IMPROVEMENTS IN THE PREPARATION OR PRODUCTION OF SPONGY METALS AND IN THEIR APPLICATIONS
Year: 1865

page_text: PROVISIONAL SPECIFICATION left by John Henry Johnson at the Office
of the Commissioners of Patents, with his Petition, on the 15th August
1865. A communication from abroad by François Drivet, of Turin, in
the Kingdom of Italy, an Adjutant in the Army of His Majesty the King
of Italy.
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of
Middlesex, Gentleman, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN THE PREPARATION OR PRODUCTION OF SPONGY METALS AND IN
THEIR APPLICATIONS," a communication to me from abroad by François Drivet,
of Turin, in the Kingdom of Italy, an Adjutant in the Army of His Majesty
the King of Italy, to be as follows:-
This Invention has for its objects the production of metals in a spongy or
porous condition, and the application of such metals to various useful
purposes, amongst the most important of which are electric batteries and the
lining of the interior of steam generators. In preparing spongy or porous
copper according to this Invention a saturated solution of sulphate of copper
(or of any other metallic salt according to the metal required to be produced
in a spongy state) is precipitated by means of a galvanic current. To this
solution is first added, in the proportion of from five or six times its volume,
water acidulated with one-third of its own weight of sulphuric acid. The
Inventor commences to precipitate this solution in the amorphous state upon
the plate which is to receive the spongy metal by means of a galvanic current
produced either by a simple or compound apparatus, that is to say, with a

page_text: diaphragm or by the battery, using at the same time a platinum ring in the
bath. When the solution is reduced the galvanic current is allowed to
continue for the period of about one hour, in order that the hydrogen in being
disengaged from the amorphous preparation may cause it to assume a spongy
and highly porous condition. The current is then interrupted in order to
allow the liquid to be re-saturated by means of sulphate of copper, in crystals
contained in a small bag which is suspended in the liquid on one of the sides
of the vessel. So soon as the solution is sufficiently saturated the current is
re-established until the spongy metallic mass has attained a sufficient solidity.
During the process care should be taken not to stir or agitate either the plate
or the solution, in order that the metal may acquire all the porosity possible.
The same process is required. for obtaining any other metal in a porous or
spongy state. In this condition the metal so prepared may be used as a
substitute for what has hitherto been improperly called spongy platinum, but
which in reality consists of an informal aggregation of molicules divided by
means of threads of the same nature. The interior of generators may be
lined with this spongy metal, whereby a larger heating surface is obtained, but
the most important and special application of this novel preparation of spongy
copper is its use as the electro-negative element in batteries of one liquid. In
this application the battery will consist of a vessel of any suitable form of glass,
gutta percha, or other suitable material. In this vessel are placed two
electrodes, as in the Wollaston battery, the zinc and the copper being in
the form of plates of the same size at a distance apart of from 1 to 2
inches. The interior of the vessel is filled with fine sand moistened with
water which has been acidulated by the addition thereto of th part of
sulphuric acid. This préparation of copper when employed as an electro-
negative element will by reason of its great porosity present in a small compass
a very large surface.