IMPROVEMENTS IN THE METHOD OF DIVIDING ELECTRIC LIGHT, AND APPARATUS THEREFOR."
Year: 1878

page_text: PROVISIONAL SPECIFICATION left by August Reimenschneider and Frederik
Sinding Christensen at the Office of the Commissioners of Patents on the 19th
November 1878.
AUGUST RIEMENSCHNEIDER and FREDERIK SINDING CHRISTENSEN, both of Nestred,
in Danemark. "IMPROVEMENTS IN THE METHOD OF DIVIDING ELECTRIC LIGHT, AND
APPARATUS THEREFOR."
By this method of dividing the electric light, viz., of distributing the electric
light over a number of lamps supplied from one source, the division is attained by
a resistance coil made to form part of a branch of the electric circuit so that two
separate branches of the same current pass one through the coil, the other through
the light apparatus, and afterwards reunite. The resistance in the coil must be
equal to the resistance in the light apparatus, and the coil works both as a medium
for maintaining the tension of the current and for securing the connection of the
same through the whole circuit. The application of the coil is singularly important
by the introduction of a new kind of light apparatus hereafter to be described that
shows a marked superiority over all others formerly known by forming compara-
tively very small resistance to the electric current, the electric light being produced
in a vacuum or in a space almost entirely void of air between two graphite, carbon,
or platinum points.
A form for the new light apparatus is given on the Drawing in perpendicular
section. B, B, are the two carbon, graphite, or platinum heads between which the
light is formed placed in a glass tube A. The latter is closed at the bottom by a
metallic stopper D, at the top by the bottom of a metallic cylinder F. One of the
carbon heads is fixed on the metal stopper D or on a metal foot G on the top of the
stopper so that the circuit can pass through from the stopper to the carbon head.
The other carbon head B is fixed on the end of the piston rod E which passes
airtight through the bottom of the cylinder F, and is attached to another somewhat
larger piston H that can move air tight up and down in the cylinder F, and from
which the current can pass through to the carbon head B. The air in the glass

page_text: tube A has been pumped out entirely or partly by a common air pump through the
pipe on which the cock is. In the ring shaped space in the cylinder F around
the piston rod E and under the piston H there is atmospheric air that is compressed
by the pressure of the atmosphere and consequently by its tension counteracts the
same. The amount of the compressed atmospheric air under the piston H and con-
sequently the place of the latter in the cylinder F and the place of the carbon head
B on the glass tube A can be regulated through an aperture closed at the outside
by a screw, at the inside by a leather valve. The stopper D is embedded in a
holster d which by some feet is fixed to an insulating foot piece I made for instance
of wood. On the foot piece are placed the two brass bands x and x.
These are
connected one by the screw 6 the other by the screw 2 with each one end of the
wire L and by the screws 5 and 3 with each one end of the resistance coils wire.
Moreover the band x is connected with the stopper D by the screws 4 and kand by
the wire l, and the band x is connected with the piston E by the screws 1 and 3 and
by the wire . Both the resistance coil and the carbon heads can at the same time
be separated from the circuit by the application of a stopper o between the bands x
and x into two corresponding cuts in these; K is a lamp shade holder.
In passing through the apparatus the electric current will be divided, one part of
the current going through the carbon beads the other passing through the resistance
coil. In the band the two branches reunite and the current hence passes to the
next.light apparatus in the circuit. Before the current is made to pass through the
carbon heads, these nearly touch one another. As soon as the current is started the
light between the heads is produced and the heat developed by the light will make
the exceedingly rarefied air in the tube A expand. Consequently the piston will
arise whereby the light between the heads will be made longer. When the piston
in this way will have risen so much that the light shall have got its greatest power
it is prevented from being lifted still more by a regulating screw S, the nut of which
is placed in a cross fixed to the upper end of the cylinder. By the regulating screw
the power of the light of course can be varied at pleasure. If unfortunately from
some cause or other the light in one apparatus should go out it does not follow that
the lights in the other apparatus likewise will go out, the whole current in the
extinguished apparatus then passing through its resistance coil. For putting out
the light the stopper o is used by putting in between the bands x and x. The air
in the tube then will be condensed so that the carbon heads again will get nearer
to each other.
The light apparatus may, however, be constructed otherwise than aforesaid
without the essential part of the Invention thereby being modified. Thus the rare-
fied space around the carbon heads may also be kept separated by a mercury
column counteracting the pressure of the atmosphere as in the barometer.