IMPROVEMENTS IN THE MANUFACTURE OF THE PREPARATIONS CALLED GELATINE, SIZE, AND GLUE
Year: 1838

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
RATTRAY, of Aberdeen, North Britain, Chemist, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Letters Patent under the Great Seal of Great Britain, bearing date at London,
the Thirty-first day of May last, did, for Herself, Her heirs and successors,
give and grant unto me, the said William Rattray, Her especial licence,
full power, sole privilege and authority, that I, the said William Rattray, my
exors, adñiors, and assigns, or such others as I, the said William Rattray, my
exors, admors, 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, usé, exercise, and vend, within that part of
the United Kingdom of Great Britain and Ireland called England, my
Invention of "IMPROVEMENTS IN THE MANUFACTURE OF THE PREPARATIONS CALLED
GELATINE, SIZE, AND GLUE;" in which said Letters Patent is contained a
proviso that I, the said William Rattray, shall cause a párticular description
of the nature of my said. Invention, and in what manner the śámé is to be
performed, to be enrolled 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.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
William Rattray, do hereby describe the nature of my said Invention as
follows, that is to say:-
Of the animal substances usually employed in the manufacture of gelatine,
size, and glue, I prefer the limed hide pieces or roundings commonly called
scrows or scrolls, also called glue pieces; but my Invention, hereafter
described, is applicable to other animal substances, such as fleshings, bate
shavings, and like animal matter, from which gelatine is extracted. In the
following description, therefore, of my Inventlon, the word scrow is used
indiscriminately to designate whatever animal substance may be employed.
The following is a description of the mode or process in which I perform my
Invention:-
The serows used are to be put into a vat or vessel and covered with cold
water, and allowed to steep therein for some days until they become putrescent.
The scrows having become putrescent are to be then well washed in pure
water with stampers. These stampers should be applied with considerable
force, by which means the cleansing of the scrows is better effected, and there
should be a constant supply of the pure water, and the washing should be
carried on with it until the scrows are so thoroughly washed that the water in
which they are being cleansed should run off clear. Bate shavings, fleshings,
and other inferior scrows generally require much more washing than others.
The scrows, when thus thoroughly washed, are to undergo the operation next
described, which is done as follows:-I take a portion of water impregnated
with sulphurous acid; such water so impregnated I prefer to be of a strength
indicated by six degrees of Twaddle's hydrometer (an hydrometer well known
as a means of ascertaining the specific gravity of liquids), and I put the same
into any convenient stone, earthenware, wooden, or leaden vessel, upon which
the above-mentioned liquid has not a prejudicial effect, and dilute it with cold
water. Into this diluted liquid I put the washed scrows, care being taken to
add as much cold water as will cover the scrows completely. The vessel thus
charged is to be furnished with a close cover, which should be kept on during
the immersion, and the vessel should be left in this state until the acid has
had sufficient time to act upon the scrows, which is generally effected in from
twelve to twenty-four hours, time having been allowed for the acid to act upon
the scrows; I then run the waste liquor off. I now wash the scrows which
have been thus partially prepared thoroughly by means of stampers in pure
cold water, the stampers being used with force, as before mentioned. After
being thus washed the immersion of the scrows in a closed vessel, again filled up

page_text: with water added to a like proportion, as after mentioned, of the said impreg-
nated liquid, is to be repeated as above described; and after the scrows have
remained a second time in steep, say from twelve to twenty-four hours, the vessel
is to be uncovered, when the waste liquor will generally be found still to retain
a considerable smell of sulphurous acid. When this smell is not apparent the
waste liquor should be again run off, and the scrows be again washed with
stampers in cold water and then again immersed from twelve to twenty-four
hours in diluted liquor, as above mentioned. If the waste liquor should now
retain a considerable smell of sulphurous acid the use or application of
the said impregnated liquid will not be further necessary; but if the waste
liquor should not after this third immersion of the scrows have a decided sul-
phurous smell, the operation of immersion as above described must be re-
peated until it is found that the sulphurous smell exists to a considerable
extent in the waste liquor, which is the indication I have found to answer in
practice as informing me best that the scrows have been sufficiently acted
upon by the acid. It may be necessary here to observe that the quantity of
the impregnated liquid to be used on each immersion will vary very much
according to the nature of the scrows. Thus, scrows from young animals in
general require more, from old animals in general less, of the impregnated
liquid; so if the scrows be very putrescent they require more. I find that
taking limed glue or hide pieces, every hundredweight of scrows, weighed
previous to their first steeping in water, will require on the average twenty-
five pounds of the impregnated liquid of the strength above mentioned. Some
scrows, such as sheepskins, will be sufficiently acted upon with as little as
twenty pounds per hundredweight, or even less, for each immersion; others,
again, such as bate shavings or fleshings, may require as much as forty pounds
or more per hundredweight for each immersion; and experience alone will
enable the operator at the end of the first immersion to regulate the process,
but the state of the waste liquor as above described will furnish the best
criterion, and the quantity of the impregnated liquid may. be increased or
diminished at a subsequent immersion, according to the effect produced by the
preceding one. The scrows having been now, in the opinion of the operator,
sufficiently acted upon by the acid, the waste liquor in which they nave finally
been steeped is to be drawn off, and the scrows are to be again well washed
by means of stampers in cold water. More than two applications of the
impregnated liquid are chiefly necessary for those scrows which contain a
larger quantity of lime, or carbonate of lime, or phosphate of lime. The
scrows having been so finally washed as lastly described, I place them in a

