CERTAIN IMPROVEMENTS IN THE CONSTRUCTION OF FILTERS FOR THE PURIFICATION OF WATER AND OTHER LIQUIDS
Year: 1875

page_text: LETTERS PATENT to Henry Rawlings, of 162, Stamford Street, in the
Borough of Lambeth, for the Invention of "CERTAIN IMPROVEMENTS
IN THE CONSTRUCTION OF FILTERS FOR THE PURIFICATION OF WATER AND OTHER
LIQUIDS."
Sealed the 21st August 1875, and dated the 23rd March 1875.
PROVISIONAL SPECIFICATION left by the said Henry Rawlings at
the Office of the Commissioners of Patents, with his Petition, on
the 23rd March 1875.
I, HENRY RAWLINGS, of 162, Stamford Street, in the Borough of
Lambeth, do hereby declare the nature of the said Invention for
"CERTAIN IMPROVEMENTS IN THE CONSTRUCTION OF FILTERS FOR THE PURIFICATION
OF WATER AND OTHER LIQUIDS," to be as follows:—
Having found that the capillary currents of water and other liquids
passing through filtering materials or substances in the process of purifi-
cation have a tendency to pass in the shortest or most direct possible
distance or way, and only partially to pass in the more circuitous way,
and which defect is apparent in filtering vessels of all kinds.

page_text: The nature of my Invention is to direct or regulate the capillary
currents of liquids passing through filtering materials, that no one part
of that material may be more or less used than another part, and so
effecting the most economical use of the filtering material or substance.
To the ingress to and the egress from or either of them (the filter vessels)
I apply plates, discs, or diaphragms to retard the passage, and to dis-
tribute the volume of liquid at the seat of the greatest pressure, to also
regulate the comparative sizes, disposition, and distribution of per-
forations, and pipes to facilitate the distribution of the unfiltered to and
the gathering of the filtered liquid from those portions of the filtering
vessel most remote from the strongest draught, and provide a means for
regulating the total amount of water or other liquid passing through in a
given time, or entirely stopping it by a stop-cock or valve with a screw
working in the water channel to lessen the flow through if required.
Another part of my Invention consists in constructing portable and
household filters (by which term I mean filters not intended to be
placed in cisterns or used for manufacturing purposes, for which the
formerly described filters are best adapted), in such a manner that so
large an amount of filtering material or substance may be used, that
storage of purified water may be unnecessary, but that it may flow
directly through the filtering material to the tap in sufficient quantities.
The filter vessel is so constructed that the receptacle for the filtering
material or substance and the water holding space forms one vessel with
compartments, and a ready means is provided for cleaning or renewing
the filtering substance or materials by an aperture at a convenient part
of the receptacle for the filtering material, and which is provided with
an air-tight cover that may be removed at pleasure, and the material
cleaned or renewed. The flow of the water therefrom is regulated by a
screw which lessens or increases the aperture in the valve of the tap.
I also claim to use either application singly, or any convenient
combination of them, as may be desirable.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Henry Rawlings in the Great Seal Patent Office on
the 18th September 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY
RAWLINGS, of 108, Saint Martin's Lane, Charing Cross, in the Borough
of Westminster, and late of 162, Stamford Street, in the Borough of
Lambeth, Filter Manufacturer, send grecting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-third day of March, in the year
of our Lord One thousand eight hundred and seventy-five, in the thirty-
eighth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said Henry Rawlings, Her special licence, that
I, the said Henry Rawlings, my executors, administrators, and assigns,
or such others as I, the said Henry Rawlings, my executors, admini-
strators, 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 "CERTAIN IMPROVEMENTS IN THE
CONSTRUCTION OF FILTERS FOR THE PURIFICATION OF WATER AND OTHER LIQUIDS,"
upon the condition (amongst others) that I, the said Henry Rawlings, 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 Henry Rawlings, 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 and accompanying Drawings, that is to say :—
Having found in the course of a considerable experience in the
purification of water that the capillary currents of fluids passing through
filtering materials or substances in the process of purification have a
tendency to pass in the shortest or most direct possible distance or way,
and only partially to pass in the more circuitous way, and this defect is
apparent in filtering vessels of all kinds.

