A METHOD OR METHODS OF PURIFYING, CLARIFYING, REDUCING, SEPARATING, AND DECOM- POUNDING FLUIDS
Year: 1802

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, JOHN
WILSON, of Saint Albans Street, in the Parish of Saint James, Westminster,
in the County of Middlesex, and now of Tufton Street, in the Parish of
Saint John the Evangelist, Westminster, in the said County, Gentleman,
sendeth greeting.
WHEREAS, the said John Wilson did, by his Petition, humbly represent
unto His present most Excellent Majesty King George the Third, that the
Petitioner had, by application. and study, discovered and invented "A METHOD
OR METHODS OF PURIFYING, CLARIFYING, REDUCING, SEPARATING, AND DECOM-
POUNDING FLUIDS," which would be of great public utility, and therefore prayed
that His said Majesty would be pleased to grant unto the Petitioner, His
executors, administrators, and assigns, His Royal Letters Patent for the
sole manufacturing, making, vending, and exercising the said Invention,
within that part of the United Kingdom of Great Britain and Ireland called
England, the Dominion of Wales, the Town of Berwick-upon-Tweed, and the
Isle of Man, for fourteen years, and that His said Majesty was graciously
pleased to condescend to the Petitioner's request, and did therefore, by His
Royal Letters Patent, bearing date at Westminster, the Eighth day of May,
in. the forty-second year of His reign, give and grant unto the said John
Wilson, his excentors, administrators, and assigns, His especial licence, full
power, sole. privilege and authority, that he, the said John Wilson, his
A

page_text: executors, administrators, and assigns, and every of them, by himself and
themselves, or by his and their deputy or deputies, servants or agents, or
such others as he or they should at any time agree with, and no others,
from time to time and at all times thereafter during the term of fourteen
years therein expressed, shou'd and lawfully might make, use, exercise, and
vend his said Invention, within that part of the United Kingdom of Great
Britain and Ireland called England, the Dominion of Wales, the Town of
Berwick-upon-Tweed, and the Isle of Man, in such manner as to him, the
said John Wilson, his executors, administrators, and assigns, should in his or
their discretions seem meet, and that he and they should and lawfully might
have and enjoy the whole profit, benefit, commodity, and advantage from time
to time coming, growing, accruing, and arising by reason of the said Invention
for the term of years therein mentioned; to have, hold, exercise, and enjoy the
said licence, powers, privileges, and advantages unto the said John Wilson,
his executors, administrators, and assigns, for the term of fourteen years
from the date of the said Letters Patent, according to the Statute in such case
made and provided; in which said Letters Patent is contained a proviso, that
if the said John Wilson shou'd not particularly describe and ascertain the
nature of the said Invention, and in what manner the same was to be per-
formed, by an instrument in writing under his hand and seal, and cause the
same to be inrolled in His said Majesty's High Court of Chancery within six
calendar months next and immediately after the date of the said Letters
Patent, that then the said Letters Patent, and all liberties and advantages
thereby granted, should utterly cease, determine, and become void, any therein-
before contained to the contrary thereof in anywise notwithstanding, as in
and by the said Letters Patent, reference being thereunto had, will more fully
and at large appear.
NOW KNOW YE, that in compliance with the said proviso, the said
John Wilson doth hereby describe and ascertain the nature of the said
Invention, and in what manner the same is to be performed, as follows (that
is to say):-
As the present Invention embraces different objects, it may be conducive to
the more clear understanding of the detail of the several methods to mention
some of the general principles:-
First, Clarification of Fluids. This has been repeatedly attempted in very
distant times and places by means of powders, either by passing sand, pounded
glass, and other insoluble powders through muddy water, or by passing the
water through insoluble powders; and many machines, applicable to the
clearing of water, have been constructed without beneficial and permanent

page_text: effect, chiefly because a comparatively small quantity of mud, or other impal-
pable powder, will render any effectual filtre of powders nearly impervious to
fluids; and though several contrivances have been used for supporting the:
powders in their proper situation, no effectual means have been hitherto:
applied to exclude the mud from the body of the filtre, and to prevent the
derangement of the powders by the passing fluid. Of this description are the
filtering wells used in Turkey, the machines proposed by Professor Parrott, of
Paris, and by several other persons. The principles on which a permanent
and effectual filtre of powders must be constructed are, to compress the powders
into the machine or vessel, so that the fluid may pass through the interstices,
but shall not materially remove or derange the powders; to guard the point
where the fluid enters on the powders, so that the powders shall not issue nor
the mud be admitted into the body of the filtre; and to guard the point where
the fluid issues from the filtre, so that the powders shall not be deranged by the
passing fluid, nor any part of them issue along with the clarified fluid.
The said John Wilson does not claim an exclusive right to make clarifying
filtres of powders, as hitherto practised, but he claims the Invention of
applying guards and strainers to filtres of powders according to the above
principles, and likewise the particular guards and strainers herein-after
described; under this head may be included the filtering of fluids through
otlier fluids, whether dense, or elastic and compressible as aerial fluids.
Second, Purification of Fluids.-Charcoal of wood reduced to powder has
been repeatedly employed of purifying of putrid water, in the same manner as
sand, and other insoluble powders for clarifiing it, either by passing the
charcoal through the water, or by making the water pass through the charcoal."
Professor Lowitz appears to have been the first person who observed the pro-
perty which charcoal or wood posesses in purifying and sweetening putrid
water in particular. His process was, to mix the finest powder of fresh made
charcoal with the water, adding a small quantity of vitriolic acid, and to
decant or draw off the fluid when it had become clear by repose. Other
chemists have since employed the same substance in different ways, and have
observed its effects in purifying many other bodies besides water.. Several
attempts have also been made to employ it in filtering machines for domestic
and economical purposes in sweetening putrid water, of which the most
remarkable are those proposed seven or eight years ago by Richard Younger,
formerly a brewer in Edinburgh. His method was, to place a false bottom of
flannel on a frame driven into and fixed in a cask, so as to leave an empty
space between the flannel and the real bottom of the cask. After placing a thin
layer of sand and then of garden mould upon the flannel, he filled the remainder

