Improvements in Electric Railways.
Year: 1894

page_text: Date of Application, 16th Jan., 1894-Accepted, 24th Feb.,
1894
COMPLETE SPECIFICATION.
[Communicated from abroad by EDWARD HIBBERD JOHNSON and ROBERT
LUNDELL, both of Number 44, Broad Street, New York City, New York,
-United States of America, Electricians.]
Improvements in Electric Railways.
I, HENRY HARRIS LAKE, of the Firm of Haseltine, Lake & Co., Patent
Agents, 45 Southampton Buildings, in the County of Middlesex, do hereby
declare the nature of this invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
My invention relates to improvements in that type of electric railways in which
the current main or feeder supplying the propelling current is buried or insulated
throughout the length of the entire route and is provided with sectional trolley
conductors or rails located parallel thereto, each of said sectional conductors having
means for automatically connecting it to the current main and disconnecting it
therefrom as a car or vehicle passes over them, sail car or vehicle being usually
provided with one or more contacting brushes or trolleys which convey the current
to and through the propelling motor located thereon.
My invention has for its objects, First to prevent any possibility of the accidental
operation of the switching electro-magnets under any and all conditions of weather:
Second to so locate and arrange the switch boxes that they are exterior to the
road-bed, easy of access, and that their interior mechanism may be examined without
disconnecting any of the operative parts of the apparatus and this even while the
cars or vehicles are running regularly: Third to so arrange or locate the sectional
trolley conductors that no damage could occur to a person or animal in the event
of any one of said conductors having been left in a charged or live condition: Fourth to
so simplify the arrangement or construction and attachment of the conducting
contact brushes or trolleys that they may be especially efficient and little liable to
require repairs: Fifth to provide a method and means whereby it will be utterly
impossible for the sectional trolley conductors either in advance or the rear of a
travelling car or vehicle to receive any leaking current or be left in any way
charged or alive to the danger of passing persons or animals: Sixth to effect any
and all of the results necessarily attributable to the entire structure hereinafter
described, the essentially novel features of my invention being particularly herein-
after pointed out.
Referring to the accompanying drawings in which like letters of reference
represent corresponding parts
Figure 1 is a diagrammatic view of one form of my improved system, illustrating
in diagram also an electric motor and circuit connections therefor with the system.
Figure 2 is a similar view of the system illustrating also a storage battery and
circuit connections to the propelling motor for driving the propelled vehicle over
crossings and my improved form of conducting contact brushes or trolleys as
connected thereto.
Figure 3 is a cross sectional view taken through the road-bed of a tram-way,
illustrating in cross sectional view the current main with one of my improved switch
boxes, together with the circuit connections from the current main to the switch box
and sectional trolley rails and tram rails, all of said rails being shown in section and
the circuit connections and switch box in dotted lines.

page_text: Figure 4 is a cross section of the road-bed of a tramway illustrating my improved
manner of protecting the sectional trolley conductors so that when charged they
will not be harmful to persons or animals.
Figures 5 and 6 are respectively, detail side elevational and plan views of one of
my improved conducting contact brushes or trolleys, together with the operative
parts for controlling the movements thereof.
Figure 7 is an enlarged plan view of the interior of one set of switching devices
arranged in groups of three in an enclosing box, the lid of the switch box in this
instance being removed.
Figure 8 is a plan view of a complete enclosed switch box like that shown in
Figure 7, illustrating also the circuit connections running thereto and the manner
of suspending the switch box in a surrounding casing provided with an enclosing
cover which is shown as partly broken away.
Figure 9 is a cross sectional view taken through Figure 8 on the line 9-9 and
as seen looking in the direction of the arrows from the bottom toward the top of
the drawing.
Figure 10 is a cross sectional view taken through Figure 7 on the line 10-10
and as seen looking in the direction of the arrows upon that figure from the bottom
to toward the top of the drawing.
Figure 11 is a sectional view taken through Figure 10 on the broken line 11-11
and as seen looking in the direction of the arrows upon that figure from the bottom
toward the top of the drawing.
Figure 12 is a diagrammatic view illustrating my novel arrangement of circuits
and circuit controlling devices for preventing any possibility of leakage of current
between working or live sectional trolley conductors immediately under the car and
those adjacent thereto in front or in the rear of the car.
Figure 13 is a similar diagrammatic view to that shown in Figure 12 with
additional safety circuits attached to the operating electro-magnets for insuring
the positive operation of the armatures thereof from either of the conducting or
contact brushes.