page_text: water-tight vessel of wood, pure hot water, the temperature of which should
be about one hundred and fifty degrees of Fahrenheit, is then to be allowed to
run or to be poured into the said last-mentioned vessel in sufficient quantity
to cover the scrows, and should immediately afterwards be run off. The vessel
is then filled a second time with hot water at a like temperature, and it will be
found, on applying a thermometer to the water at the top of the vessel, that it
is of the temperature of about one hundred and twenty-five degrees Fahrenheit,
which is the temperature I recommend and endeavour to obtain. The vessel is
to be then covered and the water prevented from cooling materially below this
temperature. The mode I adopt for this purpose is by having the vessel placed
in a chamber heated by flues, the temperature of which chamber is kept up to
about one hundred degrees of Fahrenheit. At the expiration of about twenty-
four hours a gelatinous solution has been formed, and should be run off and
passed through several folds of woollen cloth, or other suitable filtering material.
This solution is the substance or preparation known as gelatine or jelly size ;
but I proceed to procure further gelatinous solutions from the scrows in the said
last-mentioned vessel by the means next mentioned. I pour on the same
scrows more hot water of such a temperature as will leave the temperature of
the scrows, when they are entirely immersed, at about one hundred and thirty
degrees Fahrenheit. The scrows being left in this state for about twenty-four
hours, a gelatinous solution is again formed, which I run off and filter in like
manner as before mentioned regarding the said first-mentioned gelatinous
solution. I then again pour more hot water on the remaining scrows in the
vessel of a temperature sufficient to cause the temperature of the scrows and
water in the vessel to be about one hundred and forty degrees of Fahrenheit;
and the scrows being again left in this hot water for twenty-four hours, a
further gelatinous solution is formed, which is run off and filtered in like
manner as before mentioned regarding the said first-mentioned gelatinous
solution. I then twice more, seriatim, add hot water to the scrows, of the tem-
perature of about one hundred and eighty degrees Fahrenheit, and after leaving
the scrows each time in this hot water for about twenty-four hours, I run off
the gelatinous solution which has been formed and filter the same in manner
herein-before described. In order to keep the temperature of the scrows
during their respective treatments as above described at nearly one hundred
and thirty degrees, one hundred and forty, and one hundred and eighty degrees
of Fahrenheit respectively, during the whole of each of the respective
periods of twenty-fours hours of immersion I keep up the heat of the chamber
aforesaid in which the vessel is placed, and regulate the heat of the same so

page_text: as to maintain the above temperatures respectively in the scrows. After
running off the gelatinous solution formed from the said second saturation or
immersion of the scrows in hot water of the temperature of one hundred and
eighty degrees of Fahrenheit, I add more water to the scrows in the vessel
and cause the same to boil by means of introducing into the same a pipe kept
charged with steam. This boiling is continued for about four hours, when the
gelatinous solution is drawn off and filtered, and again hot water is added,
and the scrows further boiled for about four hours more, and the gelatinous
solution run off and filtered; the remaining contents of the vessel are then
thrown away.
All these gelatinous solutions so procured as herein-before described form,
on cooling, gelatine or jelly size, and the same may, by evaporation, as now
usually practised for making gelatinous solutions into glue, be formed into
glue. If it be intended to use the gelatinous solution for alimentary or nu-
tritious purposes, the scrows, just before hot water is added as before described,
may be immersed for about fifteen minutes in a weak solution of chloride of
lime, or in water impregnated with chlorine.
Now I do not claim any of the vats, vessels, or utensils above mentioned;
nor do I claim the washing of the scrows with stampers; nor do I claim the
application of the particular temperature which I have described as used by
me in extracting the jelly; nor do I claim the manufacture of gelatine, size,
and glue from scrows, nor the use of the same scrows in a putrified state for
making the said preparations; but I do claim the use or application of sul-
phurous acid in the manner above described, or in any similar manner, to the
scrows previous to the jelly being extracted therefrom, for the purposes of the
manufacture of the preparations called gelatine, size, and glue.
Although I have, in the above Specification, described that mode only of
applying the sulphurous acid which I have found most convenient in practice,
yet obviously the same may be applied directly to the water in which the
scrows are to be steeped or are being steeped; but I find the method I have
described to be the most convenient and economical; and having thus
described the nature of my Invention, I declare this to be a true Specification
thereof.
In witness whereof, I, the said William Rattray, have hereunto set my
hand and seal, this Seventeenth day of October, in the year of our
WILLIAM (L.S.) RATTRAY.

page_text: AND BE IT REMEMBERED, that on the Eighteenth day of October, in
the year of our Lord 1888, the aforesaid William Rattray 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
above written. And also the Specification aforesaid was stamped according
to the tenor of the Statute made for that purpose.
Inrolled the Twenty-ninth day of November, in the year of our Lord
One thousand eight hundred and thirty-eight.