IMPROVEMENTS IN THE MANUFACTURE OF PHOSPHORUS
Year: 1872

page_text: LETTERS PATENT to Joseph Theodore Dann, of 43, Cowley Road,
North Brixton, in the County of Surrey, Civil Engineer, for the
Invention of "IMPROVEMENTS IN THE MANUFACTURE OF PHOSPHORUS.'
1
A communication from abroad by Gustave Ferdinand Féron, of
Ravan in the Commonwealth of France Marchant
Sealed the 22nd November 1872, and dated the 5th June 1872.
PROVISIONAL SPECIFICATION left by the said Joseph Theodore Dann
at the Office of the Commissioners of Patents, with his Petition, on
the 5th June 1872.
I, JOSEPH THEODORE DANN, of 43, Cowley Road, North Brixton, in
the County of Surrey, Civil Engineer, do hereby declare the nature of
the said Invention for "IMPROVEMENTS IN THE MANUFACTURE OF PHOSPHORUS,**
being a communication to me from abroad by Gustave Ferdinand
Féron, of Rouen, in the Commonwealth of France, Merchant, to be as
follows:-
This Invention has for its object so to simplify the process of manu-
facturing phosphorus as to reduce the amount of labour and quantity of

page_text: fuel required therefor, as well as generally to realize a greater useful
effect than can be obtained by any of the methods at present in use.
To this end I dilute one hundred parts of phosphate of lime in a quantity
of water of about ten times the weight thereof. I add from ninety-six
to one hundred parts of sulphuric acid or the corresponding quantity
of a more hydrated acid, and intimately mix both together until the
decomposition is complete. I then separate the acidic solution from
the precipitated sulphate of lime. Having washed this sulphate and
evaporated the solution so as to concentrate it to a thick syrup according
to the method hitherto in use, I add to the acidic syrup thus produced
a quantity of pulverized vegetable charcoal equal to it in weight, and
having completely dried the mass I place the same in a tube of
cylindrical or other suitable shape made of cast iron or any other
appropriate substance. I provide another tube, herein-after called the
retort, of about three times the length of and made by preference of
the same material as the one described, and of sufficient width to admit
of the smaller tube being inserted therein in the manner generally
known by the name of telescope fashion. The portion of the retort not
intended to be occupied by the smaller tube I fill with charcoal, and I
arrange either three, five, or any other suitable number of such retorts
in a furnace, and furnish the same with the requisite outlets. The
retorts, of which about two-third parts are thus filled with charcoal, I
expose to the action of the fire, and having brought the charcoal up to
red heat I insert the smaller tubes in the manner herein-before pointed
out, and I leave each of them in its place until the phosphorus has been
entirely extracted. I then substitute fresh small tubes for the exhausted
ones, and at the same time keep up the requisite supply of charcoal in
the retort. The whole of the volatilized phosphoric acid is thus forced
through the mass of charcoal in the retort, and the utmost useful effect
derived from the operation.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Joseph Theodore Dann in the Great Seal Patent
Office on the 4th December 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOSEPH
THEODORE DANN, of 43, Cowley Road, North Brixton, in the County 3
of Surrey, Civil Engineer, send greeting.

page_text: fitted on by means of screws and nuts or by other appliances. To the
rear end of each retort I prefer to attach or fix a cover or lid C, which
may be secured thereto by means of screws or by any other appropriate
closing arrangement. D is the furnace; E, E, are the furnace doors;
F is the fire-grate; the whole of these latter parts I prefer to build up,
and generally arrange along with the masonry in the manner usual in
the distillation of coal gas or of kindred products.
The mass of phosphate of lime and charcoal prepared in the manner
herein-before described I place in the "telescope" tube B, to the part
of which held between the inner surfaces of the masonry I prefer to
give about one-third of the length of the corresponding part of the
retort A, into which I insert the said tube, closing and securing it
hermetically by means of any of the usual mechanical appliances, after
filling with charcoal the part of the retort which is not to be occupied
by the tube B; and of such charcoal I keep up a constant supply in the
retort by replenishing the same whenever required on exchanging the
tubes B, as herein-before alluded to.
By the process of distillation described, to which I expose the mass in
the tube B, the whole of the phosphorus in the said mass is forced
through the charcoal in the retort A.
With the lid or cover C I prefer to connect a pipe G, either by casting
or forming the same in one piece with such lid or cover, as shewn in
Figure 1, or by fitting it thereto by means of a flange joint, or in any
other suitable manner. By this pipe the volatilized phosphoric product
forced through the charcoal in the retort is made to pass directly or
indirectly to the dip pipes which I introduce into a cooling vessel or
recipient described in the following.
In Figure 4 I have shewn a sectional diagram of a recipient for the
refrigeration and condensation of the phosphorus produced in the
distilling retorts shewn in Figures 1, 2, and 3. This recipient is a vessel
made by preference of tin plate and of appropriate size and shape, into
which I introduce the dip pipes H proceeding from the outlets G, shewn
in Figure 1, and connected with these by means of intermediate piping,
according to the method usual in the manufacture of coal gas, or in any
5 other suitable manner. The ends of these dip pipes H I immerse in the

page_text: gas or liquid, by preference water, with which I fill the recipient I;
and for each set of retorts I prefer to arrange duplicate recepients, as
shewn in plan in Figure 6, into each of which one branch of the inter-
mediate pipe J, connected with the outlet G, Figure 1, is introduced.
Each branch being fitted with a cock or tap K the volatilized phosphoric
product may, as soon as one of the recipients is sufficiently full, be shut
off by turning off the cock of the branch leading thereto, and led
into the other recipient by turning on the cock of the branch pipe
which is connected therewith. The dip pipes H I prefer to introduce
into the recipient in a slanting position, as illustrated in Figures 4.
and 5, so that the mouths thereof are immersed in the water or other
liquid with which the recipient is filled. I also furnish each recipient
with a water pipe L for maintaining the proper level of the liquid
therein, and with an exhaust pipe M for the carrying off of superflous
gases. In order to keep the liquid in the recipient cool I place the
same in a bath, as shewn in Figure 4, fed by a continuous current of
water.
Having now described the nature of the said Invention, and illustrated
the same in the annexed Sheet of Drawings, I wish it to be under-
stood that I do not claim the use of retorts for the distillation of
phosphorus, this having been known and practised heretofore; neither
do I claim the use of charcoal for such purpose; but what I do

page_text: Fourthly. The use or employment of recipients for the condensation
and refrigeration of the volatilized phosphoric product in connection with
the distilling retorts in the manner herein described and illustrated in
the accompanying Sheet of Drawings.
In witness whereof, I, the said Joseph Theodore Dann, have here-
unto set my hand and seal, this Third day of December One
thousand eight hundred and seventy-two.
JOSEPH THEODORE DANN. (L.S.)