page_text: of the cask nearly to the top with charcoal dust, mixed with gross pieces
of charcoal, the refuse of the retailers, and then covered the whole with
another thin layer of sand, upon which was placed a false head of flannel
stretched on a frame driven into and fixed in the cask, so as to leave an
empty space above it. The water was poured in at the top of the cask, and
issued purified (so far as the the apparatus could accomplish its purification) at
the bottom; or, the false head, bottom, and charcoal being arranged nearly as
before, the putrid water was conveyed to the bottom of the cask by a hollow
wooden trunk or pipe placed in the centre, and rose through the charcoal
around the hollow trunk to nearly the top of the cask, from which it was made
to run through slips or folds of flannel hung upon the sides of the cask in
the common manner into a vessel prepared to receive it. Of the first of
these machines, several were made by the said Richard Younger; and James
Smith, formerly a Gunsmith in Glasgow, having been employed by the said
Richard Younger in assisting to put them together, went afterwards to
Paris, and having associated with a citizen, Cuchet, and another person,
obtained, in the year One thousand seven hundred and ninety-eight, or
One thousand seven hundred and ninety-nine, or afterwards, a Brevet
or Patent for purifying water by filtering it through charcoal, and for a
machine for the application of this filtre to domestic purposes. In a printed
pamphlet and advertizement published by them at Paris, Smith is stated to be
the Inventor of the principle, and Cuchet of the machine. It differs from the
first machines made by Younger in the use of inverted vessels, for the purpose
of prolonging the course of the water, and by making the water descend upon
the powders through a hollow leaden pipe of between one and two inches
diameter, and the same heighth, attached or soldered at the top to a hollow
head or box, the segment of a sphere of the same metal about twice that
diameter, the whole having the form of a mushroom. The under part of
the gills of the mushroom was pierced with small holes, over the outside of
which a piece of sponge was fixed; and another morsel of sponge, not
fixed, but removeable at pleasure, was introduced into the hollow pipe
of the mushroom, which was fitted into a box or cylinder placed at the
surface of the powders, so that the waters flowed upon the powders, not
through the flannel, but by raising and descending through an inch or two of
loose or nearly loose sponge. All of these processes and machines are liable
to the same defects as the processes and machines used with insoluble powders
already mentioned. The said John Wilson does not claim an exclusive right
to purify fluids by charcoal of wood, as practised by Lowitz and other chemists,
nor to the use of the machine, already mentioned, as made by Richard Younger,

page_text: James Smith, and Citizen Cuchet; but he does claim the exclusive use of
charcoal in filters made with guards and strainers, such as those applied by
him to filtres of other powders, and also to the use of all other substances
besides charcoal of wood for purifying of fluids, whether employed with such
guards and strainers or not, in so far as the same have not hitherto been prac-
tised, and also to the filtering of fluids not through powders only, but through
other fluids, whether dense and incompressible, or compressible and aerial, as
herein-after described.
Third, Reduction, Separation, and Decomposition of Fluids.-Filtres of
powders and of fluids, whether incompressible or compressible, may be
employed for these purposes, combined or not with the other processes herein-
after mentioned. Thus a filtre of charcoal, or other substance possessing
similar properties, of a sufficient length, might be employed in separating, from
a solution of alkaline liver of sulphur or sulphuret, the carbonate of alkali,
with more convenience and effect than by mixing the solution and retaining it
for a sufficient time in mixture with carbonaceous substances, for which a
Patent was granted to the Earl of Dundonald some years ago, and the same
powders might be repeatedly employed for the same or other purposes. By
filtering oil through water or diluted vitriolic or other acids, or solutions of the
neutral salts, a much greater degree of pressure, depending on the heighth of
the columns of the fluids, may be applied than is conveniently practicable in
any of the modes hitherto used, and similar advantages may be obtained by
filtering dense fluids through compressible and aerial fluids. This Invention
applies equally to substances which are fluid at the ordinary temperature of
the atmosphere as to many of those which may be made fluid by means of
additional heat. The form of the machines or vessels, whether for clarifying
or purifying fluids, may be infinitely varied, without any essential difference.
The fluid may be made to flow upon the powders at the higher part of the
vessel, and passing in a perpendicular or inclined direction, to issue at the
bottom or the lower part of the side of the vessel; or to enter at the bottom
or the lower part of the side, and, passing in a perpendicular or inclined
direction, to issue at the top or top of the side of the vessel; or to enter at
the side of the vessel, and, passing in a horizontal direction, either in a
straight line or in a serpentine, circular, or elliptical course, to issue at
the point most distant from the entry; or to flow.upon the powders in any
of the above modes, and, after passing through them during the whole of
its course in one or more or all of the above directions, to issue at the point
of the powders which shall be most distant from the entry. The velocity of
the operation will be regulated by the pressure, and may be increased or

