IMPROVEMENTS IN PRESERVING AND ARRESTING DECAY IN CERTAIN VEGE- TABLE SUBSTANCES FOR THE PURPOSES OF FOOD AND MANURE
Year: 1868

page_text: LETTERS PATENT to James Dewar, Doctor of Medicine, in Kirkcaldy,
in the County of Fife, in North Britain, for the Invention of
"IMPROVEMENTS IN PRESERVING AND ARRESTING DECAY IN CERTAIN VEGE-
TABLE SUBSTANCES FOR THE PURPOSES OF FOOD AND MANURE."
Sealed the 14th August 1868, and dated the 6th June 1868.
PROVISIONAL SPECIFICATION left by the said James Dewar at
the Office of the Commissioners of Patents, with his Petition, on
the 6th June 1868.
I, JAMES DEWAR, Doctor of Medicine, in Kirkcaldy, in the County
of Fife, North Britain, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN PRESERVING AND ARRESTING DECAY IN CERTAIN VEGETABLE
SUBSTANCES FOR THE PURPOSES OF FOOD AND MANURE," to be as follows:-
The vegetable substances to which my Invention relates are grain
and marine vegetable substances. These substances are all subject to
fermentation and decay.
The object of my Invention is to arrest such decay when it has com-
menced and preserve the substance from further decay, as well as to
preserve the substance where decay has not commenced.

page_text: To effect this object I proceed as follows:-As respects grain, whether
it be wheat, oats, barley, or other grain, I subject it to the action of
sulphurous acid by immersing it in an aqueous solution of that acid, and
allowing it to steep therein for a period varying according to circum-
stances. So far as my present experience goes I prefer the immersion to
continue for about two hours. I then dry the grain thoroughly, and I
find that as respects grain in which decay has already commenced the
course of decay is arrested, the musty appearance arising from decay is
removed, and the grain is preserved from further decay for a long period
of time, fermentation being prevented by the action of the acid. Grain
in which decay has not commenced when treated with the acid, as above
mentioned, remains sound, and is preserved from fermentation and decay
for a long time. When the course of decay has advanced so far
that the grain has become unfit for food before it is treated with the
acid, it will when so treated be preserved in an inoffensive condition and
be suitable for manure.
Many marine vegetables are known to be useful as articles of food
both for man and beast,. and all marine vegetables are more or less
valuable for the purposes of manure. But these vegetable substances,
although they may be preserved for a considerable time by careful
desiccation and exclusion of damp, have a very strong affinity for
moisture, and when they have absorbed it are very liable to fer-
mentation, and become unsuitable for food, emit offensive odours, and
more or less rapidly lose their fertilizing properties. I prevent these
results, and preserve marine vegetable substances according to my
Invention by subjecting them to the action of sulphurous acid. This
I do as follows:-I either immerse the substance in an aqueous solution
of that acid for some time (my present experience is that about two
hours' immersion is sufficient) and then dry it thoroughly; after which
I find it advantageous to grind it into meal or powder; or I first dry the
substance and reduce it into meal or powder, and then subject such
meal or powder to the action of sulphurous acid by mixing it with that
acid in the form of a sulphite or bi-sulphite of soda, or other sulphite or
bi-sulphite reduced to powder. By either of these modes of treatment
the marine vegetable substances above mentioned can be preserved for
a long period of time.
When suitable for food they are preserved in a condition in which
they can be used as such, and when intended to be used as manure they

page_text: are preserved in an inoffensive condition and retain their fertilizing pro-
perties for a long period of time. The aqueous solution of sulphurous
acid which I find it most advantageous to employ is the solution usually
manufactured, of specific gravity about 1·012, mixed with an equal
quantity of pure water.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said James Dewar in the Great Seal Patent Office on
the 4th December 1868.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
DEWAR, Doctor of Medicine, in Kirkcaldy, in the County of Fife, in
North Britain, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Sixth day of June, in the year of our
Lord One thousand eight hundred and sixty-eight, in the thirty-first
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said James Dewar, Her special licence that I, the
said James Dewar, my executors, administrators, and assigns, or such
others as I, the said James Dewar, 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 AND
ARRESTING DECAY IN CERTAIN VEGETABLE SUBSTANCES FOR THE PURPOSES OF
FOOD AND MANUKE," upon the condition (amongst others) that I, the said
James Dewar, 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 James Dewar, 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:-

