IMPROVEMENTS IN FILTERING AND PURIFYING WATER AND OTHER LIQUIDS, AND IN THE APPA- PATUS EMPLOYED THEREIN
Year: 1876

page_text: LETTERS PATENT to Francis Thomas Bond, of Gloucester, in the County of
Gloucester, Doctor of Medicine, for the Invention of "IMPROVEMENTS IN
FILTERING AND PURIFYING WATER AND OTHER LIQUIDS, AND IN THE APPA-
PATUS EMPLOYED THEREIN."
Sealed the 30th September 1876, and dated the 5th July 1876.
PROVISIONAL SPECIFICATION left by the said Francis Thomas Bond at the
Office of the Commissioners of Patents on the 5th July 1876.
FRANCIS THOMAS BOND, of Gloucester, in the County of Gloucester, Doctor of
Medicine. "IMPROVEMENTS IN FILTERING AND PURIFYING WATER AND OTHER
LIQUIDS, AND IN THE APPARATUS EMPLOYED THEREIN."
The object of this Invention is three-fold,-
First. To construct a vessel which shall float upon the water or other liquid which
has to be filtered, and whilst so floating shall by syphon action through a tube
attached thereto filter the water or liquid in which it floats. For this purpose I
construct a vessel, preferably though not necessarily, of cylindrical shape, and con-
sisting of three cylinders of graduated size fixed one within the other in the
following way:- -The innermost cylinder is open at one end and closed at the other.
The
To the open end a cap is adapted so as to close it in a water-tight manner.
cylinder thus formed is fixed in a water-tight way (preferably by soldering if the
vessel be made of metal) in the bottom of a somewhat larger cylinder, the top of
which is open, and in such a manner that its open bottom end (to which the cap is
attached) is fixed in the closed bottom end of the second cylinder, and projects for a
short distance through it. The open top of the second cylinder is attached to the
inside of the closed top of a third cylinder (which is open at the other end) in such
a manner (by the latter cylinder being adapted to the former by means of a rim)
that the one can be separated from the other, or that they can be kept united in a
water-tight manner. The outermost cylinder, which when the vessel is standing in
its naturally vertical position is closed at the top and open below, does not extend
for more than two thirds of the way down over the second cylinder, and forms from
the way in which it is constructed an air chamber, by adapting the capacity of
which to the size and weight of the vessel, the latter can be buoyed up on the
surface of the liquid. A small tube enters the side of the innermost cylinder close

page_text: to the bottom, where the cap is attached, and this tube is prolonged in a vertical
direction for a short distance upon the outside of the second cylinder. By this tube
liquid enters the innermost cylinder whilst the vessel is floating. The innermost
cylinder communicates with the middle one by means of a small vertical tube, the
upper end of which is bent at right angles, so as to be applied to an aperture at the
top of the outer side of the inner cylinder, and the lower end terminates by means
of a free aperture close to the bottom of the middle cylinder, in which this tube
wholly lies.
The innermost cylinder may be divided into two parts by a horizontal perforated
partition, so that three separate kinds of filtering materials can be introduced into
the vessel, viz., two in the innermost cylinder and one in the middle cylinder, in
which case the upper end of the innermost cylinder should be open, and have a
water-tight fitting cap applied to it; or an additional cylinder may be interposed
between the middle one and that which acts as the air chamber, in which case it is
necessary to connect the innermost and middle cylinders by an aperture through
the partition which separates the two at its upper end, and the middle and outer
cylinders by a similar aperture in the partition which separates the two at the
bottom.
Into the centre of the plate which serves as the common top of the middle and
outer cylinders a small tube is fixed, one end being in the middle cylinder and the
other outside the vessel. To this latter an india-rubber tube is attached. The
vessel so constructed may be packed with any appropriate filtering material, but
I prefer to introduce clean and moderately compressed sponge into the inner cylinder,
and granulated animal charcoal into the middle cylinder.
When the innermost cylinder is subdivided, or when an additional cylinder is
introduced, one of the metallic substances which have the power of promoting
oxydation, such as the carbide or silicide of iron or platinum in its spongy con-
dition, may with advantage be introduced into the outermost of the three cylinders
so formed.
The junctions of all rims in the above apparatus may be easily made water-tight
by forming screw threads on them, or by fitting them on over pieces of linen, or by
applying india-rubber bands over their edges. To bring the filter thus constructed
and packed into operation it is only necessary to fill a tub, bucket, or other con-
venient vessel with the liquid that has to be filtered, and to place the filter in the
liquid, on the surface of which it will float. In the course of a few minutes, as the
liquid finds its way into the filter, it will sink down to a permanent level, and if the
mouth is applied to the free end of the india-rubber tube, and the latter is sucked
and then allowed to hang sufficiently over the edge of the vessel to form a syphon,
the liquid will continue to flow until the vessel is emptied. The flow of the liquid
in the tube may be readily regulated or arrested by applying some form of tap to
the free end, or by placing a clip on the tube. The use of such an appliance is
essential to the effective action of this or any other form of filter, inasmuch as it
is only by regulating in this way the rate of flow of liquid through the filter bed
that the same material can be made to efficiently filter liquids of different degrees of
turbidity.
