An Improved Method of and Apparatus for Filtering.
Year: 1893

page_text: Uate claimed for Patent under sect. 100
being date of first Foreign Application (in 14th Oct., 1892
France),
Date of Application (in United Kingdom), 14th Apr., 1893
Complete Specification Left, 14th Apr., 1893-Accepted, 30th Dec., 1893
Date of Application (in United Kingdom), 14th Apr., 1893
Complete Specification Left, 14th Apr., 1893-Accepted, 30th Dec., 1893
COMPLETE SPECIFICATION.
An Improved Method of and Apparatus for Filtering.
I, JEAN PIERRE PRAT, of 163 Rue Judaique, Bordeaux, France, Chemist, do
hereby declare the nature of this invention and in what manner the same is
to be performed, to be particularly described and ascertained in and by the
following statement :-
In the course of my long practice as a chemist, I have obviously had frequent
opportunities of studying all questions more particularly connected with the defects
of the many filtering methods and of investigating under what new conditions
this important operation should be fiulfilled in order to be applied commercially
on a large scale.
The numerous observations which I have thus been able to gather have proved
to me that outside pharmaceutical and chemical laboratories most of the vaunted
filters are far from being yet finally adopted in practice and from satisfying the
most legitimate commercial expectations.
In the wine and spirit trade in particular, rapid filtering processes are required
whereby these beverages may be preserved from alteration, and losses, these
two defects being due to defective filtrations effected in the midst of the sur-
rounding air.
"
'
From all my experiments, results the conception of a new apparatus which
enables me to attain the object at once, and with such thoroughness that it seems
to me that the principles underlying its construction must forcibly impose
themselves as guides in the construction of most filtering apparatuses.
But the art of efficient filtering does not merely depend on the strict observation
of the chemical laws connected therewith but it claims, to-day more than ever,
the resources which chemistry can have at its command. Hence it becomes
necessary to posess a sufficient knowledge of the chemical composition of each
kind of liquid requiring to be filtered in order to bring with efficiency the inter-
vention of the rational means, which may contribute to effect their purification
or clarification without in the least injuring their quality.
In this respect and while drawing on my chemical knowledge, I have discovered
a very rational process which is quite new and constitutes in connection with my
filtering apparatus a general filtering method which I now propose for immediate
use, being firmly convinced that a certain progress is realized."
i
This method comprises generally the use of several apparatuses the principal
of which are shown on the accompanying sheets of drawings that is to say-
1. A metallic apparatus having a large outflow and designed for wines and
generally for all beverages having a similar spirituous yield.
2. A metallic apparatus for wine or other dregs.
3. An apparatus designed for spirituous liquors whether subtle or delicate; it
may be also used to clarify drinking water.
4. An apparatus designed for the purification and sterilization of drinking water.
Before commencing the description of these apparatuses, it is indispensable for

page_text: the purpose of rendering their special parts and working thoroughly understood
to set forth in a short summary upon what principles they have been conceived
and fundamentally based. Casting aside first of all as absolutely bad in the
majority of cases any filtering method carried out from the bottom upwards and
which can only be effected with the aid of a more or less considerable pressure,
I will only consider here filtering from the top downwards under the pressure of
the height of the column of liquid mass which may be kept constant if needed
by means of small exhausting or forcing pumps, powerful pumps having only for
their object to extract liquids but not to filter them.
Beyond the classic filtering paper which alone supplies liquids in a perfect limped
state, there existed hitherto no fabric either vegetable or animal, mineral or
metallic capable of producing such a result without the intervention of some
insoluble or neutral matter" which would play the part of a paper filter applied
upon any suitable fabric.
It is a fact that if the liquid is only charged with solid and small impurities
everything will pass through meshes. But it will be entirely different if the liquid
is further charged either naturally or artificially with some of these substances
which are insoluble, soft, of low specific gravity and divided into a multitude of
small floating clods or lumps which soon agglomerate together and are uniformly
deposited over the whole surface of the fabric in the form of a more or less thick
layer capable of stopping or acting as a barrier against solid particles even of the
finest size. Henceforward the filter is made. I must still further insist in the
interest of my subject upon the mechanical formation of filters on fabrics. If
instead of amorphous material, textile. or other fibres are made use of and are
properly loosened and disintegrated, such as for instance those of common filter
paper previously reduced to a paste diluted in the liquid requiring to be filtered, it
will be observed that this liquid passes through first in a turbid state, when the
fibres carried away by the flow of the liquid through the fabric stop between its
meshes become narrowly interspersed amongst the same and form thus a multitude
of felt like clods or lumps which spread hither and thither without cohesion over
the surface of the fabric so as to form a pellicle or real sheet of filtering paper
without adhering to it. Textile fibres thus formed upon fabrics are liable to stop
on their passage every solid corpuscule and are consequently eminently fit to make
first class filters. I will indicate further on what material may by reason of its
particular chemical action be best utilized for the manufacture of the most efficient
filters.