page_text: One part of my Invention is so to direct or regulate the capillary
currents of liquids passing through filtering materials that no one part
of that material may be more or less used than another part, and so
effecting the most economical use of and obtaining the best results from
the filtering material or substance. This defect being particularly
noticeable in cistern and other filters where the necessities of the case
require and will only admit of the use of very shallow filtering vessels,
I construct a vessel in any convenient material or shape, though I have
illustrated a rectangular one on Sheet (2); Figure (1) shows the end
view; Figure 2 (a longitudinal section) shows the general disposition
of the various arrangements.
A, A, A, are chambers which are entirely filled with the filtering
material by the openings (g, g, g,). B is the part of the filter from which
the water is drawn off, and the natural tendency is for the water to be
drawn to that point in the shortest possible distance, which would be
for the largest portion of its contents in diagonal lines more or less acute,
and the disuse to a considerable degree of that part of the material above
such lines. To remedy this defect I divide the space by plates or
divisions, which may be longitudinal and transverse or either of them,
also regulate the dispositions of gathering pipes and their perforations,
as shown at Figure (4), that there may be an equable draught, suction,
or pressure at all parts of the filter, and that each compartment or space
should yield an equal proportion of filtered water or other liquid.
In view of the varying qualities of water (as a greatly contaminated
water cannot be filtered so fast as one less so), I have provided a
regulating valve or tap (illustrated at B, Figure (2) and a full sized
section at Figure (5), which will give a perfect command over the gross
speed of filteration, and also allow of its use as a stop-cock. The per-
forations in gathering pipes should also be smallest near the end at (B),
which is the seat of the greatest draught, suction, or pressure, and
largest at the opposite extremities, and placed as far as possible from the
inlet of unfiltered water, as shown at (0), Figures (2 and 5).
Where there is no necessity for using such flat or shallow vessels as
filtering apparatus the same result is attained in a more simple way, as
shown on Sheet (1), Figure (4), where (A) is the chamber to be entirely
filled with the filtering material or substance; (C) is a plate or disc
perforated with fine holes to intercept or mitigate the direct draught,

page_text: suction, or pressure, and (D) the strainer for preventing the filtering
material from passing, and also perforated in a manner to prevent or
mitigate the direct draught, suction, or pressure.
The water or other liquid enters by perforations (a, a, a,) Figure 4, rises
through the filtering material in chamber (A) to the strainer (D) and is
drawn off at the union (c). The natural action is for the water or other
liquid to pass in the shortest and most direct course or way, which is the
centre of the filtering vessel, and to draw the liquid from the outside
holes in the bottom in capillary lines more or less acute. To regulate
this tendency I perforate the bottom of filtering vessels with holes
graduated in size, namely, smaller in the centre and larger towards the
edge or outside, and also provide an intercepting plate or disc perforated
with fine holes (and which plate or disc may extend entirely across and
entirely divide the filtering vessel, and be perforated with graduated
holes like the bottom of the filter if found requisite or desirable), and
the top strainer to be perforated on the upper part only. By this means
I regulate the draught, suction, or pressure, that it is made equable at
all parts of the filtering vessel.
To regulate the gross amount of liquid passing through the filter
I attach a fitting to the top, which is shown at (B), Figure 4, and also in
enlarged section. The screw (/) works in the waterway (k) and may by
screwing down upon the seating (1) be used as a stop-cock if required, or
may be adjusted to any desirable position to regulate or retard the flow
through the waterway.
The same dispositions or arrangements may and can be applied to main
service filters, and which I claim to include in this Patent.
Another part of my Invention consists in constructing portable and
household filters (by which term I mean filters not intended to be placed
in cisterns, or on the main service supply, or to be used for manu-
facturing purposes, for which the before described filters are best
adapted), in such a manner that so large an amount of filtering material
or substance may be used that the storage of filtered water or other
liquid is unnecessary, but that it may flow direct through the filtering
material to the tap, in a sufficiently large stream not to be inconvenient
in the using. This filter is shown on Sheet (1), Figure (3). The water or
other liquid to be filtered is put into the space marked (A.), enters the
chamber (B) containing the filtering material at the holes (a, a,); then