The second object of this Invention is to apply one of the principles embodied
in the foregoing apparatus, viz., the collection of the liquid which has to be filtered
from the surface instead of from the bottom, as is done in ordinary filters, to filters
of some size which cannot conveniently be made to float, or where for other reasons
a floating filter is impracticable or inexpedient. For this purpose I construct n
vessel in the same way as above described, but without the air chamber, and to the
inlet pipe of the filter I attach an india-rubber tube, to the other end of which is
connected a piece of metal or other pipe with perforations therein. This piece of
pipe acts as a catchment to supply the filter, and is made to float just beneath the
surface of the water or other liquid by connecting it with a piece of cork or with a
suitable hollow vessel. In this way all the liquid which enters the vessel is derived
from the uppermost layer of the fluid, so that whilst the filter is in action the liquid

page_text: is spontaneously clearing itself by the process of precipitation of a certain amount
of its suspended impurities, and thus lightening the work which the filter would
otherwise have to do.
Instead of placing the cylinders concentrically within one another, they may be
placed side by side, connecting the first and second at their upper parts, the second
and third at their lower parts, and so on alternately up and down, so as to compel
the liquid to traverse the full length of the whole series. One set of ends of the
tubes must be open, and must have tightly fitting covers applied to them, so as to
allow of the tubes being charged and cleansed when necessary; the other set may
be permanently closed. It is not necessary in order to carry out this part of my
Invention that the flexible tube which is connected with the floating feed described
above should be attached exclusively to the form of filter just referred to; it may be
applied to any filtering arrangement which is so constructed as to allow of the liquid
being led into it by means of such an appendage.
The third object of this Invention is to increase the efficiency of an appliance
which is described in the Specification of an Invention for improvements in filtering
and purifying water and other liquids, and an apparatus for that purpose, for which
Provisional Protection was granted to me on the 18th of January 1876, No. 181,
and which Invention is designed to promote the further purification of water or any
other liquid which is capable of being treated in this way after it has passed through
the foregoing or any other form of filter by exposing it to the action of animal
charcoal, or any other substance possessing similar properties, in such a way that
the charcoal is alternately bathed with air and water, thus enabling it to act under
the most favorable conditions possible. For this purpose I take a cup-shaped
vessel, in the floor of which I fix a syphon tube of sufficient calibre to prevent any
drops of liquid remaining in it after it has operated. It is important that this
condition should be carefully observed, otherwise the syphon action will not be
completely broken, and the vessel when once emptied will not fill again, but the
liquid will run through it continuously instead of intermittently. For the same
reason the size of the syphon tube should be large enough to enable it to run off the
water or other liquid in the vessel with sufficient rapidity (at the maximum rate at
which it is likely to be run into the vessel) to effectually break the syphon action
each time that the vessel is emptied, otherwise the vessel will not empty itself, and
the liquid will run through it continuously when full. The upper border of the
syphon tube should be nearly level with the rim of the vessel, so that the largest
possible amount of liquid may be run off each time. I then surround the syphon
tube with a perforated diaphragm in such a way as to divide the cavity of the
vessel into two nearly equal chambers, vizt, an outer quoit-shaped one and an inner
circular one, in which latter is the syphon tube. The outer chamber I pack with
animal charcoal or other material possessing similar suitable properties. I then
adapt a cover to the vessel, having a tubulure near its margin, so that any liquid
which enters by the tubulure shall fall upon the charcoal; and I make the cover
water-tight at its edges by means of a screw thread, india-rubber band, or other
appropriate means.
In order to prevent the syphon action failing in case the liquid passing into the
vessel dribble so slowly as not to effectually start the syphon, I attach to the bottom
of the syphon tube outside the vessel another syphon tube of such a size that any
drops which dribble over the neck of the first syphon shall accumulate in the
second, and shall without fail start it into action, when it will in so doing drag the
liquid in the vertical tube of the first syphon suddenly over the neck, and thus start
it also.
The operation of this vessel, which I call an aërator, will be sufficiently obvious.
When liquid is led into the tubulure from either of the filters described above, or
from any other, at a rate proportionate to the size of the aërator and of its syphon
tube, the liquid will first permeate the charcoal in the outer chamber, on which it
falls, from which it will then drain into the inner chamber or well. It will then
rise gradually in both chambers until it reaches the neck of the syphon, when it

page_text: will begin to flow, and the well will be rapidly emptied. This will then be
replenished gradually as before by the liquid in the charcoal, which will drain into
it, and as this drains out of the porous charcoal air will follow it, and so bathe that
substance with a fresh charge of oxygen. This process will go on so long as
liquid flows into the aërator. The aërator thus constructed may be placed so as to
rest upon the top of a jug, decanter, pitcher, or other vessel into which the liquid
has to be filtered; or it may be adapted to fit into the top of a receptacle specially
constructed to hold the liquid which is passed from any kind of filter. It is
therefore generally adaptable to and calculated to increase the efficiency of any kind
of filter.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Francis Thomas Bond in the Great Seal Patent Office on the 5th
January 1877.