Considering the rapidity and constancy of the supply I shall first of all establish
the principle that under equal units of height of the liquid column, the most
potent factor of the speed of the supply is to be found in this condition: that is as
soon as the liquid passes through meshes; it should be free to submit to the force
of gravity and to be able to inmediately fall down in a vertical direction without
being held back by capillary attraction or other influence. Another point of no
less importance consists in preventing by means of a methodical arrangement of
the apparatus, the filtering surface from gradually assuming a pasty consistence
which frequently leads to clogging or choking up by assisting in the stoppage of
filtration. These principles are deducted from a series of experiments which I
undertook with a view to accurately ascertain the conditions under which the
supply may be increased to a maximum. For this purpose I have used various
liquids of different nature while endeavouring to render all things otherwise equal
in my operations so as to obtain comparatively constant results with "plane
surfaces as well as with "circular" surfaces formed on the different fabrics. I
have operated first of all on plane filters arranged vertically and then gradually
inclined these planes in succession until they became horizontal.
""
I have repeated the same experiments with the same liquids in circular filters
having the same units of area as the surface of plane filters, and I started from a
cylindrical form in a vertical direction to an inverted cone form by gradually
developing their bases and hence the angle at their vertex up to the extreme limits.

page_text: It will be understood that all these experiments were only made on filtrations
carried out in the ordinary manner within the surrounding air.
It is not necessary to relate here the results of these long and minute experi-
ments, and hence I will confine myself to a mere indication of the most important
practical facts which were gathered therefrom and which formed exactly the object
of my researches, viz.:
1. All the conditions of the operations which were equal, being carefully
watched the inclination of the plane filters to an angle of from 20° to 40° was
found the most favourable arrangement for a speedy supply and the only one which
enables a maximum to be nearly obtained.
2. Likewise, with circular filters the best form of which is that of an inverted
cone, the maximum supply is obtained when the line traced by its edge corresponds
exactly to the inclination of the plane to the angle of from 20° to 40° above
specified.
3. Under these accurate inclinations, filtering surfaces of equal unit are capable
of preventing clogging and of contributing to the maintenance of a relatively
constant supply; whence should be concluded that in filtrations which are effected
in the surrounding air the filter having the form of an inverted cone would be
superior to all those hitherto used. This is no doubt the reason why the filtering
bag still occupies the foremost place amongst the filters most generally used
although on a restricted scale it doubtlessly owes this advantage, to its being the
filter which best fulfils the conditions just briefly set forth. This filter however is
in principle only the old bag of Hippocrates more or less suitably adapted. But
if time has consecrated its advantages, the defects which limited its use in
practise still exist. As however the filtering or straining bags could not be ma le
of very large size on account of the too considerable weight of the liquid which
these hand implements could not support if they had to be multiplied and hence
become very cumbersome, while their form resembling too much of a truncated
cone greatly retarded the filtration and impeded its brilliant limpidity, while owing
to this operation being effected in the surrounding air the liquids to be filtered could
not be preserved from the alterations and losses in spirit to which they are
exposed. By thus indicating the defects inherent to straining or filtering bags, my
only object is to well set forth here the means by which I have succeeded in
avoiding them radically.
Consideration of the multiplication of filtering surfaces. All things being equal,
the yield of filtrations is constantly in a ratio with the extent of the filtering
surface and is measured proportionately to the units of the latter. It may be
remarked that this principle has been abused in the many arrangements vaunted
now-a-days; these surfaces have been perseveringly subjected to too excessive a
development relatively to the volumes and spaces (which were contrary and too
restricted) of most modern portable and fixed filters. These apparatuses could not
receive too great a stretch of fabric without their folds edges &c. being brought in
too close proximity to one another, however ingenious was the arrangement of the
fabric; it was further obvious that the surfaces being as a matter of fact too con-
tiguous were liable to promote clogging.
From my observations the surface which is most liable to be clogged is that
which is arranged horizontally.
