IMPROVEMENTS IN FILTERING APPARATUS
Year: 1885

page_text: I, WILLIAM ROBERT LAKE, of the firm of Haseltine, Lake & Co Patent Agents
Southampton Buildings, in the County of Middlesex do hereby declare the nature
of my invention for "IMPROVEMENTS IN FILTERING APPARATUS" and in what
manner the same is to be performed, to be particularly described and ascertained in
and by the following statement:-
This invention relates to filters, and consists (1st) in a novel apparatus and.
method whereby. a proper quantity of a material for coagulating the impurities, or
for precipitating any excess of the coagulant, may be given to the water during the
passage from the source of supply to the filter bed, and (2nd) in an apparatus of
novel construction having an upper and lower compartment provided with suitable
inlet and discharge pipes, and connected by a transfer washer pipe or transfer
washer pipes extending through the partition or diaphragm separating the said
compartments; said pipe or pipes being utilized for conveying the filtering
material with water from the lower to the upper compartment, for the purpose
of cleansing it, after which the said filtering material is permitted to return
through a central valve to the lower compartment and the filtering proceeded with
as before.
The novel features of the second part of my invention pertain particularly to
certain improvements in the construction and arrangement of the transfer washer
pipe connecting the two compartments of the filter, in the valve through which the
filtering material is allowed to pass from the upper into the lower compartment,
and in certain formations of the base of the filter which facilitate the operation of
the apparatus and render it durable and effective.
In practising the first part of the invention may introduce into the water
contemporaneously with its passage into the filter, a substance which will produce
coagulation, or first a substance which will produce coagulation and then a sub-
stance which will operate to precipitate any excess of the coagulant, or introduce
simultaneously both a coagulant and a precipitant.
In the accompanying drawings.
Figure 1 is an exterior elevation of a filter and supply pipe embodying both
parts of my invention.*

page_text: Figure 2 is a central vertical longitudinal section of apparatus embodying the
first part of the invention shown in connection with a pipe leading to a filtering
apparatus.
Figure 3 is a side view of same.
Figure 4 is a top view of the receptacle shown in Figures 1 and 2.
Figures 5 and 6 are sectional views of certain modified forms of apparatus
constructed according to the first part of the invention and
Figure 7 is a view of a rod of coagulant, partly. in section, for use in the
receptacle shown in Figure 2.
Figure 8 is a central vertical section of a receptacle suspended below the supply
pipe.
Figure 9 is a top view of same.
Figure 10 is a transverse section on the line x x of Figure 8.
Figure 11 is a detached vertical section of the upper end of a pipe and of the
valve for regulating the flow of the water into it.
Figure 12 is a sectional view of a cap.
Figure 13 is an elevation of a modified form of receptacle suspended below the
supply pipe of the filter.
Figure 14 is a top view, and
Figure 15 a vertical section of same drawn to an enlarged scale.
Figure 16 is a central vertical longitudinal section of an apparatus embodying
the elements of the second part of my invention.
Figure 17 is a detached section of a portion of the filter shown in Figure 10,
illustrating the tie rods connecting the two heads of the filter.
Figure 18 is a transverse section of the apparatus in Figure 16 taken on the
dotted line ab and looking downward.
$
Figure 19 is a similar view of the same on the dotted line c d.
Figure 20 is a view, drawn to an enlarged scale, on the line of of Figure 16.
Figure 21 is a transverse section on the line g h of Figure 16.
Figure 22 is an interior view looking at the bottom of a filter of large size
constructed according to the second part of my invention.
Figure 23 is a plan view drawn to an enlarged scale of one of the funnel-shaped
outlets of the filter shown in Figure 22 and
Figure 24 is a central vertical longitudinal section on the line i j of Figure 23.
I will describe the first part of my invention shown in Figures 1 to 15 inclusive,
and then the second part thereof illustrated in Figures 16 to 24 inclusive, at the
same time indicating their joint operation.
