A NEW OR IMPROVED FABRIC OR FILTER FOR FILTERING CHEMICALS OR LIQUID SUBSTANCES
Year: 1877

page_text: LETTERS PATENT to John Sheddens Campbell, at present residing in the Town
and County of Sligo, Ireland, for the Invention of "A NEW OR IMPROVED
FABRIC OR FILTER FOR FILTERING CHEMICALS OR LIQUID SUBSTANCES." A
communication from abroad by Thomas Ross, of Cape Town, Cape of Good
Hone.
Sealed the 13th October 1877, and dated the 26th July 1877.
PROVISIONAL SPECIFICATION left by the said John Sheddens Campbell
at the Office of the Commissioners of Patents on the 26th July 1877.
JOHN SHEDDENS CAMPBELL, at present residing in the Town and County of
Sligo, Ireland. "A NEW OR IMPROVED FABRIC OR FILTER FOR FILTERING
CHEMICALS OR LIQUID SUBSTANCES." A communication from abroad by Thomas
Ross, of Cape Town, Cape of Good Hope.
"
This Invention relates to improvements in " "filters or fabric to be used for
filtering chemicals or substances of a liquid, viscid, or albuminous nature, such as
nitrate of silver, varnish, or albumen.
The filter at present in use is made of either white or grey bibulous paper of a
porous nature, which, being folded and placed inside of a glass or porcelain funnel
or filter, allows the chemical poured into it to be filtered through it.
But when the chemical is poured in and the filter paper made thoroughly wet,
the line of the filter coincides so exactly with that of the funnel or filter all over
the whole surface, except the extreme apex, filtration is rendered inconveniently slow,
owing to the clinging of the wet filter to the sides of the funnel; and further, owing
to the soft porous nature of the filter paper, great care has to be taken to prevent
the filter paper from breaking, which, with every care frequently happens, thus
causing a waste of liquid and a great waste of time, owing to the necessity of
filtering the chemical over again.
To remedy these obviate defects is the principal object of this Invention, which
consists as follows:-An ordinary filter paper, such as is now in use, being found
the most suitable material; to one side of this filter paper is cemented or otherwise
D

