US771996A - Measured-service system for telephone-exchanges. - Google Patents

Description

No. 771,996. PATENTED OOTfll, 1904.

F. R. McBERTY & J. L. MOQUARRIE.

MEASURED SERVICE SYSTEM FOR TELEPHONE EXCHANGES.

APPLICATION FILED FEB.23;1904.

No. 771,996. E PATENT-ED 001'. 11, 1904.

V F. MoBERTY E J. L. MoQUARRIB'. MEASURED SERVICE SYSTEM FOR TELEPHONE EXCHANGES.

APPLICATION FILED T11R23. 1904.

4 SHEETS-SHEET 2.

' N0 IODEL.

Zeus/255%? Mv m R 00 A W H NW MC s F WWH mw U N T N A w 8 FA, E IH R BY PULLING CRANK LEVERCLEAPDOWN I No. 771,996. PATENTED 0ST. 11, 1904.

F. R. MGBBRTY & J. L. MOQUARRIE- MEASURED SERVICE SYSTEM FOR TELEPHONE EXCHANGES.

APPLICATION FILED FEB. 23. 1904.

4 SHEETS-SHEET 3.

N0 MODEL.

Mags

No. 771,996. PATENTED OCT. 11, 1904. F. R. McBBRTY & J. L. MOQUARRIE. MEASURED SERVICE SYSTEM FOR TELEPHONE'EXGHANGES.

APPLICATION FILED FEB. 23. 1904.

4 SHEETS-SHEET 4.

NO MODEL.

UG/ZZETS UNITED STATES Patented October 11, 1904.

PATENT OFFICE.

FRANK R. McBERTY, OF EVANSTON, ILLINOIS, AND JAMES L. McQUAR-RIE, OF SOUTH ORANGE, NEW JERSEY, ASSIGNORS TO WESTERN ELECTRIC COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

MEASURED-SERVICE SYSTEM FOR TELEPHONE-EXCHANGES.

SPECIFICATION forming part of Letters Patent No. 771,996, dated October 11, 1904.

Application fil d February 28,1904. Serial No. 194,832. (No model.)

To all whom it 777/601] concern.-

Be it known that we, FRANK R. MoBER'rY, residing at Evanston, in the county of Cook and State of Illinois, and J AMES L. MOQUAR- RIE, residing at South Orange, in the county of Essex and State of New Jersey, citizens of the United States, have invented a certain new and useful Improvement in Measured-Service Systems for Telephone-Exchanges, of which the following is a full, clear, concise, and exact description.

Our invention relates to service-meter apparatus for telephone-exchange systems, and has for its object to provide an improved organization of circuits and apparatus for recording each call from a subscribers station which is answered and the desired connection established by the central-ofiice operator.

In exchanges where the number of calls from a given station determines the amount to be paid for telephone service the system may be operated upon either of two plans: The subscriber may pay for each call as he makes it by actually depositing a coin in a coin-collector, or the call may be recorded upon a register or meter and payment made at intervals in a lump sum for the number of calls recorded. It frequently happens that some lines in an exchange will be equipped with call-recording devices, while others will have the coin-collectors, and still others may have no toll devices at all, the charge being merely a flat rate irrespeetiveof the number of calls. It may even happen that a single partyline will have some of its substations equipped with coin-collectors and other substations of the same line equipped with service-meters. Lines of such differing character are frequently grouped together indiscriminately at the central-ofiice switchboard, and the operator, Who must do the Work of establishing and taking down connections almost mechanically, should not be burdened with the mental effort of distinguishing between these lines or manipulating her apparatus in any different manner in connecting lines of either type. In other words, the supervisory apparatus of the operator and her work in establishing and supervising connections should be the same irrespective of Whether the toll mechanism of the substation be of one type or the other.

In a well-known system where coin-collectors are employed the subscriber in order to signal the central ofiice is compelled to make a preliminary or provisional deposit of a coin in the toll-box. The deposited coin is held pending its final disposition in a temporary receiver, from which it may be discharged either into a cash-box or into a return-chute which refunds it to the depositor.

In another application, Serial No. 140,266, filed January 23, 1903, we have described a system in which the refunding mechanism is manually operated by the subscriber, under the control, however, of the operator at the central oifice, the permanent deposit of the coin in the cash-box being brought about by electromagnetic mechanism controlled by the central-oflice operator.