FRANCIS THOMAS BOND, of Gloucester, in the County of Gloucester, Doctor of
'Medicine. "IMPROVEMENTS IN FILTERING AND PURIFYING WATER AND OTHER
LIQUIDS, AND IN THE APPARATUS EMPLOYED THEREIN."
The object of this Invention is three-fold,-
First. To construct a vessel which shall float upon the water or other liquid
which has to be filtered, and whilst so floating shall, by syphon action through a
tube attached thereto, filter the water or liquid in which it floats. For this purpose
I construct a vessel preferably (though not necessarily) of cylindrical shape, and
consisting of three cylinders of graduated size fixed one within the other in the
following way-The innermost cylinder is open at one end and closed at the other.
To the open end a cap is adapted so as to close it in a water-tight manner. The
cylinder thus formed is fixed in a water-tight way (preferably by soldering if the
vessel be made of metal) in the bottom of a somewhat larger cylinder, the top of
which is open, and in such a manner that its open bottom end (to which the cap is
attached) is fixed in the closed bottom end of the second cylinder, and projects for
a short distance through it. The open top of the second cylinder is attached to
the inside of the closed top of a third cylinder (which is open at the other end) in
such a manner (by the latter cylinder being adapted to the former by means of a
rin) that the one can be separated from the other, or that they can be kept united
in a water-tight manner. The outermost cylinder, which, when the vessel is
standing in its naturally vertical position, is closed at the top and open below, does
not extend for more than two thirds of the way down over the second cylinder,
and forms from the way in which it is constructed an air chamber, by adapting the
capacity of which to the size and weight of the vessel the latter can be buoyed up
on the surface of the liquid. A small tube enters the side of the innermost
cylinder close to the bottom where the cap is attached, and this tube is prolonged
in a vertical direction for a short distance upon the outside of the second cylinder.
By this tube liquid enters the innermost cylinder whilst the vessel is floating.
The innermost cylinder communicates with the middle one by means of a small
vertical tube, the upper end of which is bent at right angles so as to be applied to
an aperture at the top of the side of the inner cylinder, and the lower end
terminates by means of a free aperture close to the bottom of the middle cylinder,
in which this tube wholly lies.
The innermost cylinder may be divided into two parts by a horizontal perforated
portion, so that three separate kinds of filtering materials can be introduced into
the vessel, viz., two in the innermost cylinder and one in the middle cylinder, in
which case the upper end of the innermost cylinder should be open and have a
water-tight fitting tap applied to it, or an additional cylinder may be interposed
between the middle one and that which acts as the air chamber, in which case it is
necessary to connect the innermost and middle cylinders by an aperture through

page_text: the partition which separates the two at its upper end, and the middle and outer
cylinders by a similar aperture in the partition which separates the two at the
bottom.
Into the centre of the plate which serves as the common top of the middle and
outer cylinders a small tube is fixed, one end being in the middle cylinder and the
other outside the vessel. To this latter an india-rubber tube is attached. The
vessel thus constructed may be packed with any appropriate filtering materials, but
I prefer to introduce clean and moderately compressed sponge into the inner
cylinder, and granulated animal charcoal into the middle cylinder.
When the innermost cylinder is subdivided, or when an additional cylinder is
introduced, one of the metallic substances which have the power of promoting
oxydation, such as the carbide or silicide of iron, or platinum in its spongy
condition, may with advantage be introduced into the outermost of the three
cylinders so formed.
The junctions of all rims in the above apparatus may be easily made watertight
by forming screw threads on them or by fitting them on over pieces of linen, or by
applying india-rubber bands over their edges. To bring the filter thus constructed
and packed into operation it is only necessary to fill a tub, bucket, or other
convenient vessel with the liquid that has to be filtered, and to place the filter in
the liquid, on the surface of which it will float. In the course of a few minutes,
as the liquid finds its way into the filter, the latter will sink down to a permanent
level, and if the mouth is applied to the free end of the india-rubber tube, and the
latter is sucked and then allowed to hang sufficiently over the edge of the vessel to
form a syphon, the liquid will continue to flow until the vessel is emptied. The
flow of the liquid in the tube may be readily regulated or arrested by applying
some convenient form of tap to the free end or by placing a clip on the tube.
The use of such an appliance is essential to the effective action of this or any other
form of filter, inasmuch as it is only by regulating in this way the rate of flow of
liquid through the filter bed that the same material can be made to efficiently filter
liquids of different degrees of turbidity.