page_text: diminished by making the receptacle or column of fluid to be purified at a
greater or less height above the point where it enters upon or issues from the
filtre, or, by making use of any other power or pressure, to force the fluid
through the powders. It will be observed, however, that it is in general more
expedient to increase the diameter or width of the rim of the vessel containing
the powders, for the purpose of allowing a greater quantity of fluid to pass.in
the same time, then to apply any considerable degree of pressure by means of
a column of fluid or other mechanical means. The vessels may be formed of
every material that is insoluble and incorruptible in the fluid; viz, of the
different metals coated, japanned, or varnished where necessary, as in copper,
iron, tinned iron, &c.; of stone, of glass, of earthenware, of wood, varnishing
where necessary, or charred in the inside, or lined with thin plates of tin or
.other metal, and of every other substance which can be made to contain and
be insoluble in the fluid; and in large machines, of masonry, banks of clay, and
other substances used for making ponds and reservoirs. In metals, the different
parts of the machine which must be left separate till the introduction of the
powders may be joined together by soldering; but where it is necessary
previously to varnish or japan the metal, the heat employed in soldering
will blister or remove the japan; and though painting and gilding will remedy
the defect in the external appearance, yet where the japan is intended not
merely for show, but to defend the surface of the metal, the defect will remain
in the inside. In such cases a rim or narrow slip of tin or other metal, the
surface of which does not require to be defended from the action of the fluid,
may be soldered to the different parts, which are afterwards to be joined
together before they are japanned, and in that case the rims may be soldered
without hurting the japan on the metal of which the body of the machine is
formed; or the parts may be joined together by nuts, screws, and flanches,
or by means of insoluble cements or varnishes, which is the most convenient
mode in vessels made of glass or earthenware, and other such substances,
covering and impregnating such cements where it is requisite and practicable,
as plaister, tarras, &c., with some resinous or insoluble varnish. For the
simple clarification of fluids, the filtre may be composed of any clean fine and
sharp grit, powder, or sand, that is perfectly insoluble in the fluid to be clarified,
though some sands or powders that are only relatively insoluble, as limestone,
with respect to fluids, may be employed, though not with the same advantage.
Where sands or powders perfectly pure cannot easily be procured, glass, stone,
and other such substances may be reduced to a powder proper for the purpose,
having been freed by washing, sifting, or otherwise, from mud and other
impalpable powders before they are used. When it is likewise required to

page_text: purify the fluid, charcoal of wood, and other substances containing the
acidifiable base of carbone, may be employed, either combined or not, in
mixture with the other powders. The same principle applies to the different
powders in excluding the impalpable dust or mud which would render the
filtre impervious to fluids, but this is subject in some limitation with respect
to charcoal, and other substances which act both by a chemical and mechanical
power; for, as the chemical effect appears to be in proportion to the intimate
mixture and extent of surface of the substances acting on each other, the
charcoal, or at least part of it, should be reduced to as fine a powder as will
allow the fluid to pass through it, particularly in machines of such a size that
comparatively a small quantity of the powder can be conveniently applied.
As different kinds of charcoal, and the different modes of grinding it, produce
very different quantities of impalpable powder, it is impossible to give directions
for the quantity of impalpable dust which may, without injury or with
advantage, be left in the powder otherwise than by trial of the quantity
of fluid which will pass through it under a given pressure; or by
separating part of the impalpable powder by sifting or otherwise, leaving
the grains from the size of the smallet grit or sand to the size or a little more
than the size of a mustard seed, and trying by experiment the purifying
power and quantity of fluid purified in a given time, in comparison with the
tryal of the same charcoal in which the impalpable powder was not at all
separated. The finer the powder is, or the greater the surface which is
exposed to the fluid, and the more intimate the mixture, provided the fluid
passes at all, the operation will be performed with a less quantity and more
effectually, but the filtre will be more apt to choak, and will yield a smaller
quantity in a given time. By prolonging the course of the fluid, where it can
conveniently be done, the impalpable powder may be excluded entirely, or as
compleatly as can conveniently be accomplished in practice. It will, however,
be observed, that the separating of the impalpable powder of charcoal,
where it exists in too great a quantity, is a difficult and expensive operation
in any way that has hitherto been practised, and that in practice a con-
siderable latitude in the fineness of the powder may be admitted. Sound
oak charcoal, ground in a mill to about the size of the powder in which
malt is commonly used, has answered the purpose of a filtre very effectually,
without any sifting or separation whatever, while the case has been different
with charcoal, in appearance the same, reduced to powder in a mortar. From
seven or eight to twenty or twenty-four inches or more in length or course
of the fluids through the filtre, has been employed in fluids of different degrees
of putridity or impurity, and from nine to fifteen inches in length or course