Referring to the first part of the invention, A in Figures 1 to 15 of the drawings,
denotes the filter, and B a pipe leading thereto for supplying the water. At a
suitable point in the pipe B is applied the valve casing C, enclosing the valve D
which may be caused to impinge or recede from the seat E by the operation of the
threaded stem F. Above the valve E there is formed in the casing a gate G, over
which is placed a grating H and which leads to the receptacle K located over the
valve casing and having upon its upper end a cap M of any suitable construction.
The purpose of the receptacle K is to receive and protect a rod of solidified
coagulating material I, the lower end of which will rest upon the grating H and be
exposed to the action of the stream of water flowing through the pipe B, whereby.
a, sufficient quantity of the material is taken up by the water to coagulate the
impurities therein and facilitate their arrest by the filter bed.
=
The coagulating material in the rod I, may be of any suitable nature; I have
used among other substances, with good results, a rod composed of about ten parts
of alum to about one part of resin mechanically combinad. In the preparation.
of the rod, the resin and alum are melted and thoroughly mixed together, and
then poured into a cylinder L of paper or other suitable material and allowed to
cool therein, the upper end of the cylinder only being open. After the rod of
•

page_text: coagulating material has become hardened it is inserted into the receptacle K
through the open end of the cylinder, and the exposed end of the rod of material is
allowed to rest upon the grating H. In the absence of the resin or equivalent
agent the alum would be liable to break or crack and to too rapidly dissolve for
the purposes of the invention, but when the alum and resin are combined, the
latter not being soluble in water, binds the particles of the alum, and thus retains
the form and condition of the rod as well as preventing its rapid dissolution.
Other materials may be substituted for the resin (such for instance as mineral
pitch) if desired, and the alum may be discarded and other coagulating materials
used instead thereof according to the character of the water and the wish of the
manufacturer.
The alum or other coagulant may also be used in lump form, without the resin,
in filtering water to be used for certain purposes; and the coagulating material
may be compacted in the receptacle K without previous formation into a rod.
A coagulating material which I may employ instead of alum as aforesaid, is a
compound consisting of alum and perchloride or persulphate of iron. In preparing
this material, I prefer to use say, five pounds of alum to about one pound of
perchloride or persulphate of iron; the two are melted together and poured into a
mould of the desired form; after removal therefrom when cooled, the product is
coated with paraffine or some other waterproof varnish, especially at its sides, so
as to prevent a too rapid consumption of the coagulant by the action of the water.
The proportion of alum and perchloride of iron will vary, according to the
condition of the water and the character of its impurities; the proportions
mentioned, however, will be found entirely satisfactory in waters containing a
large amount of foreign matter.
It will be found entirely convenient and practical, however, in most cases, to
make use of a solidified rod of the coagulant, protected, except as to the lower end,
as herein before described.
.
The purpose of the cylinder L is to protect all parts of the rod of coagulating
material, except its lower end, from being acted upon by the water, and hence if'
paper is employed for the cylinder, it should be coated with varnish or paraffine to
prevent its, disintegration by the water. If desired, the cylinder L may consist
merely of a protecting coating of suitable material applied directly upon the rod of
material I. If the water were allowed to flow freely over all parts of the rod I,
the quantity of coagulant taken up thereby could only with difficulty be properly
regulated, and the results of the filtering process would be more or less uncertain
and unsatisfactory. It is desirable in all cases that only the quantity of the
coagulant find its way into the pipe B which will sufficiently coagulate the
impurities in the water to prevent their passage through the filter bed, for
otherwise either the impurities will not be arrested, or the excess of coagulating
material will prove objectionable. The quantity of the coagulant allowed to be
taken up by the water depends upon the character of the impurities contained
therein and other circumstances, and in the present instance I regulate it by means
of the valve D, which is moved near the seat E when a small quantity of coagulant
is to be given to the water, and farther from said seat when an increased quantity
thereof is to be taken up by the water; when the valve D is near its seat E a
reduced amount of the water is permitted to come in contact with the coagulant,
and when said valve.is removed farther therefrom a larger quantity of the water
acts upon the coagulating material and receives an increased amount of the same.
