF AND APPARATUS FOR PREPARING LIME FOR THE TREATMENT OF
SEWAGE," upon the condition (amongst others) that we, the said Henry
Young Darracott Scott and Thomas Walker Scott, our executors or
administrators, by an instrument in writing under our, 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 we, the said Henry Young Darracott Scott and
Thomas Walker Scott, do hereby declare the nature of our said
Invention, and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following state-
ment, reference being had to the Drawing hereunto annexed, and to the
letters and figures marked thereon (that is to say) :—
The main object of our Invention is to economise the labour which is
now required for first slaking and then screening the lime when treating:
sewage with lime, for the purposes of defecation and utilization. The
addition of lime to sewage, as now practised for the above purposes,
requires constant attention and depends upon the workman keeping up
a regular and uniform supply. A negligent performance of this duty
will either involve an imperfect defecation of the sewage, or a waste of
lime. In order to obviate these defects we arrange our apparatus so
that it shall work as nearly as possible automatically.
In carrying out our Invention we employ tanks or vessels such as
are ordinarily employed for making milk of lime and in precipitating

page_text: In the accompanying Drawing I have shewn a convenient arrangement
of apparatus for effecting the desired object. The tank or vessel a, a, may
be constructed of masonry, brickwork, concrete, or of iron, and is filled
with water or sewage water. It is provided with a stirring apparatus,
consisting principally of a vertical axle 6 with horizontal or inclined
arms c, c, from which are suspended perforated sheet metal or wire
baskets or boxes d, d, provided with sliding bottoms d', d¹. These boxes
or baskets contain the lump lime, which will therefore be immersed in
the water contained in the tank or vessel. As the vertical axle b rotates
it carries round the boxes d, d, containing the lime, which will gradually
slake and be washed out by the water and will pass through the holes at
the sides and bottom of the boxes. The under burned and over burned
lime and any extraneous matters, such as stones or flints, will remain in
the boxes, and may be removed therefrom from time to time and cast
into a heap, where they may be allowed to remain and heat. By this
means, the lime will be separated from the refuse mentioned above, after
which the lime so separated may, when screened, be again placed in the
boxes d, d, and immersed in the water or thrown direct into the tanks.
Horizontal or inclined arms e, e, are mounted on the vertical axle b
below the boxes d, and are furnished with teeth e¹, e¹, which project
downwards to stir up any sediment or lime at the bottom of the tank.
It will be understood that water may be kept constantly running into
the mixing tank and a regulated quantity of water having in solution
and suspension the finest particles of the lime may be as constantly drawn
off by a pipe or valve f, suitably adapted to the vessel for the purpose, so
that the workman will only have to keep the boxes d supplied with lime
and see that the extraneous matters are removed therefrom from time to
time. At or near the centre of the tank or vessel a are openings or
channels g, g, communicating with a common channel g¹, so that the
sediment and insoluble particles may be from time to time drawn off.
The boxes or baskets d, d, are provided with hooks d², whereby they are
suspended from the horizontal arms c, c, in such a manner that they may
be easily lifted off when required by means of a hook passed through the
eye d. The hooks ď² are also provided with antifriction rollers, so that
the boxes d may be easily slidden along the arms.
As an obvious modification of this arrangement it will be evident that
instead of suspending the boxes or baskets d, d, from the horizontal
arms c, c, as above described, they may be placed on a platform fixed

page_text: to the vertical shaft, and may be provided with small rollers or running
wheels for the facility of moving them about. In whatever way the
boxes or baskets are used they must be moved round in the water in the
tank by communicating rotary motion to the vertical shaft by means of
any suitable gearing.
Having now described our Invention of "Improvements in the Mode
of and Apparatus for Preparing Lime for the Treatment of Sewage,"
and having explained the manuer of carrying the same into effect, we
claim as the Invention secured to us by Letters Patent as aforesaid,
preparing lime for the treatment of sewage by placing unslaked lime in
perforated boxes or baskets, which are suspended in water and are moved
round or about therein, in order that the lime may be gradually dissolved
or washed out of the boxes or baskets, and the solution regularly drawn
off as and for the purpose herein set forth.
We also claim the arrangement of apparatus herein set forth, or any
mere modification thereof, whereby unslaked lime may be gradually
dissolved and diffused through a body of running water, as and for the
purpose herein set forth.
In witness whereof, we, the said Henry Young Darracott Scott and
Thomas Walker Scott, have hereunto set our hands and seals, the
Second day of June, in the year of our Lord One thousand eight
hundred and seventy-three.