IMPROVEMENTS IN PRESERVING FOOD
Year: 1872

page_text: LETTERS PATENT to William Glen Walker, of Helensburgh, in the
County of Dumbarton, North Britain, for the Invention of
"IMPROVEMENTS IN PRESERVING FOOD."
Sealed the 26th July 1872, and dated the 29th January 1872.
PROVISIONAL SPECIFICATION left by the said William Glen Walker
at the Office of the Commissioners of Patents, with his Petition,
on the 29th January 1872.
I, WILLIAM GLEN WALKER, of Helensburgh, in the County of
Dumbarton, North Britain, do hereby declare the nature of the said
Invention of "IMPROVEMENTS IN PRESERVING FOOD," to be as follows, that is
to say :-
This Invention relates to the preservation of animal food by refrigera-
tion on shipboard or in stores, and has for its object the economising of
cooling effect. It consists as follows:-The compartments in which the
food to be preserved is placed are surrounded by non-conducting or
insulating material, the outer air being
er air being excluded by any of the ordinary
means employed in the construction of ice stores, 'so that the contents

page_text: when refrigerated can absorb heat from without only to a minimum
extent, the only heat conductors between the outside and inside of these
insulated chambers being the gearing or shafting necessary to convey
power to drive the internal refrigerating mechanism and the piping
necessary for the ingress and egress of water, and these pass through
stuffing boxes to prevent the passage of air. The air pumps or fanners
for the circulating and refrigerating machinery for cooling of air (and
which may be any of the well-known refrigerating machines) are placed
within one or more of the insulated compartments, and the food to be
preserved is likewise placed within the same set of compartments.
The mechanism inside is driven by power from without, communicated
by the gearing referred to, and the internal air is circulated by the means
also referred to, the internal heat concentrated by the machinery placed
inside for the purpose being absorbed by water introduced by the ingress
pipe, and then removed from the insulated chambers by the egress pipe
provided for that purpose.
The temperature of the compartments is reduced to and kept below the
freezing point, so that after a time maximum of cold is reached, and the
refrigerating machinery may then remain unused until heat has again
gradually penetrated the compartments and raised their temperature to
above the freezing point. To facilitate the reduction of temperature by
removal of moisture from and to purify the air it is during its circulation
brought in contact with one or more of the various known materials
used for such purposes.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Glen Walker in the Great Seal Patent
Office on the 26th July 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
GLEN WALKER, of Helensburgh, in the County of Dumbarton, North
Britain, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-ninth day of January, in the
year of our Lord One thousand eight hundred and seventy-two, in the

page_text: .
thirty-fifth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said William Glen Walker,
Her special licence that I, the said William Glen Walker, my
executors, administrators, and assigns, or such others as I, the said
William Glen Walker, 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 "IMPROVEMENTS IN PRESERVING
FOOD," upon the condition (amongst others) that I, the said William
Glen Walker, my executors or administrators, by an instrument in
writing under my, or their, or one of their hands and seals, should
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 William Glen Walker, do hereby
declare the nature of my said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and by
the following statement :-
My said Invention relates to the preservation of animal food by
refrigeration on shipboard or in stores, and has for its object the
economising of cooling effect in connection with preserving food, and
consists all as follows:-The compartments, in which the food to be
preserved is placed, are surrounded by non-conducting or insulating
material, the outer air being excluded by any of the ordinary means
employed in the construction of ice stores, so that the contents when
refrigerated can absorb caloric from without only to a minimum extent,
the only heat conductors between the outside and inside of these insulated
chambers being the gearing or shafting necessary to convey power to
drive the internal refrigerating mechanism and the piping necessary for
the ingress and egress of water, and these pass through insulated stuffing
boxes to prevent the passage of air. The air pumps or fanners for
circulating and refrigerating machinery for cooling the refrigerating
air (and which may be any of the well-known refrigerating machines)
are placed within one or more of the insulated compartments, by