When the valve D is in the position shown in Figure 2, the full volume of water
passing through the supply pipe B will act upon the coagulant in the receptacle K,
and at this time the maximum quantity of the coagulant will be taken up by the
water; but when the valve has been moved say, to a point about on a line with
the longitudinal centre of the supply pipe, the volume of water will be divided
(without being diminished in quantity), one portion passing above and the
remainder below the valve, whereby but a limited quantity of the water will be

page_text: permitted to act upon the coagulant and a correspondingly reduced proportion of
the latter will be carried into the filter. In filtering water in which the impurities
may be arrested without great difficulty the valve D is moved near the seat E for
it is obvious that a small portion only of the coagulant is required, but when water
of a different character is being treated the valve is caused to recede further from
its seat. The valve D is a convenient and effective regulating device, but it is not
to be understood that I confine my invention to its employment or to any special
construction for dividing the current of water.
It should be observed that the coagulant does not protrude into the supply pipe
but is wholly within the receptacle K and is not exposed to the strong action of
the current of inflowing water. The manner of permitting the water to act upon
the coagulant in the art to which this invention relates is important, since if the
water should become overcharged therewith the result would prove unsatisfactory.
According to my invention the coagulant is only exposed to the action of the water
at the point where the receptacle K opens into the supply pipe and even at this
point the coagulant is removed from the direct force of the current.
The rod of material I is gradually washed away by the flowing water and
requires to be replenished from time to time as occasion may require. The specific
gravity of the rod serves to retain it in contact with the grating H, and the degree
of its dissolution may be indicated by a rod N which will follow the upper surface
of the coagulating material in its descent,
When it is desired to insert a fresh rod of material in the receptacle K, the
valve D is closed without checking the flow of water to 'the filter and the cap on
the upper end of the receptacle opened, when another rod may be introduced.
I do not limit the use of the apparatus hereinbefore described to supplying any
special coagulating material to the water, nor to the supplying of a coagulant, since
in the practice of the processes hereinbefore described the coagulant may be
introduced into the pipe B elsewhere, and a material for precipitating any excess
of the coagulant placed in the receptacle K; for instance sulphate of iron for
coagulating may be introduced into the pipe B at any convenient point and lime
as a precipitant placed in the receptacle K. Or the receptacle may contain both
a coagulant and precipitant, such as iron and lime. Nor do I limit myself to the
employment of any certain number of the receptacles K.
The receptacles K illustrated in Figures 5 and 6 are filled with coagulating
material in lump form. In the form shown in Figure 6 the material is protected
from direct contact with the flowing water by reason of the peculiar construction
of the valve D and in that shown in Figure 5, owing to the fact that the receptacle
is connected with the pipe B by a smaller intermediate pipe x containing a valve y
In the employment of the receptacles K illustrated in Figures 5 and 6 a small
quantity of water constantly remains around the coagulating material and becomes
thoroughly charged therewith and will be taken up by the water passing through
the pipe B on its way to the filter. The water gathered in the receptacle operates
to transfuse the coagulant into the main body of the water, while at the same time
the material is not subjected to the direct action of the current. The valve D
having a stem w adapted to move in the sleeve u shown in Figure 6, permits the
pressure in the pipe B to keep the coagulating material constantly surrounded with
water, and the transfusion of the charged portion of the water into the main body
to be filtered.