page_text: will be fully sufficient for purifying water, though no certain rule can be fixed,
as the effect will vary according to the state of the materials and the mode
of preparing them. Instead of reducing the charcoal of wood to powder
of a proper fineness, the sawings or raspings of wood may be charred so
as not to be mixed with ashes; and the charcoal of other vegetable sub-
stances, peat or moss, carbonaceous mould, the charcoal of bones, and other
substances containing the acidifiable base of carbon, may be used in powder if
not mixed with any impurity which could be communicated to the fluid. The
chief advantage of the substances last mentioned is to purify; but the fine grit
of charcoal, like other fine powders, will clarify fluids; and, on the other hand,
other insoluble powders will contribute to purify them, by excluding the putrid
molecules. But it is found in general, particularly with respect to water, more
expedient to employ them together, and carefully to cover or defend the inside
of the guards or strainers, herein-after described, by a layer of pure sand or
insoluble powder. The remainder of the filtre may be filled either with pure
charcoal powder, or with the charcoal powder mixed with the pure siliceous or
other sand, or with the two powders placed in alternate layers, or with the
pure siliceous or other sand alone, according to the purpose for which the filtre
is intended. The fluid will pass in a greater quantity in an equal time through
pure siliceous or other sand than through charcoal powder, or will be in pro-
portion to the quanty of pure siliceous or other sand mixed with the charcoal
powder. But where the chief object is to purify a putrid fluid, there is an
advantage in using as great a proportion of the substance possessing the
purifying quality as possible within the space allowed; and, .what is by no
means unimportant, the weight of the machine will be considerably less, the
filtre will be more liable to choak, and the quantity of fluid passing through it
in an equal time not be so great; but if the charcoal do not contain too great
a proportion of impalpable powder, and if it be properly packed into the
machine, the operation will be completely performed. A machine where the
strainers were defended with about one or two inches of siliceous sand, and
the remainder of the space was filled with charcoal powder, has answered
effectually with putred water. The proportion of the powders, where they are
mixed together, must depend on the particular materials employed, and can
only be ascertained by actual experiments on them with reference to the chief
purpose for which the filtre is intended to be applied. The guards or strainers
which are applied to the powders may be composed, first, of sponge, or fine
threads of metal, glass, or other substances insoluble in the fluid, and possessing
the capillary attraction, inclosed in a bent tube rising above the surface
of the fluid, and descending on the powders, with a hole, stopper, or cock
}

page_text: in the upper part of the tube, and not so much compressed as to prevent the
capillary attraction from acting. The fluid, rising through the strainer by the
capillary attraction, will be delivered on the powders. Second, of similar
substances compressed in a box, tube, or colanders, in proportion to the
pressure employed or force of the passing fluid. Third, of thin plates of.
porous stone or earthenware, or metal plates pierced with small boles, and
afterwards flattened or drawn out between rollers or otherwise till the holes or
punctures are reduced to nearly a capillary size. Fourth, of fine sharp sand.
or other insoluble powder contained in boxes or colanders, so as to be occa-
sionally changed and cleaned. The entrance strainer may be made in either
of these ways; but the capillary attraction, porous and metal plates and
powders, are chiefly applicable in the case of corrosive fluids, which would
destroy sponge or other such substances compressed into a colander; though
in that case fine threads of gold, or glass, or other substance indestructible in
the fluid, might be used in a colander. In fluids that are not corrosive, as
water, the best substances that can be employed are common sponge and the
more indestructible species of mosses, which are not apt to decay or corrupt.
In all cases where it can be used, the compressed strainer of sponge appears to
be preferable; where it cannot be employed, porous or pierced metal plates,
or fine threads indestructible by the fluid, compressed in colanders, may be
substituted; and it does not appear that the capillary attraction can be used
with advantage in the exit strainer. In all cases these guards or strainers
must be soldered, cemented, fixed, or attached to or upon the vessels, so that
no fluid can flow upon or issue from the powders without passing effectually
through the guards and strainers; and where the pressure is not very consider-
able, and more than counterbalanced by the weight of the powders themselves,
the whole of the powders in the filtre should be firmly and closely compressed
upon every side by the strainers, and by the vessel containing the powders, so
that they may not be deranged by the force of the column of fluid.
The colanders or strainers into which the sponge or other straining substance
is compressed may be plates of the proper metal or other substance, of a shape
suited to the aperture, placed with the sides at the distance of about a quarter
of an inch from each other, pierced with holes about the diameter of three
sixteenths of an inch (where sponge or other such straining substance is used),
and turned down at the edges, and soldered or otherwise fixed or cemented
together at three of the ends or edges of the two plates, so as to form a box'
between them, leaving an aperture at the remaining end or edge, through.
which the sponge or other straining substance is to be pushed in thin and
narrow slices, and gradually and equally compressed by a proper instrument,