page_text: .
preference near the centre of the others, within which the food to be
preserved is likewise placed, the machinery and the food being within
the same set of compartments.
The mechanism inside the compartments is driven by power from
without, communicated by the gearing referred to, and the internal air
is circulated by the means also referred to, the internal caloric con-
centrated by the machinery placed inside for the purpose being absorbed
by water introduced by the ingress pipe and then removed with it
from the insulated chambers by the egress or discharge pipe, both
provided for that purpose.
The temperature of the compartments is reduced to and kept below
the freezing point, so that after a time, as latent heat gets overcome,
what may be termed a stock of cold at temperature sufficiently reduced
for food preserving, gets stored or bottled up, and the refrigerating
machinery then may remain unused until caloric again has gradually
penetrated the compartments and increased their temperature to a point
above the freezing point, and to facilitate the reduction of the tem-
perature of the air and the removal of all moisture and impurities
therefrom, the air is during its circulation brought into contact, with
one or more of the various known materials used for such purposes.
And in order that my said Invention and the manner of performing
the same may be properly understood, I shall now proceed to describe
what I at present believe to be the best modes and means of carrying
the same into effect or practice, the object of my said Invention being so
to preserve food by artificial cold that its utmost preservative power be
utilized, and so that the continuous use of heat withdrawing machinery
may be dispensed with, and so that the food can be transported either
without requiring that heat withdrawing appliances or machinery should
be transported along with it, or by carrying with it only such as but for
my Invention would be of inadequate power.
And the nature and novelty of performing my said Invention consist
as follows:-The stores, holds of vessels, railroad cars, or parts of them,
in which it is proposed to preserve or to preserve and transport food,
are surrounded with good non-conducting material, and otherwise are
arranged similarly to good ice stores or safes, the outside heat and air
being well excluded. The spaces thus insulated are divided into com-
partments, each so communicating by apertures with the others that air

page_text: can freely circulate. These apertures can be opened or shut by hand
rods from one of the compartments, hereafter described as a refrigerating
compartment, so that the circulation of air through a refrigerating com-
partment and one or more of the food compartments can be controlled
-
as desired.
I place in one of the compartments, and which I have referred to and
will hereafter refer to as a refrigerating compartment, any of the well-
known machines for withdrawing heat, preferably of that class which
withdraw heat by the alternate evaporation and condensation of a gas,
by preference likewise the machinery should be in duplicate and placed
within a central compartment. And the water necessary to absorb the
heat which such machinery will concentrate is forced through piping
into and from the refrigerating compartment. And the refrigerating
machinery is constructed to expose large cooling surfaces, which are
cooled by containing the evaporated gas or a liquor cooled by it to low
temperatures, preferably from fifteen degrees (15°) to twenty-five (25°)
degrees Fahrenheit, and these surfaces are enclosed within an air-tight
chamber of the refrigerating compartment, and by means of air pumps
air is forced into this chamber until a pressure of from twenty (20) to
forty (40) pounds to the square inch is obtained, and the air heated by
this compression contacts in the chamber with these cooling surfaces,
which absorb a portion of its heat. The compressed air is then inter-
mittently allowed to escape through a side valve or opening in one end.
of a cylinder, a piston so working in the cylinder as at each stroke to
expose the valve or opening. And the size of the valve or opening and
the speed of the piston are arranged in relation to the compressing air
pumps, so that pressure inside the chamber will continue as 'desired.
And the air is contrived to expand and escape into the adjoining food
compartment. The power is communicated from without to drive this
internal machinery by means of shafting or by pistons and actuating
rods, which shafts or rods and the necessary piping for ingress and egress
of water pass into and from the compartment by suitable close stuffing
boxes or other tight-fitting equivalents to prevent the passage of air,
and have connections so that the point of their passage can, when not in
use, be as completely insulated as the other surroundings of the com-
partments, and the driving connections also may partially be insulated ;.
and the mechanic when within the compartment must be clad as for an
Arctic climate.

