A NEW OR IMPROVED APPARATUS FOR DETECTING COUNTERFEIT COIN."
Year: 1875

page_text: LETTERS PATENT to Charles Henry Stearn, of Liverpool, in the
County of Lancaster, for the Invention of "A NEW OR IMPROVED
APPARATUS FOR DETECTING COUNTERFEIT COIN."
PROVISIONAL SPECIFICATION left by the said Charles Henry Stearn
at the Office of the Commissioners of Patents, with his Petition,
on the 16th April 1875.
I, CHARLES HENRY STEARN, of Liverpool, in the County of Lancaster,
do hereby declare the nature of the said Invention for "A NEW
OR IMPROVED APPARATUS FOR DETECTING COUNTERFEIT COIN," to be as
follows:-
.This Invention has for its object the detection of counterfeit coin by
making the coin to be tested, if it be counterfeit, act as one of the plates
or conductors of a galvanic battery to produce an electric current
through an electro-magnet, and the presence of which electric current
and consequently the counterfeit nature of the coin being rendered
apparent by the deflection of a magnetic needle.

page_text: In carrying out my Invention I employ an electro-magnet and a
magnetic needle, the latter so disposed with regard to the magnet that
the deflection shall be as great as possible, and to one of the wires of tho
magnet I attach a plate of standard silver which is covered by baize,
felt, or other absorbent material saturated with water impregnated with
common salt, the other wire from the magnet is connected to a metallic
flexible arm which is capable of being depressed on to the coin placed
on the baize covering, as herein-after described.
The action of this apparatus is as follows:-The coin to be tested is
first placed upon the moistened baize covering, and the flexible arm is then
caused to descend upon the coin so as to establish a metallic contact
therewith; when if such coin is of inferior metal an electric current will
be produced which will cause the magnetic needle to be deflected, and
such deflection may be indicated upon a dial marked with the words
good" and "bad," the needle always remaining pointing to the word
good" which corresponds to the north pole, until an clectric current is
sent through the apparatus when it is instantly deflected to the word
"
"had"

page_text: nistrators, and assigns, or such others, as I, the said Charles Henry
Stearn, 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, within the United Kingdom of Great
Britain and Ireland, the Channel Islands, and Isle of Man, an Invention
for "A NEW OR IMPROVED APPARATUS FOR DETECTING COUNTERFEIT COIN," upon
the condition (amongst others) that I, the said Charles Henry Stearn,
my exccutors or administrators, by an instrument in writing under
my, or their, or one of their hands and seals, 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 Charles Henry Stearn, 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 :—
This Invention has for its object the detection of counterfeit coin, by
making the coin to be tested if it be counterfeit act as one of the plates
or conductors of a galvanic battery to produce an electric current and
the presence of which electric current and consequently the counterfeit
nature of the coin being rendered apparent by the deflection of a mag-
netic needle.
In order that this my said Invention may be the more readily seen
and understood, I have hereunto annexed a full size Drawing of the
apparatus, Fig. 1 representing a plan of my improved counterfeit coin
detector, and Fig. 2, a side sectional view of Fig. 1, through the
line a-b. Similar letters denote similar parts on both the views.
A is a circular wooden stand, in the centre of which is fixed an
ordinary magnetic needle B. The interior of this stand is recessed, as
scen more clearly in Fig. 2, and in this recess is fixed an electro-magnet C
with its north pole nearest to the north extremity of the magnetic
needle. The wire D passing from the same north end of the magnet is
connected to a plate of standard silver E which is covered by a covering F
(hereinafter called the moistened pad) of baize, cloth, felt, or other
absorbent material capable of being saturated, by preference, with a

page_text: so to affix it with regard to the needle B as to cause as great a deflection
of the latter as possible, I claim,-
1st. Employing an electric current for the purpose of detecting the
counterfeit nature of coin in the manner and by the combination of
apparatus herein-before described and illustrated on the accompanying
Drawing or any mere modification of the same.
2nd. The combination and arrangement of an electro-magnet and
magnetic needle, substantially as and for the purpose herein-before
described and illustrated on the accompanying Drawing.
In witness whercof, I, the said Charles Henry Stearn, have here-
unto set my hand and seal, this Fifteenth day of October,
in the year of our Lord One thousand eight hundred and seventy-
five.