page_text: such as a piece of wood or metal, into the interstice between the two places.
This aperture must afterwards be closed by soldering or by other means, so as
to retain the straining substance in the colander, and prevent the admission of
any fluid upon the powders in any other way than through the compressed
substance. The box is directed to be filled with the straining substance through
an aperture at one end or edge of the plates, because it is at least very difficult to
compress the sponge or other straining substance equally and effectually, so that
it may be depended upon, in any other way; but if it be equally and properly
compressed by any means whatever it will answer the purpose. The thicker
the compressed substance is, the fluid will pass through it with the greater
difficulty; and though the substance may, without much difference, be thicker
or thinner than a quarter of an inch, it does not appear that any greater
thickness could be attended with advantage. They may likewise be formed
of two vertical cylindrical tubes or barrels, the inside of the one being a
quarter of an inch less in diameter than the outside of the other placed within
the former, on the same centre, pierced with holes in the sides, and closed in
every other part except at these holes and the end into which the sponge or
other substance is compressed, which must afterwards be closed as before. In
this case, as the inside of the inner cylinder must form a part of the filtre and
be filled with powders, it should be made of such a diameter as will allow a
passage to a quantity of fluid sufficient to supply the run of the filtre. They
may also be formed by making one side of the colander a part of the vessel,
or a plate fixed into the side of the vessel pierced with holes, with three ledges
or grooves rising from the sides, with a plate sliding into the grooves so as to
be retained at the distance of a quarter of an inch from the other plate or side
of the vessel. The space between the two pierced plates being then filled
with the compressed substance through the open end in such a way that the
grooves or edges shall be compleatly covered on the inside with the straining
substance, the aperture may be closed by another slide or screws, pins, or
otherwise, leaving a greater quantity or proportion of the compressed strainer
at the opening. through which the colander was filled; or the strainers. may be
formed and placed in any other shape or manner not herein-after directed to
be avoided, provided they are sufficiently compressed in proportion to the
pressure of the fluid, and that no fluid shall enter into or issue from the filtre
without effectually passing through them according to the principles before
mentioned. The strainer through which the fluid issues may be placed in any
direction, vertical, horizontal, or inclined. But there is an advantage in
placing the entrance strainer in particular positions. In several respects it is
convenient to place it upon the side of the filtering vessel in a vertical

page_text: position, and at an equal height or lower than the exit strainer.
It may also
be convenient to place it in the bottom of the filtering vessel; but in that case
it will be proper, where air may at any time be admitted or confined below
the outside surface of the entrance strainer, to provide a passage by which
that air may be removed without being forced through the strainer and body
of the filtre, where, it is placed on the top of the filtering vessel, or any hori-
zontal or inclined part of the vessel at which the fluid is made to descend
into the filtre, for which situation the cylindrical strainers, already described,
are peculiarly proper. The horizontal top of the cylinder should be perfectly
close, and the fluid should enter through the vertical sides of the strainer only,
and the surface of the strainer should never be placed in such a situation as
to expose it to be covered with a layer of descending mud, as it would be if
placed horizontally or in an inclined position, opposed to a current of descend-
ing fluid. In all cases, where necessary, a receptacle for the deposite mud
should be left, of the depth of one or two inches below the entrance strainer,
and if it can be conveniently done, of the depth of five or six inches; and
means should be provided for clearing out the mud either from the top, or
through passages closed with plugs or screws, which may be occasionally
opened, or by any other means. Similar means may be adopted for wiping
or cleansing the surface of the entrance strainer by means of a moist
cloth, sponge, or
other such substance fixed to a flexible or other
.handle, where that cannot also be done from the top. In many cases it
will be of advantage to place a separate strainer, compressed on the same
principles, and filled or not with a small quantity of insoluble. powders,
in a moveable funnel or bucket, or at the entering leg of a syphon, where
it can be most easily cleansed, so as to remove the grosser impurities of
the fluid before it be admitted on the entrance strainer of the filtre. The
apertures on, which the strainers are placed are in general the most convenient
places for introducing the powders into the filtre, but they may be introduced
The
at any other opening, which must afterwards be completely closed.
degree of compression employed in packing the strainers and of the powders
A very
.will depend on the circumstances under which they are to be used.
thin strainer, not at all or very slightly compressed, will neither exclude mud
nor prevent the derangement of the powders under a convenient degree of
pressure. In every case the degree of compression must be suited to the pressure
of the column of fluid. A strainer compressed by the force of a man, and
which has been used with effect under the pressure of two or three feet of water,
might not be sufficient under a much greater pressure, and under a pressure
of a few inches it would hardly allow any fluid to pass. The surface of the

