A NEW OR IMPROVED ELECTRIC METER
Year: 1883

page_text: PROVISIONAL SPECIFICATION left by the said Arthur Stanley Butler at the
Office of the Commissioners of Patents on the 20th February 1883.
ARTHUR STANLEY BUTLER of St. Andrews in the County of Fife in North
Britain "A NEW OR IMPROVED ELECTRIC METER
"
My invention relates to the construction of an electric meter, in which, by the
combined action of a voltameter and a eudiometer on a counting and registering
apparatus of any known kind, a record is furnished of the quantity of electricity
passed through a circuit in a given time.
For this purpose, I lead a shunt from the main circuit through a resistance
which, with the other parts of the shunt circuit is adjusted to determine the
passage of a known fraction, such as 1/100 th of the total current, so that, by
measuring this fraction, the total current can be readily determined. The shunt
circuit, after passing the resistance, divides into branches, the one branch leading
back to the main circuit through a voltameter, in which two platinum plates are
arranged in a vessel containing acidulated water, and the other branch to a contact
plate. The voltameter vessel communicates at its upper part with the tube of a
eudiometer which is closed at its top, but which at its bottom communicates by a
bent tube with a vertical tube containing mercury. The bent tube is charged
with liquid such as bisulphide of carbon, to separate the mercury from the
acidulated water in the eudiometer. In the mercury tube there is a float, the stem of
which carries a pawl engaging with the ratchet wheel of a counter, and this stem
extends upwards within an adjustable distance of the contact plate above referred
to. The mercury in the vessel is electrically connected to one electrode of the
primary coil of an inductor, the other electrode of which is connected back to the
main circuit. The secondary coil of the inductor is connected to two platinum
points in the upper part of the eudiometer. The apparatus acts in the following
manner. The water in the voltameter. vessel is decomposed by the current passing

page_text: between the platinum plates, and the oxygen and bydrogen liberated collect in the
upper part of the eudiometer producing a pressure which causes the liquid in the
eudiometer to descend, and causes the mercury in the tube connected with it to
rise. The float is thus raised and the pawl on its stem turns the ratchet wheel of
the counter one tooth. The stem, in its farther ascent, meets the contact plate,
and thus closes the second branch of the shunt circuit. The current now passes
down the float to the mercury, and thence through the primary coil of the inductor,
and the current thus induced in the secondary coil, passing as a spark between the
platinum points at the top of the eudiometer, fires the gaseous mixture there
reproducing the water that had been decomposed. The mercury float now descends
opening the inductor branch of the shunt circuit, and the action is continuously
repeated, the counter registering the number of times a certain quantity of water
is decomposed, and so giving a measure of the electricity that has passed through
the voltameter. The contact plate, instead of being fixed, may be hinged, and
acted on by a metal rod, which expands and contracts under changes of
temperature, so that the ascent of the mercury float, before contact is made by its
stem, is automatically adjusted to suit the temperature. The stem of the float is
provided with an adjusting screw, by which it can be lengthened or shortened, so
as to determine the volume of the gases collected in the eudiometer before the
contact is made which causes their combustion.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Arthur. Stanley Butler in the Great Seal Patent Office on the
3rd August 1883.
ARTHUR STANLEY BUTLER of Saint Andrews; in the county of Fife, in North
Britain. "A NEW OR IMPROVED ELECTRIC METER
"
My invention relates to the construction of an electric meter, in which, by the
combined action of a voltameter and a eudiometer on a counting and registering
apparatus of any known kind, a record is furnished of the quantity of electricity
passed through a circuit in a given time.
The accompanying drawing shews diagrammatically the arrangement of
apparatus which I adopt for this purpose. A is a vessel containing acidulated
water, and B B are platinum plates immersed in the water, these being connected
by branch conductors 6 6¹ to the conducting line L L', the current passing through
which is to be measured. In either or both of the branch conductors b b¹, I
introduce a resistance which is adjusted to take a known fraction, such as Toth, of
the current. Under the vessel A extends a bent tube C C¹ containing mercury.
In its lowest part, a conducting wire c is sealed hermetically, this being always in
contact with the mercury and connected by a branch conductor c¹ with one of the
main conducting lines. At the top of the bent tube C, I fix a wire D which is
connected to one end of the coil of an electro-magnet M, the other end of this coil
being connected to the other main conducting line. In front of the magnet M is
mounted an armature lever F which is kept away from the pole of the magnet by
a weight or spring. This lever carries a spring pawl engaging with the teeth of a
ratchet wheel which works the gearing of a counter E. Beside the lever F is fixed
a contact spring S, near a contact point P which is connected to one of the main
conducting lines,; to the other line the spring S is connected through the primary
coil of an inductor I. The secondary coil of the inductor is connected to two
platinum points QQ in the upper part of the vessel A.
The action of the apparatus is as follows:-The fraction of the current of L L'
which passes through the plates B B decomposes a portion of the acidulated water,
and the gases produced accumulate in the upper part of the vessel A pressing down
the liquid and causing the mercury to rise in the limb C' of the bent tube. When
the mercury comes in contact with the wire D, the circuit is closed through the
coil of the electro-magnet M which thereupon attracting its armature, moves the
lever F. This movement is imparted by the pawl to the counter, and at the same
time, the lever moves the spring S to contact with the point P, closing the circuit
of the primary coil of the inductor I. The secondary coil of the inductor being
thus excited, a spark passes between the points QQ and ignites the gaseous
mixture in the vessel A. On condensation, the liquid again rises in A, and the
mercury descends in C', and the action is repeated as long as the current flows.
The counter E registering the number of strokes of the lever F, shews the number
of times the action has taken place, and the capacity of the gas space in A being
known, the amount of current can be determined. As there is a sudden develop-
ment of pressure when the gaseous mixture is ignited in A, I throttle the pipe C
so as to retard the ascent of the mercury therein.
Having thus described the nature of my invention and in what manner the same
is to be-performed, I claim:-
The construction of an Electric Meter consisting of a vessel wherein acidulated
water is decomposed by an electric current and the gaseous products are ignited, in

page_text: combination with a column of mercury and contact wire, and an electro-magnet
working a counter and making a contact for firing the gases produced by the
decomposition, arranged and operating substantially as herein described.
In Witness whereof I the said Arthur Stanley Butler have hereunto set my
hand and seal this Thirtieth day of July. in the year of our Lord one thousand,
eight hundred and eighty-three.
A, S. BUTLER, (L.S.)