between the pointa;
and the auxiliary brush brushes divide
the sensitiveness when the brushes are ad-
io justed. 35
Signed this 16th day May, D.
Witnesses:
Geo.
20 instances where auxiliary brushes have
been used connection with the field-helices
said auxiliary brushes received the current
continuously and caused great sparking,
whereas invention the auxiliary brush
receives current only when the normal elec- 25
trical conditions the circuit are disturbed.
NIKOLA TESLA.
1885.
. Pinckney,
Wallace Seeeell.
The connection between the helices and the
5 auxiliary brush brushes may made a
wire small resistance, resistance may
be interposed (E, Pig.
I claim invention—
The combination, with the commutator and
main brushes and one more auxiliary
brushes, the field-helices the main cir- 30
cuits and one more shunt-connections from
the field-helices the auxiliary brushes, the
relative positions upon the commutator the
respective brushes being adjustable, for the
purpose set forth.The field-hélices may wound the same
direction, part may wound opposite
directions.
I aware that not new useauxiliary
brushes thecommutator,andthatauxiliary
brushes have been connected the field heli
ces; but not aware that the helices a
is series dynamo have been shunted means of
auxiliary brushes, and that the relative posi
tion the respective brushes has been varied
for the purpose regulating the current de
veloped the machine