Our present invention is directed toward the provision of a service-meter which will handle the charge, so to speak, in the same manner that a coin-collector of the above-described type would deal with the coin, according to the varying conditions that may arise, and which may be used in harmony with the coin-collector without making any difference from the operators standpoint.

Certain specially-desired features of opera tion which are accomplished by means of our invention are as follows: A preliminary or provisional charge is made by the mere act of sending in a call if the line is not already busy; but if the line is a party-line and is already in use at some other station the service-meter of the subscriber making the call on the already busy line will not be affected. If the line is out of order or if for any other reason the attention of the central-ofiice operator is not secured, the provisional I charge made in transmitting the call can be rebated by the subscriber. As soon as the operatoranswers the call, however, she immediately has entire control of the service-meter apparatus, so that the subscriber cannot rebate without her cooperation. The final actuation of the service-meter mechanism to complete the registration or under proper circumstances to rebate the charge may be brought about under the control of the central-ofiice operator after the subscriber has given a disconnect-signal by hanging up his telephone. The actuating-magnet of the service-meter is normally disconnected from the line; but its circuit is arranged to be completed by the telephone-switch when the receiver is taken from the hook in transmitting a call. At the same time a locking-circuit of the magnet is established by its own relay-contacts independent of the telephone-switch. The provisional-charge device is actuated in the initial response of the magnet, and the subscriber is provided with a rebate-lever by which the charge device may be restored, the actuation of the rebate-lever also serving to move a switch which breaks the locking-circuit of the magnet and restores the normal condition of the apparatus. The system is so organized, however, that as soon as the operator answers the call the subscribers rebate mechanism is rendered ineffective to restore the provisionalcharge device or to break the locking-circuit of the magnet. The service-meter is therefore under the control of the subscriber until the operator answers the call and after that is under the control of the operator. The provisional-charge device and the means for rebating this charge serve as an inducement to the subscriber to operate the switch which restores the normal disconnection of the service-meter magnet in case the desired connection is not obtained.

We will describe our invention more particularly by reference to the accompanying drawings, in which- Figure 1 is a diagram illustrating a party telephone-line extending from four substations to a central ofiice, together with a portion of the central-office apparatus, the system being organized and equipped for measured service according to our plan. Fig. 2is a View in elevation of the exterior of the sub seribers service -meter. Fig. 3 is a detail perspective view of the principal parts of the mechanism of the service-meter. Fig. 4 is a front elevation of the mechanism of the service-meter, the outside cover being removed. Fig. 5 is a rear view of the mechanism shown in Fig. 4. Fig. 6 is a sectional plan view on line 6 6 of Fig. 4:. Fig. 7 is a view in elevation looking at the right-hand end in Fig. 4, showing the armature of the service-meter magnet fully attracted. Fig. 8 is a vertical sectional view on line 8 8 of Fig. L. Fig. 9 is a vertical sectional view on line 9 9 of Fig. 4. Fig. 10 is a vertical sectional view on line 10 10 of Fig. 4, some of the parts behind be ing omitted for clearness and the parts illustrated in the positions they would occupy when the magnet is initially excited and attracts its armature the first step; and Fig. 11

is a view similar to Fig. 10, but showing the rebate-lever pulled down.

The same characters of reference are used to designate the same parts wherever they are shown.

The telephone-line illustrated in Fig. 1 is a metallic-circuit party-line extending in two limbs 1 2 from the central oifice to four stations S S S. At the central ofiice the limb 1 of the line is normally connected through a line-signal magnet a with the free pole of a grounded central battery 5, the other limb of the line being normally open. The operators circuit 3 4 at the central office may be connected with the line by means of a connection-switch, which is shown as the usual plug and spring-jack. The normal connection of the battery and line-signal with the line is adapted to be broken at the contacts of a cutoff relay 6 when connection is made with the line, the local circuit 5 of the cut-off relay being completed in registering contacts of the plug and spring-jack switch. The central battery 6 is connected in a bridge of the operators plug circuit, so that when the spring-jack of any line is plugged into the battery is connected with the limb 2 and at the same time the normal connection of the free pole with the limb 1 is cut off. The plug and spring-jack switch, in other words, reverses the application of the battery. The operators plug-circuit is of the usual type in which supervisory relays controlling subsidiary lamp-signals are included in one of the link conductors between the free pole of the battery and the ring contacts of the two plugs, respectively, to respond to the substationswitches of the lines with which said plugs may be connected. The answering side of the plug-circuit is also equipped witha switch j, which is adapted when actuated to break both sides of the plug-circuit and connect the ends thereof leading to the answering-plug with the free pole of a grounded generator G. The generator Gr supplies high-potential current-say one hundred and ten voltsand the key f controlling it is the toll-key by which the operator may control the subscribers toll device.