The second object of this Invention is to apply one of the principles embodied
in the foregoing apparatus, vizt., the collection of the liquid which has to be filtered
from the surface instead of from the bottom, as is done in ordinary filters, to
filters of some size which cannot conveniently be made to float, or where, for other
reasons, a floating filter is impracticable or inexpedient.
For this purpose I
construct a vessel in the same way as above described, but without the air
chamber, and to the inlet pipe of the filter I attach an india-rubber tube, to the
other end of which is connected a piece of metal or other pipe, with perforations
therein. This piece of pipe acts as a catchment to supply the filter, and is made
to float just beneath the surface of the water or other liquid by connecting it with
a piece of cork or with a hollow vessel. In this way all the liquid which enters
the vessel is derived from the uppermost layer of the fluid, so that whilst the filter
is in action the liquid is spontaneously clearing itself by the process of precipitation
of a certain amount of its suspended impurities, and thus lightening the work
which the filter would otherwise have to do.
Instead of placing the cylinders concentrically within one another they may be
placed side by side, connecting the first and second at their upper parts, the second
and third at their lower parts, and so on alternately up and down, so as to compel
the liquid to traverse the full length of the whole series. One set of ends of the
cylinders must be open, and must have tightly fitting covers applied to them, so as
to allow of their being charged and cleansed when necessary.
The other set may
be permanently closed. It is not necessary in order to carry out this part of my
Invention that the flexible tube which is connected with the floating feed described
above should be attached exclusively to the form of filter just referred to;
it may be applied to any filtering arrangement which is so constructed as to allow
of the liquid being led into it by means of such an appendage.
The third object of this Invention is to increase the efficiency of an appliance

page_text: which is described in the Specification of an Invention for improvements in filtering
and purifying water and other liquids, and an apparatus for that purpose, for which
provisional protection was granted to me on the 18th of January 1876, No. 181,
and which Invention is designed to promote the further purification of water or
any other liquid which is capable of being treated in this way after it has passed
through the foregoing or any other form of filter, by exposing it to the action of
animal charcoal or any other substance possessing similar properties in such a way
that the charcoal is alternately bathed with air and with the liquid, thus enabling
it to act under the most favorable conditions possible. For this purpose I take a
cup-shaped vessel, in the floor of which I fix a syphon tube of sufficient calibre to
prevent any drops of liquid remaining in it after it has operated. It is important
that this condition should be carefully observed, otherwise the syphon action will
not be completely broken, and the vessel when once emptied will not fill again, but
the liquid will run through it continuously instead of intermittently. For the
same reason the size of the syphon tube should be large enough to enable it to run
off the water or other liquid in the vessel with sufficient rapidity (at the maximum
rate at which it is likely to be run into the vessel) to effectually break the syphon
action each time that the vessel is emptied, otherwise the vessel will not empty
itself, and the liquid will run through it continuously when full. The upper border
of the syphon tube should be nearly level with the rim of the vessel, so that the
largest possible amount of liquid may be run off each time. I then surround the
syphon tube with a perforated diaphragm in such a way as to divide the cavity of
the vessel into two nearly equal chambers, viz., an outer quoit-shaped one, and an
inner circular one, in which latter is the syphon tube. The outer chamber I pack
with fragments of animal charcoal or other material possessing similar suitable
properties. I then adapt a cover to the vessel having a tubulure near its margin,
so that any liquid which enters by the tubulure shall fall upon the charcoal, and I
make the cover water-tight at its edges by means of a screw thread, india-rubber
band, or other appropriate means.
In order to prevent the syphon action failing in case the liquid passing into the
vessel dribble so slowly as not to effectually start the syphon I attach to the bottom
of the syphon tube outside the vessel another syphon tube of such a size that any
drops which dribble over the neck of the first syphon shall accumulate in the
second, and shall without fail start it into action, when it will in so doing drag the
liquid in the vertical tube of the first syphon suddenly over the neck, and thus start
it also.
The operation of this vessel, which I call an aërator, will be sufficiently obvious.
When liquid is led into the tubulure from either of the filters described above or
from any other at a rate proportionate to the size of the aërator and of its syphon
tube the liquid will first permeate the charcoal in the outer chamber, on which it
falls, from which it will then drain into the inner chamber or well. It will then
rise gradually in both chambers until it reaches the neck of the syphon, when it
will begin to flow, and the well will be rapidly emptied. This will then be
replenished gradually, as before, by the liquid in the charcoal which will drain into
it, and as this drains out of the porous charcoal air will follow it, and so bathe that
substance with a fresh charge of oxygen. This process will go on so long as liquid
flows into the aërator. The aërator thus constructed may be placed so as to rest
upon the top of a jug, decanter, pitcher, or other vessel into which the liquid has
to be filtered, or it may be adapted to fit into the top of a receptacle specially
constructed to hold the liquid which is passed from any kind of filter. It is there-
fore generally adaptable to and calculated to increase the efficiency of any kind of
filter.