Referring now to the drawings in detail,
R and R represent the tram-way rails of usual form resting either upon cross
ties T as shown in Figure 3 or upon longitudinal stringers T₁ T' which are supported
in turn by the cross ties, and S C and S C represent pairs of sectional trolley
conductors, preferably about six feet in length, and separated from each other by
proper spaces, said conductors being preferably of T-form grooved in their upper
sides and supported upon longitudinal stringers T' T' carried by the cross ties T,
the surface of the road which embraces the tram rails and sectional trolley
conductors being preferably of asphalt, as clearly shown in Figures 3 and 4.
F W represents the feed wire, preferably a lead covered cable, located in close
proximity to the road-bed and provided with branch conductors wow running into
the switch boxes A' which are preferably of iron and include each three sets of
switching electro-magnets M¹ M², M³ M², and M* M* secured in pairs to a slate
or other insulating base S which in turn is bolted to the inner face of the switch
box by bolts ss as clearly shown in Figures 8, 10 and 11.
The switch boxes A' are pivotally secured by ears a upon bolts or trunnions a², a³
attached to the inner surfaces of metallic frames which rest in turn upon the tops
of wooden protecting boxes A. A, the metallic frames being grooved in their upper
surfaces so as to admit of the reception of heavy iron lids A' A', which when the
boxes are in position rest flush with the street surface. The pivoted switch
boxes A³ are provided with separable protecting covers A which covers are secured in
place by bolts a³ extending through lugs or ears aª a³ as clearly shown in Figures 8
and 10.
One of the coils of each of the electro-magnets M' M³, M* M*, and M M is of
high resistance or many convolutions and the other coil, in each instance, is of low
resistance or few convolutions and the circuit connections to and through these
several.coils from the conductors ³ ³ 10 11 13 „13 and 2¼ to the sectional

page_text: trolley conductors SC, S C¹ and the tram rails R¹ and feed wire FW are such
that one coil of each magnet acts as a shunt to draw up the armature P¹ and its
lever P pivoted at p so as to bring the contact springs 2p into circuit relation
with the conducting standards L L and create a new or low resistance path for
the working circuit, as will be described more particularly in connection with the
description of the mode of operation.
The several insulated branch conductors w to w¹s inclusive enter the boxes A
and pass under the switch boxes A' A' and over the tops thereof, ultimately
entering said switch boxes through proper water tight gaskets on the upper front
edges thereof, the arrangement being such that when the covers A' are removed
and the switch boxes tilted upward through the agency of operating handles H ¤,
the incoming conductors will not be sensibly disturbed. In each of the switch
boxes and adjacent to each of the pairs of magnets are fuses F F F and ƒ ƒ ƒ
of sufficient current carrying capacity to meet the necessities of the case.
B₁ B' are conducting contact brushes or trolleys made preferably of wire secured
in each instance to a solid metal back, said brushes being of sufficient width and
length to fit in the grooved portions of the sectional trolley conductors SC, S C¹
and span or bridge the spaces between surceeding pairs of such conductors. They
are each secured to a triangular shaped support B³ in any preferred manner;
the back of the brush being usually grooved and adapted to slip endwise over the
T-shaped portion of the lower side of the support and held in place by a pin or
set screw not shown. The triangular shaped support B is pivoted to a pair
of links or arms bb by pins B' Bi which links in turn are pivotally secured by
pins b³ to a cross bar or arm I located beneath the body of the car. To the upper
end of the support B³ is secured a cord or chain which passes over a grooved
pulley to the platform of the car where it is accessible to the motor-man either
through the agency of a crank and pulley or any preferred operating mechanism,
the arrangement being such that the support B and its sustained brush B¹ B
may always be lifted and the brush remain with its lower edge parallel to its
position of support when resting in the groove of the sectional trolley conductor,
as clearly shown in full and dotted lines respectively in Figure 5. This manner of
supporting the brush also prevents it from jumping and enables all parts of it to be
constantly in contact with the sectional conductors as it moves along.
M represents an electric motor and H' the operating switch therefor, said switch
being of any preferred form and connected thereto by conductors 20 and
through an additional conductor to to the metallic frame of the car and ultimately
to the tram rails R through the wheels thereof, said motor being connected in turn
by branch conductors w³ ³ running to the conducting contact brush or trolley B²,
preferably such as already described and illustrated in Figures 5 and 6.