As I have herein before remarked of the present description with reference to
the automatic formation of filtering nets, there is no fabric capable of finely filtering
liquids, alone, especially when they are unsufficiently provided with insoluble
material of the kind above mentioned. Beyond slow filtrations which are effected,
without the aid of their intermediate means, through solid and porous bodies
whether divided or not but in all cases indifferent and inert, the number of the
substances which are indispensably used in the formation of quick acting filters is
very limited. The action of some of those is purely physical and that of others is
successively physical and chemical. I classify them thus, under three heads.

page_text: 1. Material of fibrous texture, inert and acting only mechanically, such as the
very loose fibres of ligneous textile substances and of asbestos.
2. Colloid, soluble or partly soluble substances which, by their chemical action
in the midst of the liquids which they clarify while becoming instantaneously
insoluble, envelop within their coagulum the loose particles which rendered them
turbid, such as proteids and gelatinous substances.
3. Hydrated mineral substances in a physical state of jelly or paste, or anhydrous
and in a nearly pulverulent state; I can only quote one substance of this kind, that
which forms the chief object of my new filtering method, that is, pure anhydrous or
hydrated silica prepared in its various states by a dry or wet process. It is on
account of the above properties that this interesting chemical has the advantageous
feature of being capable of entirely replacing all the above named substances,
wherefore I think it of great importance to at once recommend the use to which I
intend to subject it. Some long time ago, a special study of this substance revealed
to me the very remarkable filtering properties which it possesses to a very high
degree but which are variously manifested under certain conditions from its
anhydrous state after calcination to its colloid state throughout its curious degrees
of hydratation. It is therefore necessary to enumerate here the precious morpho-
logical properties of this body.
In the anhydrous state silica is at once pulverulent and in conglomerated flakes
extremely porous, light, and rapidly absorbing the liquids which appear to make
the flakes swell. In compressed mass, the permeability of this silica remains con-
stant and its pores efficiently stop the corpuscles at its surface. From a chemical
point of view anhydrous silica is entirely insoluble, indifferent, inert and hence
unable to take up anything whatever from the liquids with which it comes into
contact for filtering purposes nor to impart anything thereto.
As a hydrate, silica, rendered previously insoluble, assumes an entirely gelatinous
form which decreases as it becomes hydrated until it takes the consistence of a
short paste efflorescing in the air. It retains in all its degrees the same filtering
properties by endosmosis while its permeability is in no wise diminished by the
loose particles which it stops on the surface of its layer.
Although in all these different states, pure and insoluble silica may be entirely
substituted for any other material having the same property of forming a filter on
fabrics, I am still far from proposing its exclusive use; but I am convinced that in
many cases, the association of the action of silica with that of the other substances
used will help to perfect the filtering art and will render good services.
To terminate this description, I have only now to bring prominently forward the
capital feature which sums it up. It will be seen that it is upon the whole of the
important properties which I have discovered in silica in its different states that I
found or base my new filtering method which with the co-operation of my new
apparatus constitutes the method or system which I now propose for working
purposes.
Description of samples of my apparatus are as follows:-All my metallic
apparatus is exclusively made of copper and of bronze tinned nickelled or silvered
throughout so as to entirely fulfill all bygienic requirements. These apparatus
being liable to assume any size, I will omit to give their dimensions. The shape is
changed when coated with their filtering tissue into that of a long straight cone
truncated at about a third of its height. This truncated form does not decrease
by half its filtering surface as one may imagine, but it has on the contrary the
advantage of doubling it as I am now about to prove.
OX GLACE
T

page_text: traversed by a kind of sleeve or neck C tapped at its lower part while its upper
part carries a copper pipe D soldered thereto and terminated by the key E whereby
the apparatus is screwed at the bottom of a suitable basin through the centre of
which it passes. Around the neck and flush with the plane of the disc A are
arranged at equal distance small openings F for the free outflow of the liquids as
they are being filtered off. To one of these openings leads a bent pipe G which
acts as an air hole and serves for forcing purposes, that is for expelling the internal
air. Another air hole is likewise provided at H towards the upper part of the
copper pipe D. From the grooved hoop bordering the tray A start equidistant
copper rods 1, I, I arranged at a suitable interval according to the diameter of the
hoop, inclined at a predetermined angle and extending as far as the collar J where
they are soldered, being subsequently bent in order to descend in a straight
direction at the angle above mentioned until they reach the tray A, where being
fixed and bent again they ascend still at the same angle as far as the collar of the
key E, and are finally soldered in a bundle. The flanges or blades K consolidate
the apparatus and serve as a support for the fabric. In order to prevent the
drawing from being too complicated I merely represent the flanges or blades which
are in section at their bases by the letter K in Sheets 1, and 2. Upon the lower
surface of the tray A is fixed a flange ring or washer L designed to circularly clip
the fabric forming the base of the cone of the filtering bag and which can be finally
fixed under sufficient pressure to form a hermetic joint by the butterfly nut M
engaging subsequently within the tapped part of the neck.