The nature and construction of the apparatus thus described will be rendered
more evident by reference to the Drawings hereto appended, of which Figure 1
represents a vertical section of the first form of my apparatus as it appears when
charged and floating on a liquid in which A is the inner cylinder filled with sponge.
This cylinder is closed at the top, except at the two lateral openings C, C, but open

page_text: at the bottom. To this latter end is applied the cap B. At the bottom of the
cylinder are two apertures connected with the pipes E, E, through which the liquid
enters the cylinder A. Having thus entered the cylinder the liquid passes up.
through the sponge with which the cylinder is packed through the apertures C, C,
into the tubes F, F, by which it is conveyed into the second cylinder G. This
second cylinder is open at the top, and closed at the bottom, and is packed to
within a short distance of its upper margin with charcoal. The third cylinder His
open at the bottom, but closed at the top, and is provided with a rinn K, by which
it can be applied in a water-tight manner, so as to cover the upper and open end of
the second cylinder G. In the centre of its upper surface is fixed a pipe L. The
lower end of this pipe reaches to within a short distance of the charcoal in
cylinder G, and to the upper end is attached a piece of india-rubber tubing M,
through which the liquid passes off. It will be seen that the upper part of the
cylinder G and the greater portion of cylinder H contain air, which gives buoyancy.
to the apparatus. In order to pack the vessel with filtering materials, or to remove
the same for purposes of cleaning, the cap B is removed from the lower end of
cylinder A, and also cylinder H from the cylinder G by slipping it off at the
rim K.
Another and simpler form of this portion of my apparatus may be constructed by
so modifying the foregoing form that instead of employing three cylinders arranged
concentrically within one another only one cylinder is used, which is closed at one
end, and subdivided into two chambers by means of a horizontal partition which is
perforated with holes or rendered otherwise permeable to liquid, the chamber
nearest the closed end of the cylinder being adapted to contain air to give buoyancy
to the apparatus, and the other being filled with the filtering material. The
position in which the permeable partition is to be fixed, and consequently also the
relative sizes of the chambers, cannot be arbitrarily defined by a description suitable
to all cases, but must as in the case of the apparatus before described be adjusted so
as to meet the specific gravities of the filtering materials, of the material out of
which the vessel is constructed, and of the liquid to be filtered.
In the upper part of that end of the vessel which forms the air chamber is to be
fitted in an air-tight manner a tube with a piece of flexible tubing attached thereto
to carry off the water after it has passed through the filtering material in the same
way as described in the foregoing form of the apparatus. The lower end of the
cylinder is to be left open for the purpose of introducing the filtering material into
the lower chamber, but a cap, plate, cork, or some other form of embouchure must
be adapted to it in the way described in the case of the inner cylinder of the fore-
going apparatus, so that when the chamber is so filled the filtering material may
be prevented from falling out. The liquid may be led into the lower chamber by a
pipe, as in the case of the foregoing apparatus, or the cap, plate, cork, or other
embouchure which closes the lower end of the cylinder may have an aperture or
apertures therein for the purpose of admitting the liquid directly to the filtering
material.
Although there is only one chamber for filtering materials in this form of my
apparatus, this "does not prevent more than one kind of such material from being
employed, as the chamber may be packed with two or more kinds arranged in
layers, and so graduated according to their filtering powers that the liquid whilst
passing in succession through them shall be purged first of its coarser and then of
its finer impurities. Thus fine charcoal may be placed in the upper part of the
chamber, then coarser charcoal below it, and, beneath all, sponge. A very convenient
way of carrying out this arrangement is to pack the filtering chamber with charcoal
as first suggested, and then to close its mouth with a well fitting cork, in which is
a good sized aperture, into which a piece of sponge is compressed. All the liquid
which enters the charcoal chamber must first pass through the sponge.
Instead of constructing the vessel in the form of a cylinder it may be made in
that of a cone, so divided that the air chamber shall be in the base of the cone; or
it may be made in the form of a cylinder, terminating in a cone at either end. By

page_text: this means the apparatus floats with greater stability than when it is constructed in
the form of a simple cylinder.
The structure of the form of my apparatus which I have just described will be
better understood by reference to Figure 2 of the Drawings hereto appended, which
represents a vertical section of the apparatus when charged with filtering material,
and floating in the liquid which is to be filtered. A, A, is the body of the filtering
case as described above, which is represented as having a conical form, though it
may if preferred be cylindrical, or partly cylindrical and partly conical, as before
described. B, B, is the cover of the same, which in this case has a slightly conical
outline, though it may if preferred be made quite flat; C is a circular neck in the
cover for the insertion of a cork D, into which the tube E is fitted, this arrange-
ment being a convenient way of fixing the tube so as to allow of its withdrawal it
wished. The air chamber F, F, is separated by the perforated plate G, G, from the
chamber containing the filtering material H. The aperture at the bottom of the
cone is closed in this case by a cork I, in the centre of which is an aperture, which
is filled by a piece of sponge. To the upper part of the tube E is attached a piece
of india-rubber tubing L; this tubing is carried over the side of the receptacle, and
allowed to hang down and form a syphon in the manner represented at G in
Figure 3a, and the rate at which the liquid flows through it may be easily regulated
either by adjusting its length so as to increase or diminish the long leg of the syphon,
or by a screw clip, by means of which its calibre can be diminished.