page_text: a
strainers may be greater or less, as circumstances render expedient; but in
general it will be proper to make them of a sufficient size nearly to supply the
run of the filtre under the degree of pressure that is applied, and the run or
quantity of fluid which will pass through the filtre varies, both according to
the kind of powder employed, and the manner in which it is to be prepared
and packed in the filtre. In filtering of fluids through other fluids, strainers
are not essential, though they may be applied with advantage. In filtering
lighter dense fluid, as oil, through a heavier dense fluid, as a solution of
sulphuric acid or neutral salts, the oil placed in a higher vessel may be con-
veyed by a pipe or syphon to the bottom of the solution, so as to issue through
small tubes or holes in a box, or otherwise, and rise in globules or threads
through the solution, and when at a certain heighth, be allowed to run
into other vessels. The time, the velocity, and the pressure may be accu-
rately regulated by the heighth of the fluid in the filtering vessel containing
the solution, and increasing or diminishing the proportionably higher column
of oil conveyed from the vessel which contains it by the pipe or syphon. In
this way any required degree of pressure and agitation may be effectually
applied with little manual labour, and the lighter fluid may afterwards be
made to pass, if necessary, through a filtre of charcoal or insoluble powders.
In filtering a dense fluid through a compressible and acrial fluid as water,
through airs or gases, the column of dense fluid may be conveyed by a pipe
or bent tube into the vessel containing the airs so as to fall from the top
through small apertures in a box or otherwise in thin threads or drops through
the gases, and issue by a pipe at the bottom, rising to a less height than the
vessel from which the dense fluid was at first conveyed. The p
e pressure, velocity,
and agitation may be regulated by the proportional heighths of the column of
fluids, and in either case any other mechanical power may be employed instead of
the columns of fluid. By filtration alone through powders or fluids, as already
mentioned, a separation and decomposition of particular fluids and of other
bodies may in many cases be obtained; but when joined to another process,
in which the machines that have been described remove more than one
inconvenience, it may be obtained in many more, and in some of consider-
able importance. This process or principle of decomposition is the putrid
fermentation of which, in its application, the said John Wilson claims the
exclusive right. It may be applied in a variety of cases, and in particular, the
putrid fermention, when pushed sufficiently far, will compleatly destroy and
remove the saline matters dissolved in the waters of the sea, and leave it in
such a state as to be rendered perfectly pure, fresh, and sweet by passing it
through a purifying filtre of charcoal. Sea water, without mixture with other

page_text: substances, very speedily and almost immediately partakes of the putrid
fermentation, and it is impossible to preserve it pure, either in reservoirs or
in casks, for any length of time. That the decomposition which takes place
arises from the putrid fermentation is evident from this, among other cir-
cumstances, that the bilge water of the sea is at all times more nauseous
and offensive to the senses than the bilge water of fresh water. The com-
pletion, however, of the putrid fermentation is slow, & a principle seems to be
developed in the process which checks the rapidity of its progress in a state of
rest. It so happens, however, that the situation in which the promoting
of this fermentation will be of the greatest utility is precisely the situation
the most favorable to it, namely at sea, in the hold of a ship. There the fluid
passes in small quantities, and as it were filtres under considerable pressure
through the sides of the vessel, carrying with it the fine particles of the substances
through which it passes, whether resinous, oily, or mucilaginous, which are
for the most part more or less putrid, and is all the time agitated and exposed
in thin layers to the influence of the air in the vessel, and to the airs and
gases which are continually extricating. It thereafter deposits itself in a
situation where it is not liable to be speedily carried away by evaporation;
where therefore it can be allowed without danger or inconvenience to remain
in its original situation it ought to remain, as the process will proceed there
with equal or greater velocity than in any other place; but where that cannot
be permitted, it may be put into vessels, as nearly as possible in similar
circumstances, communicating with the external atmosphere by means of a
pipe or funnel only, and occasionally agitated either by itself, or with other
putrid substances, similar in quantity and kind with those found in passing
into the hold or in the hold of a vessel. The annexed Drawings of some of
the machines are intended merely as examples of some of the modes in
which the principles before mentioned may be applied, without in any respect
limiting to them the infinite variety of forms in which they may be applied.
Figure 1. A, splay cask to contain the fluid to be filtered and the filtering
vessel. B, a smaller splay cask, the broad end uppermost, containing the
filtering matter, the ends of three of the staves being left like the feet of a
bucket at the narrowest end to stand on the bottom of the larger cask, and to
be fastened there by clamps of wood or otherwise. The top of the cask is
5 also secured by clamps or wedges of wood so as to stand at a little distance
all round from the side of the outer cask, leaving a sufficient space for the
passage of the fluid. C, C, entering strainers placed all round on the sides of
the cask B, several in number, immediately above the narrow end, or which
may be placed in the narrow end or head. D exit strainer, which differs from