COVERING OF THE APPARATUS.
From the foregoing, it will be already understood that the metallic cage of this
new apparatus is designed to be covered over either with a fabric, or with felt.
having the form of a long straight cone, which as above stated represents
three times its height as shown in Sheet II by the outline N N of a bag or sleeve
composed of animal, vegetable, mineral or metallic material in vertical section; at
the summit or vertex of its cone is arranged an eyelet allowing only the passage of
the ball or ring of the key E. The covering of the apparatus is effected in a
manner which is as simple as it is rapid, and in three movements it is sufficient as
follows:-
1. To wrap up its central bundle with the sleeve, care being taken to pass the ball
of the key E through the eyelet and then to string-up this extremity of the sleeve.
around the small collar o.
2. To circularly fold down the base of the sleeve over the lower surface of the.
tray A, clip the same with the flanges of the ring or washer L and tighten it.
subsequently with the aid of the thumb nut M.
3. To tightly string up the base of the sleeve around the groove formed for
this purpose at B in the tray A. All that is now left to do is to fold down and
circularly stretch the sleeve thus fixed by its two ends upon the three surfaces
straightened by the rods I which are fixed to the flange or blade K. Thus dressed
up this apparatus is ready to be directly screwed in the centre of the base of a
special cylindrical basin through which passes a bronze nut or what is still more
practical to the short branch of a pipe bent at right angles and the end of which is
adjusted by connecting screws to the outflow tap arranged parallel to the outer
base of the same cylindrical basin.
When the filtering operations are carried out in the open air, this element may
be advantageously substituted for any other having equal units of filtering surfaces
as well as a due proportion in volume. But in this case the question is much more
important, and has for its object to carry out filtrations on a large scale, with the
absolute exclusion of air. This will be henceforward easily realized by the
application of the principles upon which the above described filter is based if its
proper function is added, the important complementary action of the hermetic vessel
wherein it must be fixed at each operation. This vessel, which for a single element

page_text: (samples on Sheets I and II) is reduced to a cylindrical copper basin hermetically
closed, and can be easily constructed, for its principal parts consist simply of the
following:-
-
1. A cylindrical basin the base of which should never exceed more than two
centimetres the diameter nor by more than eight centimetres the height of the
filter.
2. A turned bronze hoop bordering the opening in the cylinder and carrying a.
groove in which accurately fits the hoop of the lid likewise of turned bronze these
hoops being similar to those which connect in stills, the dome or top with the
reservoir while making a hermetic joint.
3. At the base of the cylinder in front view is arranged an opening designed to
make a free passage for the conduit pipe of the filtered liquid after having been
connected to the outflow tap.
4. Upon the left hand side of the base of the cylinder is fixed a tap serving for
the partial discharge or complete emptying of the basin.
5. Upon the right hand side of the base of the cylinder as well as on its corre-
sponding point at the top are arranged two necks bent at right angles and closed
with screwed stoppers which are connected by a glass tube indicating the level and
even the state of the liquid in the apparatus.
6. In the centre of the basin lid is soldered a piece of piping bent so as to be
connected to the feeding tap of the vessel containing the liquid to be filtered.
7. The lid carries moreover on the right hand side a neck furnished with a tap
surmounted by a long glass tube through which the air is completely expelled
from the basin while indicating that the latter is full by the arrival of the
liquid.
8. The lid carries lastly on the left hand side another tubular neck designed to
receive a manometer for the rare occasions when it is required to resort to a suitable
pressure by means of pumps.
The above is all that constitutes my complete filtering apparatuses. I have
only to proceed to its fitting up which is quickly effected in three movements
thus:-
1. I place in the basin of the filtering apparatus previously covered and screwed
by its neck in the mouth of the above mentioned short conduit pipe bent at right
angles hereinbefore mentioned, and adjust its end to the outflow pipe by the con-
necting screws; the latter pipe carries four flat tabs fixed to its base and arranged
crosswise in order to fix the filter in its vertical position.