When the filter thus represented requires to be cleaned it is only necessary to
take the sponge and cork out of the lower aperture, and the cork and tube out of
the upper aperture, and to pour water through the latter, when the filtering
material will be washed out; this and the sponge may then be washed or otherwise
cleansed or renewed and replaced as before.
The advantages of this form of my apparatus are, (1), its simplicity; (2), the ease
with which it can be cleansed; (3), the facility with which the flow of water
through it can be regulated; (4), the fact that being a floating filter it draws its
supply of liquid from the uppermost stratum which is least contaminated by
suspended matters, and whilst it is working the liquid spontaneously purifies itself
to a certain extent of the foreign matters suspended in it by the process of pre-
cipitation which takes place under such circumstances.
I wish it to be understood that I do not limit myself in the construction of this
form of my apparatus to either a conical or a cylindrical form of vessel, as such
vessel may be made in other forms if preferred.
Another and equally simple modification of this form of my apparatus is shown
in Figure 3 of the accompanying Drawings, in which A, A, is a metal cylinder open
at both ends; into one end of this cylinder is fixed in a water-tight manner the
cone B, B; into the smaller end of this cone is fixed a short pipe C, one end of
which projects into the interior of the cone, whilst to the other is attached a piece
of elastic tubing D for the purpose of carrying off the water, as in the foregoing
modifications of this form of my apparatus; E is a cover with a hole in the centre
to allow the elastic tube to pass through, which may be applied over the upper end
of the cylinder; the lower end is closed with a cock F, F, in the centre of which is
made an aperture for the insertion of a piece of sponge G, as before described. The
body of the cone is packed with animal charcoal or other suitable filtering material,
a small piece of sponge or linen being first placed in the apex of the cone to prevent
the filtering material getting into the pipe C.. The apparatus which I have thus
described may be made of any size, but the height of the cylinder should bear to
its diameter the proportion of 3 to 2, or thereabout, according to the density of the
materials of the filter. If made of small size it will be found a very convenient
form of filter for portable purposes.
In the Specification which I have herein-before made of the second method by
which I carry out the object of this Invention I bave described a form of vessel
consisting of two or more cylinders, arranged either concentrically or otherwise, as
in the case of my floating filter, without an air chamber, but with a catchment

page_text: which floats on the surface of the liquid in which the vessel is immersed, and
which is connected with an aperture in such vessel by means of a flexible tube.
It is possible to simplify this form of my apparatus in the same way as I have
shewn that of the first form may be by using a cylindrical or conical vessel divided
into two chambers by a permeable partition in the same way as is done in the
simpler form of my floating filter, or even without a permeable partition but with
a permeable outlet tube. The way in which this may be done will be best under-
stood by a reference to Figures 3 and 4 of the Drawings attached hereto, the former
of which represents this form of my apparatus as embodied in a filter for tanks or
cisterns. In this Drawing A is a vertical section of a portion of a tank or cistern
containing the liquid to be filtered B; in this liquid is immersed a vessel C which
in the Drawing is represented of the form of an ordinary domestic pail, but the
precise shape of which is not material; this vessel has two apertures, one at it's
upper part D, and the other in its side near the bottom thereof at E; to each of
these apertures is adapted a tube which is made to fit the aperture in a water-tight
manner by the aid of a screw thread, piece of cork, or other similar appliance; to
the end of the upper tube which projects beyond the vessel is attached one end of a
piece of flexible tubing F which must be sufficiently long to reach the surface of the
liquid in which the vessel is immersed; the other end of the tubing is connected to
a short metallic pipe which is made to float on the surface of the liquid by adapting
it to any arrangement which will give it buoyancy.
There are several ways by which this may be done, but the method which I
prefer as most simple and convenient for the purpose is represented at H in
Figures 3 and 4. The details of this arrangement are more clearly represented in
Figures 5 and 6, the former of which exhibits it ready for use, and the latter in its
separate parts. In these Figures A represents a tube of metal or other appropriate
material which is closed at one end and open at the other; the closed end is attached
to a disc B of metal or other resisting material; on the outer part of this tube in its
lower two-thirds a spiral groove is turned, and a small nut C constructed after the
manner of a thumbscrew is adapted by means of a corresponding thread in its
interior to work in this groove. The part of the tube between the groove and the
disc is perforated with a number of holes, as shewn at Figure 6. Two circular pieces
of flat cork D, D, of sufficient size to give the requisite amount of buoyancy are
each provided with a hole in their centre sufficiently large to allow of the tube A
passing through them. Between them is placed a piece of sponge, felt, or other
suitable compressible and porous material, indicated at E, Figures 5 and 6, and
between the thumbscrew and the lowermost cork is placed a second disc of metal F
or other resisting substance similar to B with an aperture in its centre corresponding
to those in the corks D, D.