page_text: the entrance strainer in having a close box or plate fastened on the edges of
the pierced plates, so as to make a reservoir or passage for the filtered fluid,
into which it cannot enter except through the straining substance in the
pierced plates, with a pipe secured by screws, nuts and flanches, which carries
the purified fluid from the reservoir through both casks to issue from the cock
which is screwed into the pipe. In all the Figures the space between the
pierced plates is supposed to be filled with properly compressed sponge..
E, a cock, which may be a screw flanch and blank nut, or plug for clearing
out the mud, and of which one or more may be left for that purpose, and for
wiping the outside of the entrance strainers. F, a moveable bucket into which
a previous strainer is fixed, to purify the fluid from gross impurities before it
passes into the vessel A, fixed in the bottom of the bucket by a nut, screw, and
pipe the broad side of this strainer is represented. This bucket is applicable
in most of the other Figures, though not delineated. G, Figure 1, No. 2, a
vertical section of the side of that strainer consisting of four plates joined
at the edges, the space a between the innermost plates being open and
communicating with a pipe, and through which the fluid runs into A. The
spaces b, b, are filled with pressed sponge, so that nothing can pass from the
bucket into A without passing through the sponge at the aperture marked by
dots. The vessel B may be filled with the powders, either through the holes
left for putting in the strainers, the exit strainer being previously introduced, or
a hole may be made for the purpose at the widest or narrowest end of the cask,
and afterwards stopped with a false head driven in and secured by screws or
otherwise. In all the subsequent Figures the reservoir of the fluid to be
filtered, the vessel containing the filtering matter where it is inclosed in a
separate vessel, the entrance and the exit strainers, the cocks, plugs, or openings
for clearing the entrance strainers, are all marked with the same letters, as in
Figure 1, or their use is evident from their appearance, the fluid always
entering on the strainer at C, and issuing at D.
Figure 2. The splay cask B is made to fit close into A. C, C, are cylindrical s
strainers of metal, as before described in the Specification, with a close horizontal
top the sides of the cylinders are pierced with holes, except that the outer
cylinder is not pierced, or is close for two inches, more or less, above the top of
the cask, to which it is fixed by screws or otherwise. The whole of the vessel B
and the inner cylinder C is filled with filtering matter through the opening on
the head of the cask before the cylinders are screwed down, the exit strainer D
having been previously introduced and fastened in its place. Figure 3, the
sanie, except that the purified fluid is carried from the reservoir under the exit
strainer D upwards by a pipe R to a convenient height to allow a vessel to be

page_text: placed under the cock. Figure 4, the same with the last, except that there is
only one splay cask made use of, the fluid to be purified being separated from
the filtering matter by a division or head II, placed immediately above the
filtering matter, on which head the cylinders C are fixed. In this case, if
the head is placed too low to allow the cylinders C to be conveniently fixed
from the top of the cask after the filtering matter is packed, the powders
must be introduced and packed through openings made in the staves of the
cask under the head H, and which openings must afterwards be made per-
fectly close by plugs, bungs, or otherwise.
Figure 5. Only one splay cask divided by two heads II, besides the real
bottom. The fluid to be purified is conveyed from the top to under the lower-
most head by a pipe S, fixed by nuts and screws, so as to be perfectly close at
each head. There should be two such pipes, the one opening near the real
bottom, and the other immediately under the lower head II, to permit any air
to escape without being forced through the filtre. There are two or more
entrance strainers C, so as not to weaken the head H, and because they
must be strong enough to support the filtering matter above them, and
they are made so that the lowermost plate of the strainer shall be below
the opening of the pipe by which the air is allowed to escape. This form
may most conveniently be packed with the filtering matter either by an
opening in the real bottom (which must afterwards be closed), and the
apertures on which the entrance strainers are fixed, or by openings, to be
afterwards closed, in the staves between the two heads or divisions H; or
if the space between the lower head H and the real bottom be made ten or
twelve inches, the real bottom might be fixed and hooped after the powders
were packed through the apertures on which the strainers C'are fixed.
Figure 6. The vessel B is of metal, and compleatly fills the splay of the
cask A, except at one side where it is flat, as represented in No. 2, which is a
plan of the top of the vessel B and the exit strainer before the cover T is soldered
down. The line Y in Figure 1 represents a plate parrallel to the flat side,
which divides the vessel into two parts, and which plate is closely soldered to
the top and sides of the vessel, so that no fluid can pass from C where it
enters, except by descending to the bottom of the vessel, going under the
plate or division Y, and ascending on the other side of it to the exit strainer
D, which in this case consists of only two pierced plates, as the passage or
reservoir X is formed by soldering down the cover T. The outside of the
strainers C may conveniently be wiped or cleaned when necessary by a proper
instrument introduced from the top of the cask A. The fluid enters at C,
descends below Y, ascends to the exit strainer D, and issues through the cock