2. Close the basin with the lid and hold it constantly close by means of three or
four special clamps.
3. Connect lastly the central pipe of the lid with the feed tap. Now there is
nothing more to do but to charge the apparatus and cause it to operate while
observing the rules set forth in the filtering art. It will be readily understood that
such an apparatus, whatever may be its dimensions and the speed of its supply
cannot suffice for filtrations on a large scale; hence the very natural suggestion
occurs to group a given number of them in order to increase the yield, but the
important question of the methodic arrangement of these groups in hermetic basins,
since filtering must be effected without the access of air remained for some time
beset with great difficulties from a practical point of view. I have however
succeeded in removing them by the arrangement I have devised for filtrations;
even in the midst of liquids enclosed in vats having a manhole, this is done
by excluding the hermetic basins otherwise indispensable as I am about to
demonstrate.
A long copper or bronze pipe is provided with a series of equidistant mouthpieces
arranged to receive the necks of my filtering apparatus shown in Sheets I and II
(screwed therein vertically); it will be easily conceived that this pipe may be bent
into a more or less circular, elliptical, ellipsoidal or other form corresponding to the
particular form of each hermetic basin in which each pipe should readily enter
without being provided with the filters which are grouped there.
The two

page_text: extremities of each pipe are joined and soldered at the end of a conduit pipe having
a double thickness and adjusted at its other end, by means of connecting screws to
the outflow pipe of the hermetic basin. Thus fitted in the basin which belongs to
them each of these pipes is now ready to receive and be screwed thereto as many
filtering apparatuses as there are mouthpieces. Basins of elliptic form require
independently of their water gauge and blow off cock two hermetic covers one of
which will carry centrally the neck for the expulsion of air, having a tap and
the other the manometer. As regards the feed pipe which in the cylindrical
arrangement starts from the centre of its lid; it is placed between the two lids in
the centre of the basin.
The filtering apparatus, of Sheet III is designed for wine and other dregs. It
will be noticed in this apparatus that the sleeve or bag only requires to be fixed at
its base, the extremity of its cone being without eyelet simply encloses without
string the central bundle of the apparatus. As it is not absolutely necessary to
filter the dregs without access of air, the apparatus may be placed in wooden vessels
and merely covered up. The same principle, is carried out in tanks or vats, when
the filtration is to be performed in the midst of the liquid contained therein. In
this novel arrangement the tanks or vats must be first considered as having to play
the same part as the hermetic basins which they replace. For this purpose the
arrangement of the apparatus is as follows :-
:-
1. Bending the receiving pipe of the filtered liquid into the shape of an elongated
ellipsoid so as to nearly reach the length of the tank or the diameter of the vat,
the distance between its branches is regulated according to the height of the man-
hole so that the said pipe may be introduced through the same.
This long pipe is
fixed by arched feet; and is connected like the former pipes to a conduit pipe of
double its thickness arranged to be connected to the outflow pipe generally placed
at the base of the manhole door of the tank or vat.
2. The operative who enters the tank or vat to place the said pipe, now screws
in each mouthpiece thereof, the filtering apparatus being gradually passed on to him
by a labourer through the manhole.
2. All the mouthpieces being thus treated, this new apparatus is ready to operate
as soon as its vessel is filled, and to carry out the filtration in the midst of his liquid
with a speed proportional to. the number of elements used. The filtration of
alcoholic liquids of high degree such as rum, brandy &c. as well as of cordials, and
liqueurs, is usually carried out in the same kind of apparatus the filtering surface
of which is relatively too restricted in as much as it is of wire cloth and arranged
horizontally. The wire cloth even when superposed is incapable of yielding above
a fine and brilliant filtrate and requires the addition of filtering paper pulp diluted
in the liquid itself; whence follows, that if by adopting wire cloth the contact of
organie fabrics is sought to be avoided, it is compulsory to use the organic paper
substance as an indispensable intermediate means. It will be undoubtedly more
advantageous under all conditions to apply any filtering method to all this kind of
liquid and the most suitable apparatus to carry out this improvement is simply the
complete hermetic cylinder shown in Sheets I and II furnished with from four to
eight filtering apparatuses arranged in the manner above set forth. As inter-
mediate means I propose the use of silica alone or mixed with filtering paper pulp
according to circumstances. Distillers, and manufacturers of various beverages
and liquorists will soon appreciate the value of my methods and apparatuses by the
services rendered.