B represents a battery, preferably a storage battery, of sufficient electro-
motive force to operate the switching electro-magnets, said battery being connected
from one pole by conductor w through the frame work and wheels of the car and
tram rails R to earth; from the other pole to a binding post which is connected
in turn to and through and adjustable rheostat Rh, said rheostat being connected
on one side by a conductor w with one of the conducting or contact brushes or
trolleys B² and on the other to the remaining conducting contact brush or trolley B¹.
In the arrangement shown in Figure 2 the storage battery SB is approximately
of the same electro-motive force as the dynamo at the power house which is con-
nected to the feed wire F W, but is of comparatively small current capacity
sufficient to propel the car over short distances such as crossings, switches and
the like, said storage battery being directly in a derived circuit from the generator
with the propelling motor M, the rheostat Rh being used for diminishing the
current supply to the switching magnets through the conducting or contacting
brush B', it being the intention to lift the conducting or contact brushes B¹ B'
from the sectional trolley conductors by cords 6 on reaching crossings or other
obstructions where unnecessary expense might be incurred in the building of the
system to accommodate the conditions of affairs at such points.

page_text: A very essential feature of my invention consists in locating one set of the
sectional trolley conductors S C, S C outside of one line of the tram rails R,
the other set of such sectional trolley conductors S C' being located between the
lines of tram rails R and R', which tram rails, it will be understood, are connected
together electrically and to the usual return conductors G G, see Figure 3. By
thus arranging one set of sectional trolley conductors outside of the tram rails I
afford to the working current a path of much lower resistance from the other set
of such sectional trolley conductors thereby preventing any possibility of a
leakage from the inner set of sectional trolley conductors to the outer set, which
latter set it will be understood is operatively connected through working con-
ductors w, and we with the switch controlling magnets in the switch boxes A'A'.
This feature will be more fully explained in connection with the description of the
mode of operation later on.
In Figure 4 I have illustrated my improved manner of protecting the working
sectional conductors which convey the current to the propelling motor by locating
the said conductors slightly below the level of the road-bed and protecting them on
either side by blocks of stone D D embedded in the asphalt between the tram
rails, the arrangement being such that should a sectional conductor be left alive
or charged at any time a horse or person cannot, in passing over said conductor,
make electrical contact therewith. It will be understood of course that with this
arrangement of the conductors the conducting contact brushes B' will rest upon
the conductors S C in the groove formed by the blocks of stone D D. The other
set of sectional trolley conductors SC might be similarly protected or arranged
if thought best.
In Figures 12 and 13 I have illustrated a novel arrangement of circuits as
applicable to the two forms of apparatus shown in Figures 1 and 2 whereby all
current leakage from sectional trolley conductors immediately in advance and
immediately in the rear of a moving car is avoided. This is effected by providing
a high resistance shunt w" through a rheostat Rfrom each of the central
sectional trolley conductors to one of the tram rails or earth return conductor R',
the armature levers P of the several actuating electro-magnets M' M³, M³ M*,
M M being provided with back contacts p p p similar to the front contacts p
pp, which back contacts when resting in their normal position close these high
resistance shunts through fixed contacts L' L' L' so that said shunts will convey
any current leakage from sectional trolley conductors immediately in the front of
the car or in the rear thereof directly to the low resistance earth circuit or tram
rail R, the resistance of this circuit being always of course less than that which
would be given to the passage of the current between the ends of adjacent sectional
trolley conductors during extremely wet weather.
I will now proceed to describe the mode of operation of the entire apparatus
having reference particularly to Figures 12 and 13 for the complete circuit
connections through the high and low resistance coils of the electro-magnets M' M³,
M* M*, M* M*.
