Year: 1897

page_text: Date of Application, 19th June, 1897-Accepted, 9th Oct., 1897
invention and in what manner the same 1$ to be perforined to be particularly
described and ascertained in and by the following statement:--
My invention relates to a process and apparatus for effecting the preservation of
organic substances.
The apparatuses of my invention hereinafter described, and which I employ for the
preservation of organic bodies, have for their special characteristic the use of a bath
under pressure of the preservative substances in such manner as to cause them to
operate constantly at the ordinary temperature, and without the application of
artificial heat.
My apparatus is composed essentially of a generator capable of producing carbonic
anhydride by means of bicarbonate of soda and hydrochloric acid a reaction of which
the chemical formula is
CO³NaH + HCl == NaCl + H2O + CO².
This generator is composed of a cylinder A of steel plate lined with lead. This
cylinder is provided with an agitator with paddles which can be actuated by means of
a handle D the shaft of which is provided with a stuffing-box. An orifice closed by a
screw plug a is provided for the introduction of the bicarbonate of soda. Upon this
cylinder is placed a second cylinder B also lined with lead and containing hydrochloric
acid which is filled into it through the aperture closed by the screw plug b. A central
bart threaded at its upper part is actuated by means of a handle m, and bears at its
lower end a conical piece S forming a valve upon the bottom of B and which, when
the bar t is turned allows the acid to flow upon the bicarbonate. The lead pipe N
secures the equilibrium of pressure between A and B. Two tubes G1 G2 convey the
carbonic anhydride produced in A to the receivers R¹ R². These latter are constructed
of steel plate and contain upon the metallic partitions with which they are provided
the materials which are to be treated. Pressure gauges m¹ indicate the interior
pressure, hooks or rings C are provided for the convenient handling of the covers H.
which are clamped and luted upon the receivers. The intermediate containers 0 0¹
are arranged to cause the carbonic anhydride to pass from the two receivers into two
other receivers without danger of loss of gas, thus causing the operation to be
continuous. The cylindrical projections X are secured upon the outer walls of the
receivers, and are traversed by silver wires, which pass from the interior to the
exterior, and serve to conduct the electric current. The operation is carried out as
follows:-
The receivers R¹ R² are filled with material to be preserved, they are then
hermetically closed; the cylinder A containing a charge of bicarbonate of soda is
then placed in communication with the cylinder B by opening the valve S. The acid
flows gradually during which the bicarbonate is agitated by means of the handle B

page_text: of the agitator and carbonic anhydride is evolved, which passes upon opening the
cock placed on the tube G2 into the receivers R2 and R3 and permeates through the
materials placed therein. The pressure may vary from five to ten atmospheres
according to the dimensions of the apparatus, and the nature of the materials to be
treated. The operation lasts for about a quarter of an hour, during which time the
receivers R' and R² are filled and closed and the intermediate regulator () 1 causes
the carbonic anhydride to pass into them which is contained in R2 and R³. The
connecting cocks are then closed, and afterwards by means of the compressing pump P
communicating with each receiver by means of the tubes T provided with cocks
there is introduced into one or two receivers water charged with part of methylal.
The operation is rendered. continuous by means of intermediate receivers and
compressors and the cocks 2, two cylinders being filled with water whilst the two
others are filled with carbonic anhydride. At the end of about half an hour the
liquid is allowed to run out by means of the escape cocks in the lower reservoir, there
is added thereto the quantity of methylal absorbed by the materials, say about one
third of the quantity, and the escape cocks are again closed. The receivers are then
opened, and the treated products are removed and the vessel recharged in order to
repeat the operation by turning in by means of the intermediate containers and
compressors the carbonic anhydride contained in the other cylinders. Before making
use of the methylal the polymerisation of it and its change into trioxymethylene
(C3H6O3) is prevented by adding to it from 25 to 30 % of a neutral chloride, say of
chloride of sodium (NaCl) for instance, the loss of methylal is thus prevented. When
it is desired to preserve organic substances during a period of several months it is
necessary during their treatment in the bath of methylal to cause an electric current
to pass through them by aid of the silver wires passing through the parts X. The
current may be obtained from any convenient source of electricity, and the electrodes
may be formed of cylinders of carbon, or of silver. The current produces the
molecular agitation of the bath and decomposes the chloride of sodium producing
nascent chlorine, which adds to the antiseptic quality of the methylal, and in general
the penetration of the materials is more rapid. The said materials thus prepared are
then suspended in a well ventilated space without further precaution.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what I
claim is:
1. In apparatus for antiseptic and preservative purposes the use of a closed
generator lined with lead provided with an agitator, and capable of containing
bicarbonate of soda.
2. In apparatus for antiseptic and preservative purposes the use of a reservoir lined
with lead placed upon the generator set forth in Claim 1 and containing acid which
may be gradually allowed to flow to the interior of the generator by means of a screw
valve or otherwise.
3. In apparatus for antiseptic and preservative purposes the use of a series of
receivers in which can be placed the materials to be treated, and receiving the
carbonic anhydride produced in the generator, and connected together two by two.
4. In apparatus for antiseptic and preservative purposes the use of a connecting
pipe establishing equilibriumn of pressure between the generator and the reservoir.
5. In apparatus for antiseptic and preservative purposes the containing and
compressing apparatus which enables the carbonic anhydride after use in one vessel
to be passed from one series of vessels to another, avoiding the loss of gas, and
rendering the action continuous.
6. In apparatus for preservative and antiseptic purposes the use of a compressing.
pump for the purpose of introducing into each receiver at a pressure of about ten
atmospheres water charged with one four-hundredth part or thereabouts of methylal.
7. In apparatus for antiseptic and preservative purposes the use of an electric
current passing the bath of methylal for the purpose of decomposing the chloride
contained therein, and of hastening the penetration.

page_text: All substantially as and for the purposes above described, and with reference to
the accompanying drawings.
Dated this 18th day of June 1897.
W. P. THOMPSON & Co.,
322, High Holborn, London, W.C., Patent Agents for the Applicant..