I have herein before described the receptacle K containing a solid coagulant
arranged over the supply pipe leading to the filter, but it must not be understood
that the invention is limited to this arrangement of the receptacle K, since it may
be desired under certain conditions to use the coagulant in solution, and when it
is thus used the receptacle K will be arranged below the supply pipe B, the
receptacle being supported upon a suitable standard or made a section of the
pipe B. In Figures 8 to 12 inclusive, I illustrate a view of the receptacle K when
made a part of the supply pipe B and adapted to contain the coagulant or the

page_text: 5
precipitant in liquid form. In said figures the receptacle K illustrated is formed
of cast iron and is supplied with a cap or cover having a removable screw plug
indicated by the numeral 4, by means of which plug the coagulant may be
introduced into the receptacle. In the upper part of the receptacle is cast a curved
passage 5, the ends of which are connected with the supply pipe B, as indicated
in Figures 8 and 10. The passage 5 is curved in order to retard or create a
greater resistance to the flow of the water than would a mere straight channel
across the receptacle, the purpose being to cause a definite proportion of the water
to descend through the pendent pipe 6, extending downward from the passage
into the receptacle K, and to ascend through the adjacent similarly constructed
and arranged pipe 7, thence again entering and mixing with the water as it is
carried toward the filter and affecting it the same as the solid coagulant contained
in the receptacles illustrated in Figures 1 to 7 of the drawings. In the head of
the receptacle K illustrated in Figures 8 to 12 are arranged valves 9 operated by
hand wheels 10 and having seats upon the upper ends of the pipes 6, 7, the purpose.
of the valves being to open the inlet to the pipe 6 and the outlet from the pipe 7
more or less according to the condition of the water and the quantity of the
coagulant it is desired to give to the same. The particular construction of the
valves 9 is illustrated in Figure 11.
In the operation of the apparatus illustrated in Figures 8 to 12 inclusive, the
coagulant in solution is placed within the receptacle, and the valves 9 adjusted
according, as aforesaid, to the quantity of coagulant necessary to affect the proper
result. The water flowing through the pipe B from the source of supply to the
filter passes through the passage 5, and its free flow being there impeded, a
portion of the water, in a continuous current, will pass downward through the
pipe 6, become charged with the coagulant and ascend through the pipe 7, com-
bining again with, and being carried by, the main volume of water passing to the.
filter. The return of the water upward through the pipe 7 is caused by the..
continued pressure of fresh water entering the receptacle through the pipe 6. The
volume of the stream of water entering the pipe 6 is in a large measure governed
by the valves 9 and the size of the pipe, but the rapidity of the flow is mainly
controlled by the resistance offered to the water by the peculiar formation and
arrangement of the passage 5. In order to increase the resistance to the flow of
the water in the passage 5, the said passage may, if desired, be irregularly curved or
provided with projections and grooves on opposite sides and arranged alternately
with relation to each other, thus increasing the flow of water downward through
the pipe 6. The peculiar formation of the passage 5, operates as a valve between
the pipes 6, 7, increasing the pressure of the water on the pipe 6, and corre-
spondingly reducing it at the upper end of. pipe 7, thus ensuring a proper
passage of the water downward through said pipe 6. and upward through the
pipe 7 in exactly the proportion and force desired. In lieu of the passage 5, I may
if desired introduce a valve 11 into the supply pipe (see Figure 13) and suspend
the receptacle K from said supply pipe by the pipes 6, 7, extending, above the
receptacle and entering the supply pipe B. The pipes 6 and 7 between said
receptacle and said pipe are provided with valves 9, as indicated in Figures 13
and 14, wherein I illustrate the receptacle supported upon a standard 12.
The operation of the receptacle K in Figure 13 is exactly similar to that of the
apparatus illustrated in Figure 8. By moving the valve 11 into or withdrawing
it from the pipe B the pressure of the water at the upper end of pipe 6 may be
regulated at will. In figure 14 I illustrate a top view of the receptacle shown in
Figure 13, and in Figure 15 is shown an enlarged central vertical section of same.
Referring to the second part of my invention shown in Figures 16 to 24
inclusive, A in said Figures designates the filter divided by a central diaphragm
or partition B into two compartments lettered C, D, respectively, the latter
containing a bed of granular filtering material E, and the former being of suitable
size to receive the same during the washing process hereinafter described.

page_text: The compartments CD of the filter are connected by a central transfer washer
pipe F passing from a point adjacent to the base of the lower compartment D to
the upper portion of the compartment C, its upper end being provided with a
suitable valve G of well known construction. The centre of the diaphragm B11
contains a circular opening provided with a valve seat H having downwardly
converging sides I as shewn in Figure 16, and the centre of this opening forms a
suitable space through which the transfer pipe F passes.
