IMPROVEMENTS IN APPARATUS FOR FILTERING LIQUIDS
Year: 1838

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ROBERT
BEART, of Godmanchester, in the County of Huntingdon, Miller, send
greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Letters Patent, under the Great Seal of Great Britain, bearing date at West-
minster, the Sixth day of November, in the second year of Her reign, did
for Herself, Her heirs and successors, give and grant unto me, the said Robert
Beart, Her especial license, full power, sole privilege and authority, that I
the said Robert Beart, my exors, adññors, and assigns, or such others as I,
the said Robert Beart, my exors, adññiors, or assigns, should at any time agree
with, and no others, from time to time, and at all times during the term of
years therein expressed, should and lawfully might make, use, exercise, and
vend within England, Wales, and the Town of Berwick-upon-Tweed, my
Invention of "IMPROVEMENTS IN APPARATUS FOR FILTERING LIQUIDS;" in which
said Letters Patent is contained a proviso that I, the said Robert Beart,
shall cause a particular description of the nature of my said Invention, and in
what manner the same is to be performed, to be inrolled in Her said Majesty's
High Court of Chancery within six calendar months next and immediately
after the date of the said in part recited Letters Patent, as in and by the
same, reference being thereunto had, will more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
Robert Beart, do hereby declare the nature of my Invention and the manner

page_text: Figure 1 represents a suitable vessel for making decoctions of coffee or of
other matters. Figure 2 is a piston, shewn separately; a is a piston, consisting
of a ring of metal or other suitable material, having a groove around its
periphery to receive suitable packing, in order to its moving so closely as to
produce the vacuum or partial vacuum required. Within the vessel to which
it is applied is the filtering material, which may be jean, or closely woven
cotton or woollen fabric, which is stretched over the piston; the edge or external
rim of such filtering materials being turned over leaving an enlarged edge,
in which a cord is run to form packing to enter the groove around the piston.
The filtering medium applied to the piston may be of any suitable material,
depending on the liquid to be operated upon, and the degree of fineness desired
to be obtained. c is a handle applied to the two rods d, d, which are affixed
to the piston e, and by which the piston may be raised; e, e, is a projecting
rim affixed to the bottom of the vessel in order that the person using the
apparatus may place his feet on such rim when raising the piston with his
hand, and thereby conveniently work it; or the piston may be worked by-rack
and pinion or other convenient means, and in this mode the Invention should
be used when applied on a large scale.
Supposing it be desired to make coffee by the aid of my Invention a
small quantity of water is to be put into the vessel to fill up the space to
which the piston does not descend, the piston is then to be put into the vessel
and forced down as far as it will go; and in all vessels which are to be put
on the fire, during the time the piston is in the vessel, there should be stops
to prevent the piston going to the bottom, in order that there may be at

page_text: all times a small quantity of fluid between the bottom of the vessel and the
piston to prevent the heat injuring the piston. The requisite quantity of
ground coffee is to be put into the vessel, and a quantity of boiling water is to
be poured thereon and allowed to stand for a short time, the piston is then
to be raised out of the vessel, by which means the liquor will be filtered.
and be very clear. Or, in place of filtering immediately, the liquor may be
boiled in the vessel and then filtered by raising the piston, or the coffee may
be made in a separate vessel and poured into the one containing the piston,
for the purposes of filtering the same by drawing up the piston. Thus it will
be seen that the piston is at once the means of producing a partial vacuum
and of filtering the liquid submitted to it, aided by the pressure of the
atmosphere.
It will be evident that apparatus thus combined, having suitable filtering
material may be applied to the filtering of various descriptions of liquids,
and the apparatus may be varied so long as the vessel is suitably constructed
for receiving a piston as herein described, and it will be further evident
that in place of drawing up the piston when the liquid is desired to be
filtered the piston may be forced from the top downwards, by which the
grounds of coffee or other matter contained and mixed with the liquid in.
the vessel will be carried down, and the liquid above the piston will be
clear and well filtered. Figure 3 shows a section of another part of my
Invention, which consists of a vessel or apparatus for filtering coffee, in
which arrangement there is a piston or filtering surface similar to that above
described, placed very near the bottom of the vessel, leaving only a small
space between the bottom of the vessel and the under surface of the filtering
material; f is a cock or tap for drawing off the coffee when required. It
should be stated that the piston in this case may have a handle to quicken the
process of filtration by raising the piston, but this is not absolutely necessary,
so long as the parts are arranged properly for readily withdrawing the piston
and filtering material for the purpose of cleansing the same; g is a frame or
stand for the coffee pot or urn, which contains an iron heater, by which the
coffee may be kept heated. It should be understood that it is important that
the piston and filtering apparatus (when the coffee pot or urn is in use) should
be low down in the vessel, in order that the same should be well covered with
the liquid, that the atmospheric air may not pass down; and it is highly
important that the space below the piston should be very small, in order to
contain as little water as will prevent prejudicial effects of heat to the piston;
and it is desirable that the opening of the cock into the vessel should be

page_text: as low as possible, for it will be evident that if the space below the piston-
contained a considerable quantity of water, it would dilute and materially
reduce the strength of the coffee first drawn off. In using this construction of
coffee-pot or coffee-urn, the lower part of the pot is to be filled with boiling
water, the filtering surface or piston is then to be lowered to its place, the
proper quantity of ground coffee put into the vessel, and the requisite quantity.
of boiling water filled in, the coffee pot or urn is then placed on its stand, and
the same is allowed to stand for a few minutes, when the coffee may be drawn
off by the cock or tap, and as the coffee is drawn off the pressure above will
force the liquor through the filtering material. The cover of the coffee pot or
urn is to have a hole as heretofore. It will be evident that in place of an
iron heater a spirit lamp may be used to these coffee-urns.
In making the pistons above explained, I prefer that on the upper surface
there should be a perforated plate or plates of tin, or other metals, and that
the cotton or other material acting as the filtering material should be stretched
over the same. I would remark that I am aware that filtering apparatus
have been heretofore so arranged as by means of pumps or other means to
withdraw the air, and thus to obtain a vacuum or partial vacuum below a
surface of filtering medium affixed within the filtering vessel, and thus
bringing the pressure of the atmosphere to aid in the process of filtration. I
do not therefore claim the right as a new Invention to bring into use the
pressure of the atmosphere where pumps or syringes, or other such means
are used for withdrawing air from under the filtering medium in filtering
vessel.
Having thus described the nature of my Invention, I would have it under-
stood that the apparatus may be varied according to the purpose to which it is
to be applied, and I would have it understood that what I claim as my Inven-
tion, is,-
First, the mode of filtering liquids by means of moving pistons having
suitable filtering materials applied thereto.
And, secondly, I claim the mode of applying filtering materials to coffee
pots or urns, from which the coffee is drawn by means of cocks or taps, and
wheren it is not necessary, excepting for expedition, to cause the piston and
filtering material to move to perform the process of filtration.
In witness whereof, I, the said Robert Beart; have hereunto set my hand
and seal, this Twenty-ninth day of April, One thousand eight hundred
and thirty-nine
ROBERT (L.S.) BEART.

page_text: AND BE IT REMEMBERED, that on the Twenty-ninth day of April, in
the year of our Lord 1839, the aforesaid Robert Beart came before our
said Lady the Queen in Her Chancery, and acknowledged the Specification
aforesaid, and all and every thing therein contained and specified, in form
5 above written. And also the Specification aforesaid was stamped according
to the tenor of the Statute made for that purpose.