A NEW CHEMICAL PRODUCT APPLICABLE TO THE ELECTRICAL PILE AND TO OTHER USES
Year: 1868

page_text: PROVISIONAL SPECIFICATION left by William Edward Gedge at the
Office of the Commissioners of Patents, with his Petition, on the
17th April 1868.-A communication from abroad by Pierre Rondel,
of 15, Passage des Petites Ecuries, Paris, France, Professor of
Sciences.
I, WILLIAM EDWARD GEDGE, of the Firm of John Gedge and Son,
of No. 11, Wellington Street, Strand, in the County of Middlesex, Patent
Agent, do hereby declare the nature of the said Invention for "A NEW
CHEMICAL PRODUCT APPLICABLE TO THE ELECTRICAL PILE AND TO OTHER USES," a
communication to me from abroad by Pierre Rondel, of 15, Passage
des Petites Ecuries, Paris, France, Professor of Sciences, to be as
follows:-
This new chemical product is obtained by the reaction of a mixture
of chlorate of potash and of chlorhydric acid on mercury. The immediate
result is a chlorhydrate of a double chloride of mercury and potassium,
when the reaction is over this salt is obtained at about 95 degrees
"Fahrenheit" (35 degrees centigrade) in a mass composed of fine
prismatic needles imprisoning between them a colored liquid which
is a solution of the salt in an excess of chlorhydric acid. The crystals

page_text: which remain after the mass has been compressed are not fusible under
140 degrees Fahrenheit" (60 degrees centigrade). If the entire mass
be raised before the expulsion of the liquid to temperature of about
262 degrees Fahrenheit" (110 degrees centigrade), it dries up and
abandons the major part of the chlorhydric acid which may be collected,
and it may be deprived of the acid to any desired extent by increasing
the heat. Bondlay and Bondorff were the first discoverers of several
double chlorides of mercury and potassium, but they obtained them by
mixtures of chloride of mercury and chloride of potassium, which was
much more costly, further these double chlorides did not contain so much
mercurial chloride as mine and were not combined with chlorhydric
acid I prevent as much as possible the formation of oxydes of chlorine
by suitable dosing, not putting in all the chlorate of potash at once,,
and keeping the mixture in agitation until complete decomposition of this
salt. In certain seasons the operation is effected without heating, and
it is never necessary to heat to above 95 or 104 degrees Fahrenheit (35. to.
40 degrees "centigrade"). The proportions of chlorate of potash, chlor-
hydric acid, and mercury are not absolute, and if it is desired to have a
double chloride with six equivalents of chloride of mercury for its equiva-
lent of chloride of potassium, 205 parts of chlorate of potash are taken
to 100 parts of mercury, and about 234 parts of chlorhydric acid," this
latter proportion may be varied. This new product has been tried
either disengaged or not from chlorhydric acid with every form of pile
with or without porous vase charcoal and zinc, or platina and zinc,
and a very constant and close current has always been obtained.
Amongst the new forms of piles without porous vase which have
been originated by the Inventor of this new product are the two
following:-

page_text: Secondly. The bottom of a vase is covered with mercury, and plunging
therein is the end of a platina wire coated in the rest of its length until
towards the other end with some isolating substance; this is however
not indispensable. At the upper part of the vase is placed a zinc
cylinder, one of the liquids above indicated is added and a quantity of
the new salt is projected upon the mercury depending upon the time
during which the pile is to act. This new pile may render important
services for galvanoplastic or other applications, the current being very
constant and energetic, and the polarization only manifesting itself
working many consecutive horns and not at all if properly attended
to. This new product is not only applicable to the galvanic pile, by
heating it to a not very high temperature it deploys into mercurial,
chloride, or corrosive sublimate which is gathered in the upper part
of the retort, and a chloride of potassium which remains at the bottom
of the apparatus, and which may be again brought back to the state of
chlorate of potash by well known means. It may therefore serve as a
new process of preparing corrosive sublimate or mercuric chloride and
of calomel or mercurous chloride.