That portion of the washer pipe F within the upper compartment C is enclosed
by a vertically adjustable pipe or cylinder J externally threaded upon its upper
end, and having upon its lower end a horizontal flange K between the lower surface
of which and the upper surface of the plate L is arranged a disc of india-rubber M,
the latter being held in place by bolts N passing through the said plate L and
flange K. The disc or valve M is of suitable size and outline to enter and impinge
against the converging walls of the valve seat M. The upper threaded end of the
tube or cylinder J engages the internal thread of the screw Q which is supplied
with a hand wheel P and is enclosed between the collars O on the transfer pipe F.
The pipe F is stationary and the tube J is adjustable vertically thereon by means
of the screw Q. By operating the screw in one direction it will cause the elevation
of the cylinder J and consequently raise the valve M from its seat H at which time
the sand or other granular filtering material in the compartment C may return
through the space between the said seat and the pipe F into the lower compart-
ment D. When the said screw is rotated in the opposite direction the cylinder J
will be lowered and the valve M will come in contact with its seat H and thus
close the openings between the two compartments of the filter.
The cylinder J is feathered on the pipe F as shown at R, in order that when the
screw is turned the said cylinder will have a direct vertical movement without
rotating. It will be observed that the india-rubber valve M may be compressed
more or less firmly against the converging walls of its seat H by the amount of
rotation of the screw Q and in this respect the valve constructed as described is of
great advantage, since a perfectly watertight joint may be formed even though
particles of sand may have been deposited on the sides of the valve seat. The
valve described is superior in that it will resist the abrasion of the sand passing
from the upper to the lower compartment of the filter and will not become worn
except through long continued use. The upper disc M, also, may be detached and
a new disc substituted without difficulty and at a trifling expense.
The diaphragm B¹¹¹ to the centre of which the valve seat H is secured, is of cast
iron, and is secured on tie-rods connecting the cast-iron head S of the filter with
the cast-iron base T, as illustrated in Figure 17, that portion of the filter between
the diaphragm and the head and base being of boiler iron.
In the base of the filter are the funnel shaped formations V, arranged as shewn
in Figure 18, to cover a large portion of the interior face of the lower head of the
filter. The funnel shaped formations V, illustrated in Figures 16 and 18, are cast
in the lower head T and connect with the passage W leading to the delivery pipe X,
by which the filtered water may be led from the apparatus. The openings at the
upper and lower ends of the funnels V are covered by perforated metal or wire
cloth Y, and the space between these two pieces of wire cloth or perforated metal
is about four-fifths filled with coarse shot or other suitable spherical bodies Z, or
material in the form of flakes or coarse granules, the purpose of which is to permit
the use of wire cloth of coarse mesh or coarsely perforated metal at the upper and
lower edges of the funnels V, at the same time preventing the escape of the sand or
other filtering media.
Where wire screens alone are employed to support a bed of filtering material
they must necessarily be of delicate texture, (otherwise the sand would escape with
the water) and hence they invariably, especially in large filters, become bent,,
broken, and clogged with impurities, and repairs are frequently required, resulting
in delays and expense. When, however, the spherical bodies Z are made use of,

page_text: coarse perforated metal or wire cloth may be employed, the spherical bodies serving
to prevent any sand which might pass through the upper piece of wire cloth from
escaping with the water. Upon the reversal of the current for the purpose of
cleaning the filter bed the spherical bodies will be loosened and permit any sand
and impurities held by them to repass upward through the wire cloth into the
filter, and thence upward through the transfer pipe F.
The water to be filtered passes into the compartment D through the supply
pipe B having a valve B¹, and the purified water escapes in the delivery pipe ✗,
before mentioned, having a valve C. The supply and delivery pipes B and X
respectively, are connected by a pipe D¹ supplied with a valve El, and from the
pipe X between the pipe D¹ and the filter, a pipe F' having a valve Cu passes into
the upper compartment of the filter. From the upper portion of the upper com-
partment C passes an escape pipe H for waste water and from the upper portion of
the compartment D passes also an escape pipe I¹ for waste water, the latter pipe
having a valve J' and leading into the waste pipe H above mentioned.