Referring first to Figure 1: Suppose a car, not shown, but provided with an
electric motor M, switch H', switch operating battery B, rheostat Rh, conducting
contact brushes or trolleys B₁ B' and the necessary circuit connections to be
standing in the position shown with the two conducting contact brushes B' B' just
leaving the front ends of the sectional trolley conductors SC, SC. Under this
condition of affairs when the contact brushes B' B' first passed from left to right
upon the sectional trolley conductors upon which they are now standing a circuit
was formed from battery B as follows: By conductor to, conductor w², conducting
contact brush B', conductor wº, see Figure 10, high resistance magnet M,
conductor w to earth where it returns to the other pole of the battery. This
energizes the electro-magnet M' and causes the armature to be drawn into its
forward position as shown, thereby closing the working circuit as follows: From
the generator by the feed wire FW, branch wire w¹, stationary contact points L,
movable contact points p³, low resistance coils of the electro-magnet M³, wire w³,

page_text: conducting contact brush B', wire w³, wire w³ through the switch H³, electric
motor M, wire w" to earth and to the generator. Consequently the car advances
and as the conducting contact brushes B' B pass upon the next pair of sectional
trolley conductors S C, S C' in advance, a similar circuit is closed from the
battery B by conductor 10 through the shuut coil of the switch operating
magnet M³, thereby elevating the armature lever P and closing the working circuit
through the low resistance coils of the electro-magnet M. The car continues to
advance therefore until the next set of sectional trolley conductors is reached when
in similar manner circuit is closed from the battery B by conductor w¹ through
the high resistance shunt coil M thereby bringing into circuit the low resistance
coil of the electro-magnet Me, the armatures of the electro-magnets M³, M³, M³, M*,
returning in sequence to their back stops as the sectional trolley conductors are
passed over by the brushes in pairs.
It will be observed that inasmuch as the switch actuating sectional trolley
conductors S C are located on the outside of the lines of tram rails or con-
ductors R R they are therefore at such a distance from the working sectional
trolley conductors S C which furnish the working current for the motor as
compared with the distance from said sectional trolley conductors to the line of
tram rails R that they afford a much higher resistance path to the working current
than does the line of tram rails R, so that if any leakage occurs at any time from
any one of the working sectional trolley conductors S C that current leakage will be
to the point of lowest resistance which will be either one or the other of the lines
of tram rails R R' and will not therefore be through any of the switch operating
magnets, a feature of great importance inasmuch as it makes it utterly impossible
for any current leakage to effect the switches in any manner.
In the arrangement shown in Figure 2, the storage battery S B is of substantially
the same electro-motive force as is the generator at the power house connected with
the feeder circuit F W, the current capacity of this battery, however, being very
small or only sufficient to move the car over brief distances, thereby avoiding the
necessity of carrying an undue load of battery. It is to be understood of course
that the storage battery S B is being charged in derived circuit during the time
that the car is in motion. The battery B in Figure 1 may be either a primary
battery or a storage battery having its charge regulating capacity controlled by
the rheostat R h.
I will now explain how current leakage from adjacent sections is avoided as the
car advances. By referring to Figures 12 and 13, it will be seen that as long as
the magnets M' M², M³, M, M M are demagn: tized, the armature levers P will
be in their lower positions with the contact points p, p, p' upon the back stops L',
L', L' thereby closing a circuit from each working sectional conductor S C¹ by
wires to, to and to and to in multiple to and through a rheostat Rh' and
conductor to to earth by the line of tram rails R'. The resistance of this circuit
is or should be very much lower than that which could be afforded to the current
between the ends of any two pairs of sectional trolley conductors SC or by a
person or animal standing thereon. It is apparent from inspection of the drawings
that these high resistance shunts are broken in succession to the sectional trolley
conductors as they are in sequence connected with the working circuit through the
motor, thereby avoiding any actual current leakage during the time that the
conducting brush B is resting upon that particular sectional trolley conductor
thus utilizing all of the current for propulsion of the vehicle.
It will be noticed upon examination of Figures 12 and 13 that the conducting
contact brush B' has a slight lead over the corresponding conducting contact
brush B to such an extent as to bridge the space between any adjacent pair of
sectional trolley conductors S C just before the brush B* bridges the corre-
sponding space between the corresponding adjacent pair of working sectional
trolley conductors S C. This is for the purpose of causing the next switching
magnet in advance to rupture the high resistance shunt w¹ to the corresponding
working sectional trolley conductor S C¹ before the working current is closed

page_text: through the conducting or contact brush B² thereby avoiding arcing at the back
contacts p L'. In the arrangement shown in Figure 13 certainty of action of the
switching magnets is assured by including the shunt circuits w" in additional coils
around the operating electro-magnets so that should the switching magnets fail to
operate through collected dirt or for any other imperfection between adjacent
sectional trolley conductors S C and the brush B' they will be operated by the
working current through the conducting brush B3 when it reaches the next sectional
trolley conductor in advance. With such an arrangement of circuits therefore the
operation of the switching magnets is made doubly sure.
