IMPROVEMENTS IN THE PRODUCTION OF SALAMMONIAC IN A COMMERCIAL FORM
Year: 1866

page_text: LETTERS PATENT to Peter Spence, of Newton Heath, in the County
of Lancaster, Manufacturing Chemist, for the Invention of "IMPROVEMENTS
PROVISIONAL SPECIFICATION left by the said Peter Spence at the Office
of the Commissioners of Patents, with his Petition, on the 8th August
1866.
1, PETER SPENCE, of Newton Heath, in the County of Lancaster,
Manufacturing Chemist, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN THE PRODUCTION OF SALAMMONIAC IN A COMMERCIAL FORM,"
to be as follows:-
According to the usual method of producing salammoniac in a certain
commercial form the salt is first obtained in crystals, which are subsequently
treated by sublimation.
My Invention consists in dispensing with the process of sublimation and in
substituting a treatment by pressure. The crystals I obtain by any usual
chemical means, and then submit them to the action of an ordinary hydraulic
steam or other press, by which means they become solidified into a mass and
are prepared for commercial purposes. I have above spoken of the
salammoniac as being in the first instance in the state of crystals, but it may
.

page_text: be in a finely divided form which would not perhaps strictly be called
crystalline. The moulds in which the material is pressed may be heated by
any convenient means.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Peter Spence in the Great Seal Patent Office on the
8th February 1867.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, PETER
SPENCE, of Newton Heath, in the County of Lancaster, Manufacturing
Chemist, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Eighth day of August, in the year of our Lord One
thousand eight hundred and sixty-six, in the thirtieth year of Her reign, did, for
Herself, Her heirs and successors, give and grant unto me, the said Peter
Spence, Her special license that I, the said Peter Spence, my executors, adminis-
trators, and assigns, or such others as I, the said Peter Spence, 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, withiu
the United Kingdom of Great Britain and Ireland, the Channel Islands, and
Isle of Man, an Invention for "IMPROVEMENTS IN THE PRODUCTION OF SALAMMONIAC
IN A COMMERCIAL FORM," upon the condition, amongst others, that I, the said
Peter Spence, by an instrument in writing under my hand and seal, 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 Peter Spence, 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,
that is to say:-
My Invention consists in a method of obtaining salammoniac in the solid
form usually adopted in commerce; according to the ordinary method crystals
of the salt are first obtained, and these are treated by sublimation; according to
my Invention I dispense with this process of sublimation, and substitute a
treatment by pressure, whereby the particles become united in a solid block
resembling the well-known article of commerce; by this treatment also I

page_text: obtain greater purity, for when the process of sublimation is adopted the
salammoniac is liable to be contaminated with chloride o iron, which is of a
volatile nature.
In carrying out my Invention chloride of ammonium produced by any
ordinary chemical means may be used, but I prefer to take crystals of the
salt and dissolve them in hot water to saturation. This solution I allow to
settle so as to obtain a clear liquor, and it is then placed in a cooler and kept
continually stirred, by which means I obtain minute crystals or fine
granulated powder; this I drain thoroughly, or the moisture may be extracted
by the well-known centrifugal apparatus; I then place the drained powder
iu metal moulds of any desired form, and by means of plungers fitting the
said moulds submit it to pressure in a hydraulic or other press with sufficient
force to compress the particles into a solid cake. The amount of pressure.
required will, of course, vary with the size of the mould employed, and may be
determined by a short experience. Convenient sizes for the moulds may be such
as will hold from one to ten pounds, but that is a matter which may be
determined at pleasure. To facilitate the removal of the cakes the moulds may
be made slightly tapered, and they may be provided with loose bottoms, which
can be forced upward.
Having thus described and ascertained the nature of my said Invention, and
the manner of carrying the same into effect, I desire it to be understood that
I claim, as secured to me under the above in part recited Letters Patent, the
production of salammoniac in the commercial or cake form by compressing
crystals of or otherwise finely divided chloride of ammonium.
In witness whereof, I, the said Peter Spence, have hereunto set my hand
and seal, this Seventh day of February, in the year of our Lord One
thousand eight hundred and sixty-seven.