page_text: from the reservoir X. This filtering vessel may be placed in any cask or
vessel, and made of any shape or size that is convenient. The flat side is
made in this machine, because one large vessel is fixed in another by being
closely fitted into it, leaving only the opening made by the flat side for the
admission of the fluid to the entrance strainer, and the space below as a
reservoir for the mud that may be deposited; but it may be made as in the
next Figure, Figure 7, where the vessel B is a cylinder resting on a stand, and
which should be supported by a frame. The fluid enters at C in one. or more
entrance strainers placed round the side and immediately above the bottom of
the vessel, and issues at the top. In Figures 8, 9, 10, 11, 12, M is a screw
flanch on which a syphon N can be fixed to or removed from the vessel B by
a nut and turning joint. The syphon is represented Figures 8 and 9, where A
is a bucket or reservoir of impure fluid, and a previous strainer may be fixed
by a screw on the shortest leg of the syphon at M. As the syphon may be of
any required length, any degree of pressure that may be desired may be
given. The syphon is so formed as to keep the entrance strainer at C free
from air.
Figure 13. A, instead of a cask, is represented as a vessel of earthenware;
B, of metal with plates or divisions Y, similar to those before described,
Figure 6. K, K, is an air pipe formed in the earthenware or of metal, to give
air to the reservoir under the issuing strainer. r, r, are two ledges to support
the metal filtering machine B, the middle space of which, formed by the plates
Y, should be of the same square contents as the division on each side of it; that
is, that there shall be the same space for the running of the fluid between the
two plates as on each side of them. The metal machine B is cemented to
the two ledges, r, and a layer of cement is placed or run in between the
sides of the vessels B and A, so that nothing may pass from the top of the
vessel A into the purified reservoir below B without passing through the body
of the vessel B.
Figure 14 represents an urn and its pedestal, either of the earthenware
or uietal. O is the same kind of previous strainer as has been described
as attached to the bucket F, which is screwed upon the top of the pipe P.
In place of the urn a syphon may be attached to the top-cf the pipe P.
By this pipe the fluid descends and issues at the cock above the strainer D.
The cocks E are for removing the mud or impurities which may be deposited,
and the cock W for letting out any air at the side of the entrance strainer C.
Figure 15 and 16 are represented as of metal; they may be placed over the
edge of a bucket or vessel containing the fluid to be purified. The fluid after
passing the strainer will rise in the powders by the capillary attraction, and

page_text: afterwards descend and be delivered at the cock. Figure 15 may be of any
size. Figure 16 is open at the top, and must not be subjected to a con-
siderable pressure on that account; but if a sufficient quantity of heavy powder
is put on the top, nearly up to the edge of the vessel, it will secure the powders
in the leg of the syphon from being deranged, and it has the advantage of
permitting the powders to be easily changed and renewed.
It is not easy to say which of those Figures are best, as applied to different
purposes. The machine represented Figure 6 appears to be the most compleat
for large machines, but it is the most expensive. The machines in Figures 8,
9, 10, and 11 may be used indiscrimately in cases where they are required to be
of the size that is easily portable. The syphons machines, Figures 15 and 16,
are the most simple; the first may be employed in works of any size, the other
in all cases where it would be convenient occasionally to change the powders.
Though so many Figures of machines have been described as examples of tho
application of the general principles on which a permanent filtre of powders
must be made, it will be observed that the form of the machine is not essen-
tially important to the Invention; that filtres of insoluble powders may be marle
of almost any shape or form whatever, with little difference, except that of
comparative convenience in the use, provided the principles are observed, that
the powders shall be so compressed and packed into the vessel that the fluid,
in passing through the interstices, shall not derange or remove the powders
themselves; that the point where the fluid enters on the powders shall be
guarded and secured by entrance strainers, colanders, or otherwise, as already
described, so that the mud shall not be admitted into the body of the filtre
through the strainers, and render it impervious or nearly impervious to fluids,
and so that the powders shall not, by agitation, reflux of the fluid, or otherwise,
be caused to issue through the entrance strainer, and by emptying in part the
body of the filtre, destroy the state of compression in which the powders should
be in the vessel; that the point where the fluid issues from the powders shall
also be so guarded and secured by exit strainers, colanders, or otherwise, as
already described, so that no part of the powders shall issue with the clarified
or purified fluid, so as either to impair the purity or clearness of the fluid, or,
by emptying in part the body of the filtre, destroy the state of compression in
which the powders should remain in the vessel; and that the machine shall be
so formed as to prevent in a great degree the entry of airs into the vessels,
and facilitate their exit when they are there, by which the machines will not
only last longer, but their operation will be greatly accelerated; that the
particular strainers herein-before described, particularly that filled with equally
and duly compressed sponge, is the best for general purposes, but that any
B

page_text: other which will produce the same effect is comprehended under the Invention;
that the form or material is not essential, the Invention being the production
of the effect by peculiar means already described; and that the vessels should
in every part be perfectly close, except at the guarded entrances and exits, and
except in the particular case of the syphon machine, Figure 16, left open at the
top for the convenience of changing the powders, which, acting only by the capil-
lary attraction, and the legs of the syphon being little below the surface of the
fluid, can never be exposed to a great degree of pressure, and where the weight
of the powders themselves in the upper part of the vessel tends to secure them;
if any openings are left above the surface of the fluid, for the purpose of
allowing air to escape, as may be done in the syphon machines, Figure 15, at
the upper bend of the syphon, that such opening shall be guarded by a suffi-
cient compressed strainer, and a cock or stopper 'above it, which may be
opened or shut occasionally for the introduction of dense or the escape of
elastic fluids; for as the syphon machine, Figure 15, may be made of any size,
and the legs any depth required below the surface of the fluid, and is closed
when once it is filled with 'a current of fluid by the capillary attraction, it no
longer acts by the capillary attraction, but by the pressure of the atmosphere,
'as in any other syphon, and may, of course, be exposed to very considerable
.pressure. In compressing the powders, it is better to pack them in a wet
state.
In witness whereof, I, the said John Wilson, have hereunto set my hand
and scal, this Eighth day of November, in 'the year of our Lord One
Inrolled the same Eighth day of November, in the year above written.