When it is desired to examine any of the switching apparatus the cover A¹ to
that particular set of apparatus is removed from the box A and the switch
box A, A³ turned outward from the track through the agency of the handles H H
about the pivotal supports a' a' so that the switch box A' A' is wholly exposed,
the incoming conductors w³ to winclusive not being disturbed. The separable
part A³ of the box is then detached by removing the screw bolts a³ a³ and the
entire operation of the switching magnets is made visible to an attendant even
during the time that the cars are running, thus making it possible to detect any
defect in the apparatus without delaying traffic. This feature is deemed by me
also as of especial importance.
I do not limit myself to the special details of construction herein shown and
described. I believe it is broadly new with me to provide neaus for preventing the
accidental connection of any one of a series of disconnected sectional trolley con-
ductors with a current feeder or main, and my claims in this particular are therefore
broadly to means for effecting this result.
I believe it is also broadly new with me to prevent current leakage between
active or live sections of trolley conductors beneath the car and the adjacent
sections of such trolley conductors not for the time being connected to the
working circuit, and my claims in this particular are also of the most generic
Бсоре.
I believe also that I am the first to locate switch boxes wholly enclosing
electro-magnetic switching mechanism outside of the lines of the tram-rails and to
so arrange said switch boxes that they may be opened and examined while the
propelled cars or vehicles are in motion without disturbing the circuit con-
nections or delaying traffic upon the road, and my claims in this particular are
also generic.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, as communicated to me by
my foreign correspondent, I declare that what I claim is :-
1. In an electric railway system a current feeder or main insulated throughout
its length; a series of sectional trolley conductors having circuit connections and
electro-magnetic switching devices adapted to connect said sectional trolley con-
ductors to the current feeder or main in sequence; a second set of sectional trolley
conductors having circuit connections with the electro-magnets of said switching
devices, in combination with a leak circuit located between the two sets of sectional
trolley conductors whereby a leak from the working circuit can never accidentally
operate the switching magnets.
2. In an electric railway system a current feeder or main insulated throughout
its length, a series of sectional trolley conductors adjacent thereto and provided
with circuit connections and means for connecting them in sequence to the current
feeder or main; a second set of sectional trolley conductors having circuit con-
nections with electro-magnetic switching devices for connecting the first set of
sectional conductors to the feeder or main, in combination with an electrical
generator having one pole connected to the current feeder or main and the other to
an exposed return conductor located throughout its length between the two sets of
sectional trolley conductors.
3. In an electric railway system a current feeder or main insulated throughout

page_text: its length; working sectional trolley conductors provided with electro-magnetic
means for connecting them to the current feeder or main in sequence; a second
set of sectional trolley conductors provided with circuit connections to said electro-
magnetic means, in combination with a leak circuit between the two sets of trolley
conductors.
4. In an electric railway system a current feeder or main insulated throughout
its length; exposed sectional trolley conductors provided with means for connecting
them to the current feeder or main in sequence, in combination with a leak circuit
adapted to prevent accidental connection between any trolley conductor and the
current feeder or main.
5. An electric railway system provided with a safety leak circuit, substantially
as described.
6. An electric railway system provided with a current feeder or main; a series
of sectional trolley conductors provided with means for connecting them to the
current feeder or main in sequence, in combination with additional means for
preventing the accidental connection of any one of said sectional trolley conductors
with the current feeder or main.
7. An electric railway system having an insulated current feeder or main, a
series of exposed working sectional trolley conductors located between tram rails
which are electrically connected together and to earth and a series of exposed
switch actuating trolley conductors located outside of the tram rails, in combination
with switch actuating devices for connecting the working sectional trolley con-
ductors to the current feeder or main, said devices being electrically connected
with the outer line of sectional trolley conductors.
8. An electric railway system provided with a current feeder or main insulated
throughout its length and a series of sectional trolley conductors, in combination
with electro-magnetic switching devices and circuit connections for automatically
connecting said sectional trolley conductors to the current feeder or main in
sequence, said switching devices being enclosed in removable switch boxes located
outside of the lines of tram rails, the arrangement being such that the switch boxes
may be opened and their interior mechanism examined while the propelled cars or
vehicles are in motion.
9. An electric railway system, provided with a current feeder or main insulated
throughout its length; exposed sectional trolley conductors located in the
surface of the road-bed and operatively connected with electro-magnetic switching
devices located in switch boxes outside of the lines of tram rails, said switch boxes
being provided with means of access whereby their interior structure may be
examined during traffic.