page_text: passes upwards to the strainer (6) and is carried off by the pipe (c, c,) to
the tap (d), without any intermediate storage or accumulation of the
water or other liquid.
A means of flushing or cleaning out the unfiltered water chamber is
provided by a hole at (g), which may be stopped by a cork or other con-
venient substance. The chamber (B) is filled by the removal of the water-
tight cap (f) in the centre of which is a hole, which provides for flushing
out the filtering chamber in case of an accumulation of dirt or other
clogging matter in it. The chamber (B) and the pipe (c, c,) being made
of pottery or any other convenient substance are practically in one piece,
and obviate the tendency to leakages and accident, which the use of
metal pipes and the necessary unions would lead to.
A means of regulating the flow of liquids through the tap is shown by
a section of the tap of Figure (3), where a screw is introduced in the
plug of the tap lessening or increasing the orifice or waterway to any
desired extent, and according to the degree of impurity of the liquids
under treatment.
When from the small size of the filter or other cause a storage of the
filtered liquid is necessary, either of the arrangements illustrated on
Sheet (1), Figures (1 and 2), are very efficient, without the necessity.
of using metal pipes or corks from which such frequent and unsuspected
leakages occur. (A) is the chamber for the unfiltered liquid; (B), the
chamber or receptacle (cylindrical in Figure (1), and semi-cylindrical in
Figure (2), for the filtering material; (C), the chamber or space for
the filtered liquid. The liquid enters at perforations (a, a), ascends
through the filtering material in (B) through the strainer (b) into the
pipe (c), and is then discharged through the orifice (d), (which is con-
tracted to the proper size by a mouthpiece formed of glass, pottery, or
other suitable material) to the receptacle (C), from which it is drawn off
by an ordinary tap. The chamber (B) for the filtering material is filled
or emptied by the openings (f), which are closed by earthenware or
other suitable appliance.
All these filters Sheet (1), Figures (1, 2, and 3;) are made entirely in
potteryware including the conducting pipes for filtered liquid, but I
claim nevertheless the right of applying this Invention to any other a
substance that may be found requisite, and although all the filters
illustrated are on the upward or ascending principle, I claim the right of
applying these improvements or any of them to descending filters also.

page_text: The filtering or purifying substance I prefer is animal charcoal, but
claim the right to use any other substance.
The following points constitute my claims in this Invention,-
1. To control and regulate the currents of any liquid in the process of
filteration or purifycation, by the arrangements shown and illustrated on
Sheet (2) or any modification of it, and similarly to control and regulate
the currents of any liquid in the process of filteration or purification by
the arrangement shown on Sheet (1), Figure 4.
2. To construct household and portable filters according to the
arrangements on Sheet (1), Figures 1, 2, 3.
3. I claim the use of either of the before described improvements
singly, or any desirable combination of them, and the right of varying
the sizes, shapes, and proportions to suit circumstances.
4. To construct filtering vessels the delivery pipes of which shall form
part of such vessels (some forms of which are illustrated on Sheet (1),
Figures (1, 2, 3), and Shect (2), Figures 2, 4, 5), and are preferably
constructed of pottery, or earthenware, or glass, but any other suitable
substance may be used.
In witness whereof, I, the said Henry Rawlings, have hereunto set
my hand and seal, this Seventeenth day of September, in tho
year of our Lord One thousand eight hundred and seventy-five.
גגTTT'
HENRY RAWLINGS. (L.S.)