A CERTAIN IMPROVEMENT OR IMPROVEMENTS IN THE MANUFACTURE OF WIN- DOW GLASS, OF THE KIND OR DESCRIPTION COMMONLY WROUGHT OR FABRICATED INTO CROWN GLASS OR GERMAN SHEET GLASS, AND ALSO IN A CERTAIN PROCESS OR PRO- CESSES IN THE MANUFACTURE OF CROWN GLASS
Year: 1817

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CHARLES
ATTWOOD, of Bridge Street, Blackfriars, in the City of London, Window
Glass Manufacturer, send greeting.
WHEREAS His most Excellent Majesty King George the Third, by His
Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Fifth day of August,
in the fifty-seventh year of His reign, did give and grant unto me, the said
Charles Attwood, my executors, administrators, and assigns, His special
licence, full power, sole privilege and authority, that I, the said Charles Att-
wood, my executors, administrators, and assigns, during the term of years
therein expressed, should and lawfully might make, usc, exercise, and vend,
within England, Wales, and the Town of Berwick-upon-Tweed, my Invention
of "A CERTAIN IMPROVEMENT OR IMPROVEMENTS IN THE MANUFACTURE OF WIN-
DOW GLASS, OF THE KIND OR DESCRIPTION COMMONLY WROUGHT OR FABRICATED INTO
CROWN GLASS OR GERMAN SHEET GLASS, AND ALSO IN A CERTAIN PROCESS OR PRO-
CESSES IN THE MANUFACTURE OF CROWN GLASS;" in which Letters Patent
there is contained a proviso obliging me, the said Charles Attwood, under
my hand and seal, to cause a particular description of the nature of my said
Invention, and the manner in which the same is to be performed, to be
inrolled in His Majesty's High Court of Chancery within two calendar
months next and immediately after the date of the said in part recited
Letters Patent, as in and by the same (relation being thereunto had) may
more fully and at large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I do declare
the nature of such part of my Invention or improvement or improvements
as applies to the manufacture of window glass of the kind or description
commonly wrought or fabricated into crown glass or German sheet glass, to
consist in the use or employment in the manufacture thereof of the lixiviated
ashes, or earthy or insoluble, or partially and in great degree insoluble, residue
of kelp or barilla respectively, or both of them, either combined with kelp or
barilla, or other alkali or saline matters or otherwise, or of any or all of such
ingredients combined with lime or calcareous earth or otherwise; and after the
alkaline and saline matter originally contained in such kelp or barilla hath
been extracted, or in a very great degree extracted, by water or otherwise by
or for or for the use of persons using or requiring such alkaline and saline
matter, or some part thereof, for the manufacture of soap or otherwise, in lieu
of using or employing therein such kelp or barilla respectively, or both of
them, either singly or combined with lime, or together and combined with
lime or otherwise, according to any mode heretofore or at present in use, and
that such lixiviated ashes or insoluble residue of kelp and barilla respectively.
as aforesaid, may be used either singly or combined with each other in different
and any proportions, and combined either singly or together with different
alkaline or saline matters, as aforesaid, in certain very variable proportions, or
combined therewith, or otherwise and more or less sparingly, with lime or
calcareous earth. And for the more perfect and certain understanding of
such part of my said Invention as consists herein, I do declare the proportions
in which I do use the aforesaid ingredients, and the manner of performing the
same, to be as follows (that is to say) :-
I do take eight hundredweight and one quarter of the ashes of kelp or
barilla, or of kelp and barilla combined together in any proportions, and lixi-
viated as aforesaid, and I do grind and sift them, and afterwards mix them
with ten hundredweight and one half of sand or other silicious matter proper
for the manufacture of that kind or description of glass in question, and pre-
viously calcined, and I do calcine the whole together into a frit; and I
do employ such frit as my material to be manufactured into glass, combined
with any such kind or proportion of cullet or old or broken or waste glass,
as may be conveniently employed in the manufacture of glass of the same
description under any improved method or system heretofore or at present in
use; and I do employ the same methods and rules in the grinding and sifting
and calcining of the said materials, and in the making of the same into glass,
as are at present employed and in use, or may be advantageously employed
or used, with regard to any materials at present or heretofore employed

page_text: therein. And I do further declare that kelp or barilla or other alkaline or
saline matters, in any state proper to be employed in the manufacture of glass
of the same kind or description, may be advantageously and must sometimes
necessarily be added to the materials heretofore described as employed by me
therein, and that they may consist either of alkaline and saline matter left in
or not thoroughly extracted from the lixivated ashes as aforesaid, or of such
matter subsequently added thereto, or to the other ingredients generally, or to
any of them, and either calcined therewith or with some or any of them, or
otherwise as may be convenient or useful, and that the addition or retention
of such alkaline or saline matter as aforesaid is serviceable and useful in
quickening the operation of fusing or melting the materials, and is in some
cases necessary, tho' not in all, on account of the difference in the quality or
component parts of such lixivated ashes, and to prevent or diminish a great
number of opake grains of lumps or knobs of different sizes commonly called
ambittiness, or a general milky or cloudy appearance in the body of the glass
which the earthy parts of certain kinds of kelp or barilla uncombined with
such matter, and perhaps in general have in a degree a tendency to produce.
And further, I do declare that I have found the addition of the chrystalised
carbonate of soda in proper proportions to the other materials according to the
circumstances, a very convenient and effectual mode of administering such
addition of alkaline or saline matter as aforesaid, but that no proportion
proper or convenient in all cases can be laid down, though it may be easily
ascertained and adjusted by any intelligent manufacturer on the occurrence of
the occasions requiring it. And further, I do declare that in the preference
of any mode of administering such addition of alkaline or saline matter to the
other materials, or of such retention thereof therein, the manufacturer will be
better guided by his own observation and experience, and by attention to the
variations in the costs or charges of the different articles and modes, than by
any rate or rule which may be given for that purpose. And I do further
declare that a certain proportion of lime of a kind and in a state proper for
glass making may be added to or substituted for part of the ashes before
mentioned, or that such ashes of kelp and barilla lixiviated as aforesaid may
be combined with a moderate proportion of, or that a part of them may be
replaced by, an equal or nearly equal part of such ashes lixiviated by the
soap makers, and combined, during the process of such lixiviation according
to the system at present.commonly in use amongst them, with lime in certain
somewhat variable proportions, and that such addition or substitution of lime,
or of such ashes combined with lime, will quicken the operation of melting or

