AN IMPROVED FILTERING MEDIUM
Year: 1872

page_text: LETTERS PATENT to Frederick Ludewig Hahn Danchell, of Horwich,
in the County of Lancaster, Civil Engineer, for the Invention of
"AN IMPROVED FILTERING MEDIUM."
Scaled the 25th June 1872, and dated the 7th May 1872.
PROVISIONAL SPECIFICATION left by the said Frederick Ludewig
Hahn Danchell at the Office of the Commissioners of. Patents, with
his Petition, on the 7th May 1872.
I, FREDERICK LUDEWIG HAHN DANCHELL, of Horwich, in the
County of Lancaster, Civil Engineer, do hereby declare the nature of
the said Invention for "AN IMPROVED FILTERING MEDIUM," to be as
follows:-
This Invention consists in a homogeneous combination of carbonation
matter with certain mineral matter.
The substances which I use to serve as the carbonatious compound
are animal or vegetable matter more or less decayed, such as leaves,
grass, mosses, water plants, seaweeds, and other plants; also vegetable
or animal refuse from stables, houses, or manufactories, and sewage
matter generally.

page_text: The substances preferred as the mineral constituent are loam, clay,
carbonate, sulphate, phosphate of lime, or a combination of one or more
of them.
These respective substances are then intimately mixed, dryed, and
charred.
The proportions of the carbonatious and mineral substances are such
that the first should constitute from 10 to 15% of the whole after
charring, and the mineral the rest.
The mixing process is carried out by means of edge rollers or other
machinery which will ensure an intimate combination.
The charring is carried on in retorts or any other of the well-known
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Frederick Ludewig Hahn Danchell in the Great
Seal Patent Office on the 7th November 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, FREDERICK
LUDEWIG HAHN DANCHELL, of Horwich, in the County of Lancaster,
Oivil Engineer, send greeting.
:
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Seventh day of May, in the year of
our Lord One. thousand eight hundred and seventy-two, in the thirty-
fifth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said Frederick Ludewig Hahn Danchell, Her
special licence that I, the said Frederick Ludewig Hahn Danchell, my
executors, administrators, and assigns, or such others as I, the said
Frederick Ludewig Hahn Danchell, my executors, administrators, and
assigns, should at any time agree with, and no others, from time to
time and at all times thereafter during the term therein expressed,
should and lawfully might make, use, exercise, and vend, within the
United Kingdom of Great Britain and Ireland, the Channel Islands,
and Isle of Man, an Invention for "AN IMPROVED FILTERING MEDIUM,"
upon the condition (amongst others) that I, the said Frederick Ludewig
Hahn Danchell, my executors or administrators, by an instrument in
writing under my, or their, or one of their hands and seals, should
°

page_text: "
particularly describe and ascertain the nature of the said Invention,
and in what manner the same was to be performed, and cause the same
to be filed in the Great Seal Patent Office within six calendar months
next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Frederick Ludewig Hahn Danchell,
do hereby declare the nature of my said Invention, and in what manner
the same is to be performed, to be particularly described and ascer-
tained in and by the following statement, that is to say :—
י
My Invention of an improved filtering medium consists of a homo-
geneous combination of certain carbonaceous and mineral matters.
را
The carbonaceous substance which I use is peat or vegetable matter
more or less decayed, such as leaves, grass, moss, water plants, and sea-
weed, such decayed matter being found in greatest abundance in peat
bogs, marshes, and similar localities. I also use decayed or partially
decayed vegetable or animal refuse from stables, manufactories, and
houses, and especially the more solid portions of general sewage
matter.
The substances which I prefer to use as the mineral constituents,
although I do not confine myself to their use, are any suitable form of
alumina, as loam, clay, phosphate of alumina, or even alumina itself,
also lime or carbonate of lime, or phosphate of lime, or any suitable
combination of them, or any of them.
These or any such suitable vegetable and mineral substances or
ingredients are intimately mixed and macerated together in a moist
condition so as to form a partly homogeneous mass, the macerating and
mixing together being performed in a machine similar to a mortar mill;
or by means of edge rollers, or in any other convenient manner.
'When the mixing is sufficiently effected the pasty material obtained
is dried by exposure to the atmosphere or by artificial appliances,
and then charred either in retorts or in furnaces, as in the ordinary
manufacture of charcoal.
0
As the material becomes charred it is withdrawn from the retorts or
other apparatus and broken up into small fragments, when it will be
ready for use for the purposes of filtration.
In all cases in which the material is required for filtering potable
water, sugar solution, or for purifying any edible or potable substance, I
use the peat or the partially decayed vegetable matter found in peat

page_text: ,bogs on account of its freedom from offensive impurities. But when
the object is simply the disinfection of sewage water I then avail. myself
.of
any suitable decayed vegetable or animal refuse such as already
described that can bo most conveniently obtained, and for this latter
purpose I especially use the carbonaceous refuse of the sewage itself.
The proportion of carbonaceous to mineral matter should be such that
-the carbonaceous matter may constitute from 10 to 15 per cent. of the
whole material when charred. But the proportions may be considerably
varied according to the quality or nature of the mineral ingredient, and
the purpose to which the filtering material is to be applied.
Having thus described the nature of my Invention, and the manner
of carrying it into effect, I declare that what I claim is, the production
of an improved filtering medium by mixing together and then charring
the mixture so made of peat, vegetable matter more or less decayed,
such as contained in peat bogs, marshes, and similar localities, or the
carbonaceous refuse of nightsoil or sewage decayed or partially decayed,
and suitable mineral substance in the manner and for the purpose
herein-before described.
.
any
In witness whereof, I, the said Frederick Ludewig Hahn Danchell,
have hereunto set my hand and seal, this Seventh day of
November, in the year of our Lord One thousand eight hundred
and seventy-two.
F. L. HAHN DANCHELL. ¯ (L.S.)
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