page_text: fixed a piece of netting, muslin, or any other such like material of an open texture,
sufficient to allow the liquids to pass freely through.
The netting or muslin is made to adhere by means of some substance which will
not injure the chemicals to be filtered, but in most cases albumen is the most suitable
substance to use for this purpose, although other adhesive substance may be used,
according to the nature of the chemicals to be filtered.
To fix the muslin to the paper, after being coated with the albumen or cementing
substance, either the one or the other is wetted or damped, and when laid together
a hot iron is passed over them to coagulate the albumen, and also to bring the
netting or muslin in close contact with the paper.
Instead of pressing the netting or muslin to the bibulous filter paper by hot irons,
they may be fed in, either in pieces or in a web form, between hot rollers, so as to
make them adhere, and dry the albumen or other cementing substance at the
same time; and by another improvement these rollers might be fluted so as to
give a fluted or corder surface or effect to the fabric, which would further assist
filtration by exposing a larger filtering surface in the same diameter, increase
its strength, and assist in keeping the filtering material off the supporting surface
of the filler or funnel.
The advantages of these improvements will be obvious, as the netting or muslin
strengthens the filter so that it cannot break by ordinary use, and prevents adhesion
of the filter to the sides of the funnel or filler, thus allowing the chemical to pass
freely through over the whole surface of the filter; another important advantage
being, that the same filter may be used over again frequently, which thus gives by
this Invention a certainty and security of filtration not hitherto obtained. And
liquids of a viscid or glutinous nature, such as albumen, varnish, or gelatine, may be
filtered freely by these improvements, which could with difficulty be filtered at all
by the filtering material previously in use.
The Invention thus combines the qualities of improved usefulness, economy of
time, chemicals and filters, with the further advantage of certainty in filtration.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said John Sheddens Campbell in the Great Seal Patent Office on the
24th January 1878.
JOHN SHEDDENS CAMPBELL, at present residing in the Town and County of
Sligo, Ireland. "A NEW OR IMPROVED FABRIC OR FILTER FOR FILTERING
CHEMICALS OR LIQUID SUBSTANCES." A communication from abroad by Thomas
Ross, of Cape Town, Cape of Good Hope.
My said Invention relates to improvements in "filters" or fabric to be used for
filtering chemicals or substances of a liquid, viscid, or albuminous nature, such as
nitrate of silver, varnish, or albumen.
The filter at present in use is made of either white or grey bibulous paper of a
porous nature, which being folded and placed inside of a glass or porcelain funnel or
filler, allows the chemical poured into it to be filtered through it.
But when the chemical is poured in, and the filter paper made thoroughly wet,
the line of the filter coincides so exactly with that of the funnel or filler all over the
whole surface, except the extreme apex, filtration is rendered inconveniently slow,
owing to the clinging of the wet filter to the sides of the funnel; and further, owing
to the soft porous nature of the filter paper, great care has to be taken to prevent
the filter paper from breaking, which, with every care, frequently happens, thus
causing a waste of liquid and a great waste of time, owing to the necessity of
filtering the chemicals over again.
To remedy these obviate defects is the principal object of this Invention, which
consists as follows:-Any ordinary filter paper, such as is now in use, being found
the most suitable material, to one side of this filter paper is cemented or otherwise
fixed a piece of netting, inuslin, or any other such like material of an open texture,
sufficient to allow the liquids to pass freely through.
The netting or muslin is made to adhere by means of some substance, such as
albumen or gum, which will not injure the chemicals to be filtered, although other
adhesive substance may be used, according to the nature of the chemicals to be
filtered; or when a chemically pure filter is required, the netting or muslin may be
made to adhere to the paper by pressure, only without the use of any adhesive
matter; or under another modification, the two fabrics may be joined together round
the edge only by sewing, or by gum or other adhesive substance, and in this way
the main body or filtering part of the fabrics, being above the level of the liquid,
would be absolutely free from any impurities which would injure the chemicals
being filtered.
To fix the muslin to the paper, after being coated with the albumen or cementing
substance, either the one or the other is wetted or damped, and when laid together
a hot iron may be passed over them to coagulate the albumen, and also to bring the
netting or muslin in close contact with the paper.
Instead of pressing the netting or muslin to the bibulous filter paper by hot
irons, they may be fed in, either in pieces or in a web form, between hot rollers,
so as to make them adhere and dry the albumen or other cementing substance
at the same time, and by another improvement these rollers might be fluted so as
to give a fluted or corded surface or effect to the fabric, which would further assist
filtration by exposing a larger filtering surface in the same diameter, increase its
strength, and assist in keeping the filtering material off the supporting surface of the
funnel or filler in the same manner as the plain muslin or netting does in the former
modification.
The advantages of these improvements will be obvious, as the netting or muslin
strengthens the filter so that it cannot break by ordinary use, and prevents adhesion
of the filter to the sides of the funnel or filler, thus allowing the chemicals to pass
freely through over the whole surface of the filter; another important advantage
being, that the same filter may be used over again frequently, which thus gives by
this Invention a certainty and security of filtration not hitherto obtained. And

page_text: liquids of a viscid or glutinous nature, such as albumen, varnish, or gelatine, may be
filtered freely by these improvements, which could with difficulty be filtered at all
by the filtering material previously in use.
The Invention thus combines the qualities of improved usefulness, economy of
time, chemicals, and filters, with the further advantage of certainty in filtration.
This filter will also be found to serve the purpose for
"
frame" filtering which is
at present usually done through a cloth stretched across a wooden frame.
Having now described the nature of my said Invention, and the manner of per-
forming the same, I have to state that I do not confine myself to the precise details
herein described or delineated, but what I consider novel and original, and therefore
claim as the Invention secured to me by the herein-before in part recited Letters
Patent is, the manufacture and use of chemical filters composed of a combination of
filter paper, with a layer of muslin or netting, all substantially as and for the
purposes herein described, or any mere modification thereof.
In witness whereof, I, the said John Sheddens Campbell, have hereunto set my
hand and seal, this Twenty-second day of January, in the year of our Lord
One thousand eight hundred and seventy-eight.