page_text: fusing the materials, but that I do not recommend the use of such lime, or of
such ashes combined with lime, except in very sparing proportions; that is to
say, I do recommend that not more than one half an hundredweight of such
lime be added to or substituted for an equal or nearly equal part of the afore-
mentioned quantity of eight hundredweight and one quarter of lixiviated
ashes, and that not more than one hundredweight of ashes lixiviated by the
soap makers, and combined with lime as afore-mentioned, be used with the
same or substituted for an equal or any other part thereof. And I do further
declare, that for every such quantity of lime so added or combined with the
other materials, as before said, a greater necessity or occasion exists for the
addition or retention of alkaline or saline matters, as aforesaid, or for the
employment of a larger quantity thereof, and that the employment of such
lime, though practicable in larger proportions in combination with such alkaline
and saline matter, will be found in such case generally ineconomical and
hazardous. And I do further declare that by reason of the great difference in
the quantities and natures of the materials I do employ, that no proportions can
be stated which would prove in all cases the best and most economical, but
that those which I have stated will be found to come as near as may be
thereto. And further, that the addition or retention of such alkaline or saline
matter, as before mentioned, will be frequently necessary, and that the manu-
facturer must be guided therein by his own experience of the materials; and
generally, I do state for his guidance, that it will rarely happen that the uso
of the lixiviated ashes in the proportion of eight hundredweight and one
quarter, or thereabouts, whether or not combined with lime or soap makers"
residue, containing lime as aforesaid, to ten hundredweight and an half of
sand or silicious matter, will require more alkaline or saline matter than
is contained in or generally equivalent in glass making to four hundred-
weight of crystallized carbonate of soda containing only twenty per cent. of
alkali or thereabouts, and that he will find no difficulty in ascertaining by
experience the quantity of saline or alkaline matter proper to be retained or
added in any other shape as equivalent in its effects thereto.
And further, with regard to that part of my Invention or improvement or
improvements which relate to a certain process or processes in the manufacture
of crown glass, I do declare the same to consist in contrivances or methods of
operation for preventing or lessening the arching, crooking, or curvature of the
table of glass which takes place commonly, if not always, under the mode or
modes of operation at present or heretofore in use before such table bath
been carried or conveyed, and sometimes in part while it is being carried or

page_text: conveyed into the annealing arch or kiln, and in contrivances or methods. of
operation for preventing or lessening a further arching, crooking, or curvature
of such table, which takes place commonly, if not always, in the said annealing
arch or kiln.
And I do declare the former part of such part of my said Invention or
improvement or improvements to be effected, or capable of being effected,
either by applying a proper support to such table during the time of its being
laid down and remaining in an horizontal position, or by avoiding laying it
down altogether and detaching the punty or pontil, as it is sometimes called,
while the table remains in a perpendicular position resting on its edge in or
against an apparatus properly contrived for its support.
And I do declare the second part of such part of my said Invention or
improvement or improvements to consist in the suspending the tables of glass
perpendicularly in the annealing arch or kiln in a proper metallic apparatus
or framework at such a distance from each other as to prevent lateral pressure,
and the apparatus or framework contrived with proper joints, hinges, or
links, or combined with chains in such a manner as to preserve, by
the operation of its own weight and that of the glass, a position perfectly
perpendicular.
And I do further declare that the modes of effecting or performing these
operations, and the apparatus required therein, are so simple and easy as that
no particular description thereof is necessary, but that they may be done and
performed by any tolerably skilful workman by a great variety of ways, differ-
ing from each other in their minute detail more than in their principle or
effect, and containing little other difficulty in their practice than arises from
the inaptitude of many workmen to change their habits, though but in a
trifling degree. And I do further declare that I am not aware of any other
particular direction to give therein, than that it is necessary that the whole of
the apparatus which comes at any time in contact with the glass should
be kept at a proper temperature, that is to say, not materially below that of
the glass itself.
In witness whereof, I, the said Charles Attwood, have hereunto set my
hand and seal, this Fourth day of October, in the year of our Lord
One thousand eight hundred and seventeen.
CHARLES (L.s.) ATTWOOD.
CHARLES (L.s.) ATTWOOD.

page_text: AND BE IT REMEMBERED, that on the Fourth day of October, in the
fifty-seventh year of the reign of His Majesty King George the Third,
the said Charles Attwood came before our said Lord the King in His
Chancery, and acknowledged the Instrument aforesaid, and all and every
thing therein.contained and specified, in form above written. And also the
Instrument aforesaid was stamped according to the tenor of the Statute made
in the fifty-fifth year of His said Majesty's reign.
Inrolled the Fourth day of October, One- thousand eight hundred and