At the substation each subscriber is provided with the usual telephone transmitting and receiving apparatus, with a telephone' switch it controlling the connection of said apparatus with the circuit of the line. The apparatus of only the substation S is shown in detail; but it is understood that the other stations may be similarly equipped. The usual call-bell is also shown controlled by a relay is, which is included with a condenser in a closed bridge of the line-circuit. In addition to the usual telephone apparatus at the substation aservice-meter is provided having an electromagnet m for actuating the same in a ground branch 5, adapted to be connected to the line conductor 1 through conductors 6 7 The conductor 7 may form a portion of the subscribers telephone-circuit including one winding of the induction-coil and is controlled at the telephone switch-hook it, being disconnected from conductor 6 when the telephone is on the hook. Conductor 6 is further controlled at the normally closed contacts of a test-relay Z. Said test-relay when excited is adapted to break the connection of conductor 6 with conductor 5 and complete an alternative connection with conductor 8, leading to the line conductor 2 and including the subscribers transmitter t. The magnet of the testrelay Z is included in a normally open branch 9 from the line conductor 2, said branch being controlled by an extra switch-contact s of the telephone-switch 72/. The arrangement of the contacts should be such that when the telephone-receiver is taken from the hook the contact s will be first closed to complete the branch 9, including the test-relay Z, and then a moment later as the switch-lever continues to move the other usual contacts of the switchhook will be closed, completing the branch circuit 7 6 5 to earth from the battery side of the line if the test-relay has not been excited. If the line is in use at any of the other stations or if a connection has been made at the central office, the conductor 2, which is normally open, would be connected with battery either by way of the bridge-circuit at the other station of the party-line or directly from the battery in the operators cord circuit. Therefore when the telephone is taken for use at a station of a line which is already busy the test-relay Z will receive current first and will become excited, breaking the connection of conductors 5 and 6-and establishing the alternate bridge-circuit 7 6 8 instead of the branch 7 6 5.

WVe will now proceed to describe the mechanism of the service-meter. The magnet m is of the kind known in the art as a two-step magnetthat is, the armature-lever mechanism is provided with a yielding spring-actuated stop a to be engaged by the armaturelever when the same has been attracted about half way, further movement of the armaturelever being opposed by the increased resistance of the spring-stop. The attractive movement of the armature may thus be divided into two distinct steps according to the strength of the current applied to the magnet, the first movement being caused by a weak excitation, such as would be produced by current from battery 6, and the final step or movement being brought about by a stronger excitation, such as would be produced by current from generator G. The armature-lever m is provided with a pawl 172 which is adapted to actuate a recording-train 0. A full attraction of the armature-lever through both steps is required to advance the registering train. The armature lever is adapted, however, in its initial movement through the first step to bring about the release of a charge-shutter p, which indicates to the subscriber that a provisional charge has been entered. The charge-shutter is pivoted at p and is normally held in its upright po' sition by means of a detent-lever r, which is pivoted at r to the framework of the register andis adapted to be raised by a pin o, carried upon a restoring hook or pawl 41 which is carried by the upper end of the armaturelever. When the armature is attracted the first step, the pin o strikes a beveled cam-surface r of the detent-lever r and raises said lever, thus disengaging its end from the rod p of the shutter 11 and permitting said shutter to fall. A further movement of the armature-lever through the second step brings the hooked end of the restoring-pawl 0 into engagement with said cross-rod p of the shutter, and so causes the shutter to be restored. The pin 4) being drawn beyond the cam-surface r of the detent-lever, said lever is permitted to fall again upon the cross-rod p of the shutter to hold said shutter in its restored position. The shutter 19 may also be restored by means of a manual rebate-lever 20, which is intended to be actuated under proper circumstances by the subscriber. The rebate lever or crank w is attached to a shaft w, which carries the restoring-arm 20 When the rebate lever or crank is pulled clear down from the position shown in Fig. 7, for example, to the position shown in dotted lines in Fig. 11, the restoring-arm w moves around and engages a cross-rod p carried by the shutter 39 below its pivotal axis, whereby the shutter may be restored to its initial position. the rebate mechanism and is adapted when the crank-lever w is pulled down to operate a transfer-switch comprising a switch-springy and two alternate contacts g 3 Normally the switch-spring 3 rests against the contact y; but when the crank-lever is pulled down said switch-spring is moved over by the cam w breaking contact at and making contact at f. Two normally separated contactsprings q q are adapted to be closed together by the shutter 19 in falling, the cross-rod p of said shutter (which is preferably of insulating material) engaging the end of the spring q and forcing it into contact with q. Another pair of contact-springs, .2 .2, is arranged to be closed by an arm on of the armaturelever when the latter is attracted to the first step, these contacts remaining closed as the armature is attracted the second step. The switch-contacts q q and 2 .2 control multiple branches, respectively, of a connection 10 from the branch 5 to the spring y of the transfer-switch. When said spring is in its normal position, if either of said contacts (1 q or 2 z is closed the circuit of branch 10 5 will be completed from one side or the other of the line (depending upon the position of A cam 20 is carried by the shaft w of said transfer-switch) to earth, including the actuating-magnet m of the service-meter.