The operation of this arrangement is as follows:-The tube A is first passed
through the aperture in one of the corks D, then through a similar aperture made
in the centre of the sponge or other porous body E, then through the second cork D,
and, lastly, through the metal. disc F. In so doing the lower cork and disc should
be forcibly approximated to the upper pair, so as to compress the sponge or similar
porous material between them. The amount of compression so effected will regulate
the rate at which the liquid to be filtered will pass through the arrangement,
and the corks and discs will be retained in their position by threading the screw C
on the tube, and screwing it up until it touches the metal disc F. The free end of
the tube A is then connected with the upper end of the elastic tubing, before
described, and the liquid on which the arrangement (which, for the sake of sim-
plicity, I shall herein-after call the feed floats) passes in through the sponge or other
porous material to the tube by the apertures therein, and so finds its way down
through the elastic tubing to the main body of filtering material, which is repre-
sented in Figure 3a as contained in the vessel C, before referred to. The tube E,
Figure 3, which is adapted to the lower part of this vessel into which it is inserted,
should be sufficiently long to traverse the diameter of the vessel, and should be
perforated with a number of small holes to allow the liquid to find its way into it

page_text: at all points from the filtering material with which the vessel is filled. This filtering
*material, which may be sand, charcoal, or any other suitable material, may be intro-
duced into the vessel through either of the apertures in which the tubes D and E.
Figure 3a, are inserted. To the free end of tube E a piece of elastic tubing may be
connected, which may be carried over the side of the tank or cistern, so as to
convey the water to any convenient point below. The tube so arranged must
be long enough to act as a syphon, and the flow of the liquid through it may be
regulated either by attaching a tap to the end of it or by means of a screw clip
fixed on any part of it, as at G Figure 3a.
In order to start the filter so constructed it will be necessary to exhaust the tube
of air by sucking, when the liquid will follow and will continue to flow as long as
any is left in the tank or cistern.
Instead of connecting the filter with a tube passing over the side of the cistern
or tank it may be connected with one which passes directly through the side at or
near the same level as the lower aperture of the filter, in which case it will be
unnecessary to suck the tube in order to start the filter.
This
In Figure 4 my method of supplying the liquid to the filtering bed by means of
a flexible tube, and floating feed is represented as applied to a portable filter.
filter consists of a cylindrical vessel A made of metal, glass, or earthenware, and
open at the top. To this opening a cover C may be adapted, so as to protect the
liquid from dust, &c. The vessel is divided into two chambers by a partition B,
which may be either horizontal throughout or, as is represented in the Drawing,
somewhat coned towards its middle, where it must have an aperture. Into this
aperture is fitted a piece of metal or glass tube sufficiently large to convey the
liquid readily from the upper to the lower chamber. This tube must be fitted into
the aperture in a water-tight manner, and so that it can be removed, which may
most easily be done by fitting it in a cork, as is represented in the Drawing at D.
The upper end of the tube is connected by a piece of elastic tubing with the
floating feed H, before described; the lower end is in contact with the filtering
material with which the lower chamber is filled. Near the bottom of the vessel is made
an aperture F, to which is adapted a perforated cylinder E similar to that described
in connection with Figure 3. Into the end of this cylinder, which projects through
the aperture F, a tap is to be inserted for the purpose of drawing off the water.
All the fittings of the tubes connected with the aperture F must be water-tight,
which may be most easily effected in the same way as in the case of the aperture
in the upper part of the filtering chamber, viz., by using corks, though the same
object may be effected in both cases by plates or caps and screws.
The action of this filter will be sufficiently obvious not to need further
explanation.
.
When constructed as described this form of my apparatus has no provision for
storing the filtered water, which when wanted must be drawn directly from the
filter bed. It is however easy to make such a provision by subdividing the lower
chamber of this vessel so as to form beneath the filter bed a receptacle for the
filtered water, with an inlet thereto leading from the filter bed, and an outlet
therefrom provided with a tap for drawing off the water. Such a provision is
exhibited in the form delineated in Figure 8 of the accompanying Drawings.
Both of these forms of filter, viz., in Figures 3 and 4, illustrate the two ways
in which the principle of the floating feed may be applied. They possess similar
advantages to those which I have claimed for the first form of my apparatus,
of which they are in fact modifications, intended to be employed in cases where a
floating filter would be unsuitable.