page_text: +
Instead of withdrawing heat by machinery as referred to where
during winter ice can at little cost be stored, there may be substituted
the contrivance of circulating within piping an uncongealable liquor
alternately through the compressed air chamber of the refrigerating
compartment, and through such a well-known freezing mixture as salt
and ice, the other arrangements being the same as when one or other of
the well-known heat withdrawing machines referred to are used. And
charcoal and common salt are placed at each aperture, and until the
temperature is below the freezing point a more powerful deliquescent
may be used, and a respirator may also be placed so that air in its
circuit must freely contact or pass through them, and so get freed of
impurity and moisture. And ordinary blast fans or other blowing
apparatus may be used to assist the compressing air pumps in circulating
the air through the food compartments and back again to the refrigera-
ting compartment, and thus the circulation and refrigeration of the air
is continued through the food and refrigerating compartments so long as
required. And stores with refrigerating machinery may be used in con-
nection with ships or cars, the latter being placed alongside the stores,
so that the hold or part of it or the cars and contents can be refrigerated
by the machinery in the store, the circulation of refrigerated air from
the store to the ship or car, and again from the ship or car back to the
store, being forced through insulated windsails or other air conductors.
And similarly stores, ships, and cars can each be refrigerated from the
other. And to avoid rapid putrefaction of animal food after it has been
thawed it must not be refrigerated until about one hour after being
killed. And excepting for transit not exceeding two or three days when
first refrigerated it should be hung until rigid, and then it may be stored
with little regard to contact. And if milk be preserved it is first to be
frozen and then the temperature of its enclosure reduced to the extent
required, below thirty-two degrees (32°) Fahrenheit. Should a second
refrigeration of any food during transit be intended the stowage must be
so that the air can freely circulate, but if a second refrigeration. be un-
necessary this need not be considered. For transit, not exceeding three
weeks in tropical climates, or proportionally longer in colder climates,
in such refrigerating stores as have been described, food may be prepared
for shipment by being refrigerated in packages, which are to be sur-
rounded by good non-conducting material, or if the intended application
be only upon a small scale the alternative of reducing temperature by
enclosing the packages within a worm of piping, through. which an

page_text: uncongealable liquor is made to circulate, the worm being enclosed
within good non-conducting material can be substituted, and when the
temperature within the packages has been sufficiently reduced they can
be closed up, and the insulation of the packages from outside heat and
air then being completed the food will continue preserved, and thus can
be transported as ordinary merchandise. The degree to which tem-
perature should be reduced must depend upon the extent of surplus cold
requisite to be stored up, and which climatic conditions and the length
of transit intended must determine, but within large compartments, say,
each capable of containing one hundred tons of butcher meat, these
reasonably insulated and stored with meat, and outside temperature
averaging eighty degrees (80°) Fahrenheit in the shade, each degree
under thirty-two degrees (32°) will represent approximately but fully
one day's supply available for food preservation.
By the means described it is evident that a store may be made to
refrigerate the hold of a ship or a package in Norway or Canada to an
extent in excess of what is requisite for food preserving, so that the hold
of the ship or the package with such a surplus supply of cold can be
used to transport and to preserve the food which they contain until its
arrival in London, where another refrigerated store may receive it.
And for longer voyages, unless artificial refrigeration can be renewed at
ports of call, though it may be necessary to carry some refrigerating
machinery, it need be only of an auxiliary character and comparatively
of small power and bulk.
And having thus described the nature of my said Invention, and
the manner of performing the same, I wish it to be understood that
what I claim is,-
First. The modes and means of preserving food all substantially in the
new or improved manner herein distinguished and described.
Second. The placing of the refrigerating machinery for distributing
and producing artificial cold for preserving food within the same set
of insulated compartments as the food, and driving the said internal
machinery by power from without, the driving connections and the
piping being insulated and passing to the compartments, all substantially
5 in the new and improved manner herein described.
Third. Distributing artificial cold for preserving food by circulating

page_text: .
refrigerated air by contact under pressure with surfaces artificially
cooled to a lower degree than is possible by a stream of water.
Fourth. Transporting food within insulated spaces preserved by
artificial cold at temperatures below freezing point, produced in whole
or part by refrigerating mechanism or contrivances which are not
carried with the food, all substantially in the new or improved manner
herein described.
In witness whereof, I, the said William Glen Walker, have here-
unto set my hand and seal, this Twenty-second day of July, in
the year of our Lord One thousand eight hundred and seventy-
two.
Witness,
JOHN THOMSON,
Agent,
1
62, Buchanan Street,
Glasgow.
W. GLEN WALKER. (L.S.)