In the operation of the filter above described the bed of filtering material being
in the lower compartment and the valves J¹, G E' and. C" being closed and the
valves B and C¹ being open, the water to be purified is passed into the compart-
ment D through the pipe B, whence it percolates downward through the filtering
material E the impurities being arrested in transit and escaping into the various
funnel shaped formations V, thence passing downward through the shot or flakes Z⚫
and into the space W, from whence it is delivered through the pipe X into the
service pipes of the city or house. After the bed of filtering material has become
foul from the arrested silt and other impurities, it will be necessary to wash the
same and this is accomplished by closing the valve B and C and opening the
valve E and G under which condition of the apparatus the water will flow through
the pipes B, D¹, and into the space W in the base of the filter, thence upward
through the shot Z and perforated material or wire cloth Y into the lower portion
of the filter bed E the effect being that the filtering material will be thoroughly
agitated in all its parts and, the pressure of water continuing, the sand with the
water will flow upward through the transfer pipe F and be deposited in the upper
compartment C of the filter, the waste water being permitted to escape with the
impurities through the pipe H'. It is a matter of the utmost importance that the bed
of granular material E be thoroughly agitated throughout all its parts, especially
those parts contiguous to the sides of the lower portion of the filter, by the water
flowing upward through the entire wire cloth or perforated metal Y during the
washing process, since if this is not done, the sand will remain firm adjacent to the
walls of the filter and gradually taper downward in the form of an inverted cone
toward the lower end of the transfer pipe F and will in this condition after the.
filter has been in use for a time become hardened by the accumulation of impurities
and form an obstruction to, the successful use of the filter. In some instances
I have built an inverted cone shaped formation around the lower inner circum-
ference of the filter in order to direct the sand to the mouth of the transfer pipe F,
but I consider it necessary especially when it is desired to filter large quantities of
water to utilize every available space within the filter and to this end the said
inverted cone shaped formations have been discarded and the series of inlets V
supplied, whereby I am enabled to secure all of the space within the compartment D
for the filter bed, and at the same time prevent any portion of the latter from
becoming hardened or resisting the action of the water during the washing process.
When a series of inlets for admitting the water during the washing process is
employed, all of the sand in the compartment D will enter the washer pipe F and be
transferred to the upper compartment in the manner before described, no important'
portion of the same remaining in the lower compartment. After the sand has
been transferred into the upper compartment and it is desired to return the same
to the lower compartment the valves G and E are closed, and the valve M elevated
from its seat by means of the screw Q, at which time the sand will return through

page_text: In
the space at the centre of the diaphragm B₁₁₁ into the lower compartment, the
water in which, in the meantime being permitted to escape through the waste pipe
by opening the valve J¹. After the sand has re-entered the lower-compartment D
the valves M and J¹ are closed, and the valves B' and' C¹¹ opened, this condition
of the valves permitting the first water filtered through the bed E and which may
be more or less impure to ascend through the pipe F and enter the upper com-
partment of the filter where it may assist in washing the sand bed upon its being
again transferred to that compartment. After the compartment C has been again
about filled with the first water passed through the filter, the valve C will be
closed and the valve C¹ opened and the operation of filtering proceeded with as before.
In Figure 22 I have illustrated an arrangement of the funnel-shaped formations V
in a filter of large size, the said arrangement being taken from filters of my own
construction six and one half feet in diameter. In the filters of this size it might
be difficult or impracticable to cast the funnel-shaped formations V in the lower
head of the filter, and I have therefore cast them separately, and connected them
by means of the branch pipes M¹ with pipes N' leading to the delivery pipe X, as
shewn in said Figure 22. It will be found expedient in filters of this size to
distribute the parts V over the greater portion of the lower head of the filter, and to
employ four or more transfer washer pipes F, as well as to connect the heads of the
filter by a series of the rods 01 and to sustain the walls of the filter by braces R'.