page_text: collar D is provided with triangular grooves equal and continuous for each section
of its cone E.
2. This piece ascending from the filter is designed to be entirely covered by a
conical sleeve of asbestos whose ends are fixed around the collars C and D by
means of an asbestos cord.
3. A sleeve F straight or conical of porcelain or porous stoneware, enclosing the
filter throughout its length as shown in the central vertical section of Fig. 1.
On the inner surface of the lower collar D and at the point of intersection of the
angular lines are formed holes G which communicate with the tubular part of the
upright and alow the filtered liquid to flow into its conduit pipe. A similar number
of smaller holes is arranged somewhat below the upper collar H in order to assist
the escape of air subsequently forced downward.
4. The tubular neck projecting from the lower surface of the large collar D is
enclosed in a screw ferrule A I which fixes the filtering element in the tapped
mouth piece J of the conduit pipe K which is of nickelled bronze.
5. A cylindrical basin of enamelled stoneware designed to receive one or more
parts of the apparatus; it is provided with two side handles, with a hole in it's base
for connecting the conduit, pipe to the outflow pipe and with another hole at its
upper part for the overflow, when drinking water charged with inert particles
is only to be filtered. The basin in this case is closed with a plain stoneware lid.
Fitting up of the apparatus is as follows:-
1. Place at the bottom of the basin the circular pipe having tapped mouth-
pieces and connect its conduit branch to the outer outflow pipe while proceeding as
for metallic basins.
2. String up the ends of the asbestos fabric sleeve around their respective
collars C and D by means of an asbestos cord.
3. Screw down the apparatus in the tapped mouthpieces of their common pipe.
4. Enclose each apparatus throughout its length in a sleeve F.
5. Fill or pack with silica in any suitable form, the space between the asbestos
cloth and its sleeve F.
The basin is now charged from the bottom upwards with the water required to be
filtered for drinking purposes. Such is the apparatus which I propose for the
purification of drinking water in accordance with hygienic rules.
For
Manufactures of specialites require to filter liquids which owing to their peculiar
nature are either injured by the prolonged action of air or deprived thereby
through vaporization of too great a quantity of their subtle principle; other liquids
need only be kept from coming into contact with organic matter. An entirely
mineral filtering apparatus, whereby the filtering may be effected sheltered from
the surrounding atmosphere, is absolutely requisite for all these special cases.
this purpose the ceramic basin above described may be readily modified and
converted into a hermetic basin similar to the metallic basins hereinbefore described.
It is sufficient for this purpose to provide the cylindric stoneware basin with a
discharge pipe at its base; a water gauge; and a hermetic cover carrying only in
its centre the air escape pipe; to arrange the whole like the cylindrical metallic
apparatus filtering free from the access of air first described in this Specification.
It will be understood that under such conditions the apparatus can only be
provided in order to completely form the filter with silica exclusively to which the
slag wool or asbestos packing may be added.
Special filtering apparatus for the sterilization of drinking water is as
follows:-
This apparatus which is entirely mineral and necessarily inert is shown in
Fig. 2, Sheet III, and appears at first sight to be a mere modification of the
preceding mineral filter; but, this modification is of greater importance than might
be thought at first, for it is devised under the most favorable conditions considering
its object viz. The daily and sufficiently speedy sterilization of large quantities
of drinking water effected through a layer of pure silica acting like porous earth.
The description above set forth of my improved filtering method will greatly help

page_text: to simplify that of this last apparatus. Fig. 2 shows in vertical section the exact,
although somewhat curtailed form of the support of the preceding filter (Fig. 1.) as
well as its porous sleeve.
Fig. 3, shows the difference i.e. the elements may in this case fit one within the
other and be successively superposed by their tubular end at L and M starting from
the latter which forms the base.
As to the rest of the description and as a guide for mounting the whole apparatus
it will suffice to follow the letters of reference of the apparatus shown in Fig. 1
which are the same as in the sterilizing apparatus in Figs. 2, and 3.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what I
claim is
The combination of everything connected with the principles on which is mainly
based my new general filtering method and the new apparatus, 1 declare expressly
that I intend to claim absolutely all its applications, substantially as herein
described and according to the accompanying drawings.
1
1
CA 1 1000
J. P. BAYLY,
18, Fulham Place, W., Agent for the Applicant.
J. P. BAYLY,
18, Fulham Place, W., Agent for the Applicant.