page_text: The vegetable substances to which my Invention relates are wheat,
oats, barley, and other grain, and also seaweed and other marine
vegetables. Most descriptions of grain are suitable for, food when
sound, and also form when sufficiently decomposed more or less valuable
manure for the fertilization of the ground. Many marine vegetables are
known to be useful as articles of food both for man and beast, and all
marine vegetables are more or less valuable for the purposes of manure.
But these substances, although they may be preserved for a considerable
time by careful desiccation and exclusion of damp, have a strong
affinity for moisture, and when they have absorbed it are very liable to
fermentation and decay, become unsuitable for food, emit offensive.
odours, and more or less rapidly lose their fertilizing properties.
The nature of my Invention is to arrest such decay when it has
commenced in those substances, and preserve them for such length of
time as may be desired from further decomposition, as also to preserve
those substances when decay has not commenced in a sound state
free from decay by subjecting them to the action of sulphurous acid.
The manner in which my Invention is to be performed is as
follows:-
First. As respects grain.-I subject any quantity of grain which I
desire to preserve, whether it be wheat, oats, barley, or other grain, and
whether it be in a sound condition or in a condition in which decay has
already commenced, to the action of sulphurous acid by immersing the
grain in an aqueous solution of that acid, and allowing it to steep.
'therein for a period of time sufficient to secure the thorough action of
the acid upon it. I find that an immersion of two hours duration is
sufficient for that purpose. I then dry the grain, to effect which object
I find it best to expose it to the action of dry air at a temperature of
from sixty to eighty degrees of Fahrenheit. When thus treated I find
that in the case of grain in which decay has already commenced the
course of decomposition is arrested, the musty appearance arising from
decay is removed, and the grain is preserved from further decay for a
long period of time, fermentation and other processes of decomposition
being arrested by the action of the acid. When the course of decay
has, before the grain has been subjected to the action of the acid,
advanced so far as to render the grain unfit for food, the grain will when
treated as before directed be preserved for a long period of time. in an
inoffensive condition, and be suitable for being converted in the usual

page_text: manner into manure.
subjected to the action of the acid it will remain sound and free from
decay for a long time after it has been so treated, even when exposed
to the action of the atmosphere or damp.
When the grain is sound at the time when it is
Secondly. As respects marine vegetables.-I immerse the marine
vegetable substance to be preserved in an aqueous solution of sulphurous
acid for a sufficient length of time to secure the thorough action of the
acid upon it. I find that an immersion of two hours duration is
sufficient for that purpose. I then dry the substance, to effect which.
object I find it best to expose it to the action of dry air at a temperature
of from sixty to one hundred degrees of Fahrenheit. After the substance
is dried I find it advantageous for convenience in keeping and for use
to break or bruise it or to grind it into meal or powder.
Another manner in which I perform this portion of my Invention is
to dry the marine vegetable substance and reduce it into meal or powder,
and then subject such meal or powder to the action of sulphurous acid
by mixing that acid thoroughly with it in the form of sulphite or
bi-sulphite of soda, or other sulphite or bi-sulphite reduced to powder.
I find that for this purpose it is sufficient to mix one pound by weight
of the sulphite or bi-sulphite with one hundredweight of the substance
intended to be preserved. By either of those modes of treatment marine
vegetable substances can be preserved for a long period of time. The
aqueous solution of sulphurous acid which I find it most advantageous
to employ for the immersion of the grain and marine vegetable
substances intended to be preserved in that manner is the solution
usually manufactured, say of specific gravity of 1.012, mixed with an
equal quantity of pure water. The quantity I use of this solution is
so much thereof as will completely immerse the substance intended to
be preserved.
In witness whereof, I, the said James Dewar, have hereunto set
my hand and seal, this Second day of December, in the year of
our Lord One thousand eight hundred and sixty-eight