AN IMPROVEMENT IN --- DemonwAMION OR Å DRY TO OF FOOD 33 THE PRESERVATION OF ARTICL AR FOOD PROVISIONAL SPECIFICATION
Year: 1861

page_text: LETTERS PATENT to John McCall, of Houndsditch, in the City of London,
Provision Merchant, and Bevan George Sloper, of Walthamstow, in the
County of Essex, Chemist, for the Invention of "AN IMPROVEMENT IN
--- DemonwAMION OR Å DRY TO OF FOOD
33
THE PRESERVATION OF ARTICL
AR
FOOD
PROVISIONAL SPECIFICATION left by the said John McCall and Bevan
George Sloper at the Office of the Commissioners of Patents, with their
Petition, on the 24th October 1861.
We, JOHN MCCALL, of Houndsditch, in the City of London, Provision
Merchant, and BEVAN GEORGE SLOPER, of Walthamstow, in the County of
Essex, Chemist, do hereby declare the nature of the said Invention for
"AN IMPROVEMENT IN THE PRESERVATION OF ARTICLES OF FOOD," to be as
follows:-
In the preservation of meat and other articles of food it is usual to subject
them in tins to heat, in order to drive off air and oxygen contained in the
vessels, and in the meat or other articles of food themselves. For this purpose
an aperture is made in the tins, through which a portion of the air and oxygen
is driven off; and in order to drive off the whole, or as much as possible, it
has been necessary to use such an elevated temperature, or to apply heat for
so long a time as to injuriously affect the meat and food.

page_text: Our Invention consists in introducing into the tins some material or com-
position, for which oxygen has a greater affinity than for the meat or other
article of food under preservation, and which at the same time shall be in no
way detrimental to it. We have found in practice that sulphite of soda is the
best agent for our purpose; but we do not confine ourselves to the use of that
substance only. We encase or cover the sulphite of soda in gelatine, or other
suitable protecting coat to prevent its coming into action before the coat has
been dissolved by the heat to which the tin and contents are first subjected,
and the time of its solution we vary according to circumstances. About the
time we have calculated for its solution we hermetically seal the tin, and
then for a short period apply a higher degree of heat when the oxygen
remaining in the meat or other food will combine with the sulphite of soda.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John McCall and Bevan George Sloper in the Great Seal
Patent Office on the 24th April 1862.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, JOHN
MCCALL, of Houndsditch, in the City of London, Provision Merchant, and
BEVAN GEORGE SLOPER, of Walthamstow, in the County of Essex, Chemist,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-fourth day of October, in the year of our
Lord One thousand eight hundred and sixty-one, in the twenty-fifth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
us, the said John McCall and Bevan George Sloper, Her special licence that
we, the said John McCall and Bevan George Sloper, our executors, adminis-
trators, and assigns, or such others as we, the said John McCall and Bevan
George Sloper, our 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 IMPROVEMENT IN
THE PRESERVATION OF ARTICLES OF FOOD," upon the condition (amongst others)
that we, the said John McCall and Bevan George Sloper, or one of us, our
executors or administrators, by an instrument in writing under our, or their,
or one of our or their hands and seals, should particularly describe and ascer-
tain the nature of the said Invention, and in what manner the same was

page_text: 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 we, the said John McCall and Bevan George
Sloper, do hereby declare the nature of our 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 thereof, that is to say :-
In the preservation of meat and other articles of food it is usual to subject
them in tins to heat, in order to drive off air and oxygen contained in the
vessels, and in the meat or other articles of food themselves. For this purpose
an aperture is made in the tins through which a portion of the air and oxygen
is driven off. And in order to decompose the remaining portion of the air it
has been necessary to use such an elevated temperature, or to apply heat for
so long a time as to injuriously affect the meat and food.
Our Invention consists in introducing into the tins some material or com-
position for which oxygen has a greater affinity than for the meat or other
article of food under preservation, and which at the same time shall be in no
way detrimental to it. We have found in practice that sulphite of soda is the
best agent for our purpose; but we do not confine ourselves to the use of that
substance only. We prefer to encase or cover the sulphite of soda or other
suitable material or composition, as aforesaid, in gelatine or other suitable
protecting coat to prevent its coming into action before the coat has
been dissolved by the heat to which the tin and contents are first subjected,
and the time of its solution we vary according to circumstances. About the
time we have calculated for its solution we hermetically seal the tin, and then
for a short period apply a higher degree of heat, when the oxygen remaining
in the tin and in the meat or other food will combine with the sulphite of
soda. Instead of encasing the sulphite of soda or other suitable material or
composition, as aforesaid, in gelatine, we sometimes place it in a tin or other
suitable metal case having holes or perforations first made therein, and then
closed by a metal, which will become fused on being exposed to the higher
degree of heat, herein-before mentioned, after the outer tin case has been
hermetically closed. In some cases we simply introduce the sulphite of soda
or other suitable material or composition, as aforesaid, into the outer tin case
without first encasing or enclosing it; but, as before stated, we prefer to use
it enclosed in a case or cover.
And having now described the nature of our said Invention, and in what
manner the same is to be performed, we declare that we claim as our improve-
ment in the preservation of articles of food, the employment in and introduc-

page_text: tion into the cases containing the food to be preserved of some such agent as
sulphite of soda acting in manner and for the purpose herein-before described.
In witness whereof, we, the said John McCall and Bevan George Sloper,
have hereunto set our hands and seals, this Nineteenth day of April,
One thousand eight hundred and sixty-two.
JOHN MCCALL. (L.S:)
B. G. SLOPER. (L.S.)