In the description herein-before given of the apparatus by which I carry out the
third object of my Invention, viz., the more effectual aëration of water and other
liquids which have been filtered by exposing them in a vessel which I have
designated an aërator to the action of charcoal or some other appropriate substance
which is bathed in an intermittent manner with the liquid and with air, I wish it
to be understood that I do not limit myself in the size of the vessel,

page_text: When it is desired to aerate large volumes of liquid the aërator must be con-
structed in the form of a chamber, and instead of being divided into two concentric.
compartments by a perineable cylindrical partition, as I have described, the
partition may run direct from one side of the vessel or chamber to the other so as
to divide the chamber into two compartments of any relative size and shape that
may be found convenient. The syphon tube also by which the liquid runs off may,-
instead of being fixed in the floor of one of the compartments, be fixed in the
wall in such a way that the short leg of the tube is inside the vessel and the long
leg outside.
In constructing the aërator I have found that the object which I had in view as
recommending the connection to the bottom of the long leg of the syphon tube of
a smaller syphon tube can be also accomplished by introducing a small bent tube
into the shorter leg of the syphon tube in such a way that one end of this smaller
tube shall project into the neck of the larger tube, and the other shall be outside
the same at about the same height. The nature of this arrangement will be
rendered more intelligible by reference to Figure 7 of the Drawings hereto
attached, in which A is the larger tube and B the smaller one, which may be fixed
in its position by a ligature, as shewn at C. This arrangement has the further
advantage of allowing a stream of air to be drawn into the stream of water as it
runs off through the syphon tube, and of thereby increasing the aëration of the
liquid which passes through the aërator.
Where the aërator is desired to be employed in the filtration of water for
domestic purposes it may be connected with a modified form of my floating feed
filter in the manner represented in Figure 8 of the Drawings hereto annexed,
which is a diagram in outline of the filter and aërating vessel so combined, with a
sectional delineation of the internal structure of the same.. In this Drawing A is
the filter, B the movable cover of the same, and C the aërating vessel. The water to
be filtered is poured into the upper compartment D of the filter, thence it passes,
in the manner before described, through the floating feed E, and the elastic tube
and pipe connected therewith, into the second compartment F containing the body
of the filtering material. From this it is collected by the perforated cylinder G,
out of which it flows through the tube H, which is supplied with a screw for
regulating it, into the tube I, by which it reaches the third compartment K, in
which it can be stored. This compartment has an air pipe running up the side of
the vessel to the upper margin, as in ordinary filters. The tap I, which is inserted
into this compartment serves to allow of the water being drawn off at once if
wanted, or to allow it to flow into the pipe M, by which it is carried into the
upper compartment of the aërating receiver C. This compartment is separated
from the lower compartment by the horizontal partition N, N, in the centre of
which is fixed the syphon tube Ŏ, which has connected with its short leg a smaller
bent tube in the manner before described. The upper compartment is subdivided
into two sections by a partition represented in section at R, R, with apertures
around its base, as specified above. The outer section is filled with roughly
granulated charcoal, the inner contains the syphon tube. The water which enters
the aërator by the tube M passes through the charcoal from P to Q, and when it
rises in Q to the level of the neck of the syphon flows off by it into the lower
compartment of the receiver S, whence it may be drawn off by the tap T.
I consider that part of the foregoing apparatus which is embodied in the
regulating contrivance, figured at H as a screw, for the purpose of regulating the
flow of liquid from the filter bed into the receptacle, as most important, since it
enables the work of the filter to be brought thoroughly under control, a condition
which is essential to an effective filter. This object may be effected equally well
by any form of tap or other contrivance which will allow of the flow of the liquid
from G into L being regulated.
The compound filter and aërator thus constructed possesses all the advantages
herein-before described as belonging to each of these forms of appliances singly,
with the further one, that as the filter and aerator are separate vessels they can be

page_text: easily taken apart for cleaning, and may be used independently of one another if
required.
Having thus described separately in all their details the several forms of
apparatus by means of which 1 effect the object of my Invention, and also a
method by which the principles evolved in each may be combined and applied, I
wish it to be understood that I claim as the novel features of my Invention the
following, viz.
"
floating
(1). The use of the arrangement which I have herein designated as a
feed constructed so as to collect the liquid to be filtered at its surface by floating
therein, and to filter the same in a preliminary manner before transmitting it to
the main body of the filter, as described herein-before.
(2). The use of charcoal or other suitable substance for the aëration and puri-
fication of water or other liquids to which it may be applicable in a chamber or
vessel so constructed that the purifying substance can be bathed alternately with
the liquid and with air on the principle known to sanitary engineers as that of
"intermittent downward filtration" by means of a syphon appropriately fitted in
the said chamber or vessel.
(3). The use of a syphon tube, with a smaller tube connected therewith, as
herein-before described, for the purpose of rendering the action of the larger tube
more effective, and of introducing a stream of air into the liquid as it flows
through the syphon.
(4). The combination of the foregoing arrangements in the manner and for the
purpose herein-before described.
(5). The construction and use of each and all of the forms of apparatus, which
I have specially described, in the manner and for the purposes herein-before
illustrated and specified.
In witness whereof, I, the said Francis Thomas Bond, have hereunto set my
hand and seal, this Fifth day of January, in the year of our Lord One
thousand eight hundred and seventy-seven.
THA
DOND