I have introduced Figure 22 for the purpose of illustrating the general plan and
arrangements of the parts V in a large filter, but in Figures 23 and 24 I shew in
enlarged views the particular construction of a single one of said parts for the
purpose of more clearly disclosing the invention sought to be protected.
Figure 24, I have omitted the shot or other spherical bodies Z from the funnel-
shaped device V since these are shewn with sufficient accuracy in Figure 16. The
castings V shewn in Figures 22, 23, and 24 have an angular passage R11 leading
from the pipes M¹ to the lower surface of the perforated metal or wire cloth Y, as
illustrated by dotted lines in Figure 23 and in full lines in Figure 24.
passage R is curved adjacent to the wire cloth Y, and in this curved portion is
placed the metallic ball S¹. During the operation of filtering, the ball S¹ is driven
by the pressure of the water against a pin T¹, at which time the escaping water
will pass around and over the ball, the casing being concaved at V₁ to permit of
this operation. When the filter is at rest the normal position of the ball will be
at the lower point of the passage R¹¹ and upon the reversal of the current for the
purpose of washing the filter bed in the manner hereinbefore described, the water
will force the ball S¹ into the upper end of the passage R" and against the lower
surface of the wire cloth or perforated metal Y, at which time the ball will act as
a resistance to the water, restricting its flow into each opening V whereby all of
the pipes M¹ will be filled with water under pressure and each funnel-shaped
opening V will be required to perform its proper share of the work the purpose.
being to ensure the thorough agitation of the filtering material in all its parts.
The ball S¹ may be placed in the passage leading to the funnel-shaped openings V
in Figure 16, but for clearness of illustration I have omitted them from the said
figure and only shew the same in Figures 23 and 24. When the ball S' is in the
position illustrated in Figure 24 the water will pass around it in the angles of the
passage R, indicated more clearly in Figure 23 by dotted lines. It will not be
necessary to employ the ball valves S₁ in every instance since the pressure of water
will often be sufficient to fill all of the pipes M' and funnel-shaped openings V and
thoroughly agitate the filtering material.
The
The funnel-shaped openings V are of marked advantage in that the enlarged
upper portion thereof exposes a large surface of the sand to the action of the water
during the operation of washing the filter bed or from which to receive the water
while filtering.
In the foregoing description I have described the bodies Z as being spherical in
form, but it is to be understood that this term is to cover any small bodies, such

page_text: as granular structures, which will resist the escape of the filtering material without
unduly obstructing the flow of the water, and, as hereinbefore described, material
in the form of flakes may be substituted for the grànular or spherical bodies.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed as communicated to
me by my foreign correspondent I declare that what I claim is
First. In combination with a filter, a supply pipe for unfiltered water leading
thereto; a receptacle opening into the supply, and a coagulant, the latter being
held by the receptacle and exposed at the said opening to the action of the inflowing
water; substantially as set forth.
Second. In combination with a filter and a supply pipe for leading the water
thereto, a receptacle K connected with said pipe and containing a solidified
coagulating agent, and a valve, whereby the quantity of said agent taken up by the
flowing water may be regulated; substantially as set forth.
Third. A filter supply pipe in combination with the valve D arranged therein,
the receptacle K located over the valve, a gate leading into said receptacle, and an
open support H which will permit the water flowing through the supply pipe to
enter the receptacle; substantially as set forth.
Fourth. In combination with a filter supply pipe, a receptacle connected with the
said pipe and enclosing a substance to be acted upon by the flowing water, and a
valve whereby the quantity of the substance taken up by the water may be
regulated, substantially as set forth.
Fifth. In combination with a filter supply pipe, a regulating valve arranged in
said pipe, and a receptacle located adjacent to said valve and containing a substance
to be acted upon by the flowing water, substantially as set forth.
Sixth. In combination with a filter, a supply pipe leading thereto, a receptacle
forming a section of or connected with said pipe and containing a coagulant or
precipitant, a pipe leading from the supply pipe to said receptacle, and a return
pipe passing from the receptacle into the supply pipe; substantially as, and for the
purposes, set forth.