10. An electric railway system provided with a current feeder or main insulated
throughout its length; a series of exposed sectional trolley conductors located in
the road-bed and operatively connected to the current feeder or main through
switching devices located in switch boxes outside of both lines of tram rails,
said switch boxes being pivotally secured in protecting casings and adapted to be
rotated into exposed positions so that they may be opened without interfering with
traffic.
11. In an electric railway system a current feeder or main insulated throughout
its length, in combination with sectional trolley conductors operatively connected
through switching mechanism adapted to connect them in sequence to the current
feeder or main, said sectional trolley conductors being embedded in the road-bed in
a groove slightly below the surface thereof.
.
12, A conducting contact brush pivotally secured to a pair of links or arms
which in turn are pivoted to a fixed support.
13. A conducting contact brush pivotally secured to a pair of links or arms
which in tura are pivoted to a fixed support, in combination with means for lifting
the brush and its support bodily.
14. A contact brush made of a series of wires attached to a support which is

page_text: pivoted to a pair of links or arms secured by pivots to a fixed support, in combination
with means for lifting the brush and its support bodily.
15. A conducting contact brush consisting of a series of wires united to a head
which is sustained by a support pivoted to a pair of links or arms, said links or
arms being in turn pivoted to a fixed support.
16. An electric railway provided with a system of exposed sectional trolley
conductors, in combination with means for preventing current leakage between
active or live trolley conductors made active during the passage of the car or
vehicle and the adjacent sections of such trolley conductors.
17. An electric railway system provided with a series of sectional trolley
conductors cach normally operatively connected through a high resistance earth or
return circuit in combination with means for rupturing said earth or return circuits
in sequence as said trolley conductors are made alive or active on the passage of a
car or vehicle.
18. In an electric railway system an insulated feeder or main; a series of short
sectional trolley conductors provided with means for automatically connecting them
to said current feeder or main in sequence, each of said sectional trolley conductors
being normally connected to an earth or return circuit, in combination with means
for automatically rupturing each return circuit at the instant that it is connected to
the feeder or main.
19. An electric railway system provided with an insulated current feeder or
main; a series of exposed sectional trolley conductors each normally connected
through a high resistance circuit to a return circuit, in combination with means for
automatically connecting said sectional trolley conductors in sequence to the current
main, and additional means for simultaneously automatically rupturing the high
resistance return circuits.
20. An electric railway system embracing an insulated current feeder or main
and two sets of exposed sectional trolley conductors, the first set being provided
with normally closed earth or return circuits and the second set operatively
connected with electro-magnetic mechanism adapted to connect the first set to the
current feeder or main in sequence and to simultaneously disconnect the earth
circuits.
21. An electric railway system comprising an insulated current feeder or main
and two sets of exposed sectional trolley conductors, one set of such conductors
being provided with earth or return circuit connections and the other with circuit
connections to electro-magnets provided with means for connecting the first set to
the current feeder or main in sequence, and additional means for rupturing the
earth or return circuits in sequence, in combination with a leak circuit located
between said sectional trolley conductors for preventing the accidental operation of
any of the switching magnets.
22. An electric railway system provided with an insulated current main and a
series of exposed sectional trolley conductors having means for connecting them to
the current main in sequence, each of said sectional trolley conductors being
provided with a leak circuit for preventing accidents due to any accidental charge
thereof.
23. A conducting contact brush having length sufficient to bridge the space
between two adjacent lines of sectional conductors, in combination with means for
lifting both ends of the brush simultaneously.
24. A conducting contact brush adapted to bear upon two separated sectional
conductors simultaneously, in combination with pivoted means of support adapted
to maintain the brush in parallel positions at different heights.
25. The described method of preventing accidents to persons or animals_on
making contact with live or charged trolley conductors which consists in affording
a path for the charging current which shall be of lower resistance than that offered
by the person or animal making such contact.
26. The described method of preventing accidental circuit connection between

page_text: any one of a series of sectional trolley conductors and a current feeder or main due
to a leak or derived current flow from the main current supply consisting in
shunting said leak around the switch actuating magnets.
27. An electric railway system provided with an insulated current feeder or
main, two sets of exposed sectional trolley conductors, electro-magnets switching
devices for connecting said sectional trolley conductors to the current main in
sequence, leak circuits connected one to each of the working sectional trolley
conductors to and through additional coils of the electro-magnetic switching
devices.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.