Seventh. In combination with a filter, a supply pipe leading thereto, a receptacle
forming a section of or connected with said pipe and containing a coagulant or
precipitant, a pipe leading from the supply pipe into said receptacle, a return pipe
passing from the receptacle into the supply pipe, and a valve or analogous,
structure located in the supply pipe between said smaller pipes entering the
receptacle; substantially as set forth.
Eighth. In combination with a filter, a supply pipe leading thereto, a receptacle
forming a section of or connected with said pipe and containing a coagulant or
precipitant, a pipe leading from the supply pipe into said receptacle and having a
valve, a return pipe supplied with a valve and passing from the receptacle into the
said supply pipe, and a valve or analogous structure located in the supply pipe
between said 'smaller pipes entering the receptacle, substantially as set forth.
Ninth. A filter consisting of compartments having suitable inlets and outlets for
water and connected by a transfer washer pipe, one of the compartments containing
a bed of filtering material and having at the base of the bed numerous inlets for
the water used in transferring the filtering material through the washer pipe into
the adjacent compartment; substantially as, and for the purpose, set forth.
Tenth. A filter consisting of compartments having suitable inlets and outlets,
for water and connected by a transfer washer pipe, one of the compartments
containing a bed of filtering material and having distributed over its base series
of funnel-shaped openings protected by perforated metal or wire cloth; substantially
as, and for the purpose, set forth.
Eleventh. A filter consisting of compartments having suitable inlets and outlets
for water and connected by a transfer washer pipe, one of the compartments
containing a bed of filtering material and having at the base of the bed a series of

page_text: openings protected above and below by perforated metal or wire cloth and enclosing
a quantity of spherical or granular material or material in the form of flakes;
substantially as set forth.
Twelftb. A filter consisting of compartments C, D connected by a transfer washer
pipe F, and having suitable inlets and outlets for water, the base of the compart-
ment D having openings V protected above and below by perforated metal or wire
cloth Y, and enclosing spherical or other suitable bodies Z and leading into a
passage W connected with the delivery pipe; substantially as set forth.
Thirteenth. A filter consisting of compartiments C, D separated by a diaphragm Bui
and having suitable inlets and outlets for water, combined with a transfer washer
pipe F passing from one compartment to the other, a valve seat at the centre of
said diaphragm, and a valve secured on the lower end of the cylinder J enclosing
the pipe F and adapted to be operated by a screw Q; substantially as set forth.
Fourteenth. A filter sub-divided by a diaphragm into compartments connected
by a transfer washer pipe, and having suitable inlets and outlets for water,
combined with à valve seat in the diaphragm encircling the washer pipe, a
corresponding elastic valve, the cylinder enclosing the upper portion of said pipe
and carrying said valve, and a hand wheel engaging a thread on the said cylinder
and collared on the upper end of the transfer pipe; substantially as, and for the
purpose, set forth.
Fifteenth. A filter consisting of compartments C, D, connected by a transfer
washer pipe F, the base of the lower compartment containing protected openings V,
in combination with the pipes B, D¹, X, F¹ H¹ provided with valves; substantially
as, and for the purpose, set forth.
Sixteenth. In combination with a filter containing a bed of filtering material,
the base having a series of funnel-shaped openings protected by perforated metal,
the passage W connecting said openings, and a delivery pipe leading from said
passage; substantially as, and for the purpose, set forth.
Seventeenth. A filter having suitable inlets and outlets for the water and
containing a bed of filtering material, combined with a base having a series of
funnel-shaped openings protected above and below by wire cloth and enclosing
quantities of spherical bodies, and a passage connecting said openings with a
delivery; substantially as set forth.
Eighteenth. A filter having inlets and outlets for the water, and enclosing a bed
of filtering material in granular form, in combination with a series of openings V
at the base of the filter protected by perforated metal and a ball valve S¹;
substantially as and for the purposes set forth.
HASELTINE, LAKE & Co.,
For the Applicant.