The operation of the system is as follows: A subscriber desiring an exchange connection transmits a call in the usual manner by removing his telephone from its hook. If the line is already busy at some other station, the test-relay Z will be immediately excited, as before explained, disconnecting the branch 5, containing the service-meter, so that the subscriber will not be charged. If, however, the line is free, the circuit 7 6 5 will be completed and the magnctm of the service-meter will be excited by current from the central battery 6, whereby said magnet will attract its armature the first step. This will serve to release the charge-shutter p, which will drop down to indicateto the subscriber that the charge is provisionally registered. The counting-train, however, will not yet be actuated. The charge-shutter in falling closes contacts 9 (1' together, and the movement of the armature-lever of the magnet will also serve to close contacts .2, whereby the circuit 10 from the transfer switch lever 1 to earth through the magnet m will be completed through both the parallel branches and a locking-circuit for the magnet will exist through said path 10 independent of the telephoneswitch. If, however, the attention of the central office is not secured, the subscriber may restore the normal condition of the apparatus by pulling down his rebate-lever w. This lifts the shutter 29, opening contacts 9 q, and also operates the transfer-switch y, which shifts the connection of the branch containing the magnet to the other line conductor 2, which is normally open. The locking-circuit of the magnet being thus broken, said magnet allows its armature to fall back, opening the contacts 2 z and also permitting the shutter to be latched up by the detent 9*; but as soon as the operator responds to the call in the usual manner by plugging into the springjack of the line the connection of battery 6 with the line is reversed, the free pole of said battery be ing applied to conductor 2 instead of to conductor l. The subscriber is prevented from rebating the charge as long as the connection remains up at the central office. If a rebate is attempted, the movement of the rebate-lever serves simply to transfer the connection of the magnet on from the conductor 1 to the conductor 2, and battery being applied to this conductor 2 at the central office the magnet remains excited and the charge-shutter cannot be latched up. If, however, the operator finds that the desired connection cannot be given, as where the line called for is busy, she will tell the calling subscriber to hang up his telephone and then work the rebate-lever. As soon as the subscriber hangs up his supervisory lamp-lights, according to the wellknown system, which need not be particularly described, and the operator immediately pulls out the plug. The subscriber should now actuate the rebate-lever in order to restore the normal condition of his apparatus, and he is induced to do this by the indication that a provisional charge is registered and may be rebated by actuating the rebate-lever. After the operator has pulled out the plug the line signal-lamp of the subscriber will light, due to the reestablishing of the conditions of a call, and will remain lighted until the subscriber operates his restoring mechanism; but if the desired connection is established the operator will wait until both subscribers have hung up and then will press her toll-key f, which will apply current from the grounded generator G to both sides of the line. This current will pass out over the line and to earth through magnet m at the substation, causing said magnet to attract its armature the full distance, recording the call upon the counting-train 0 and restoring the shutter 12 to its normal position. The subscriber will not be able to prevent the operator from registering by moving his rebate-lever, since this will serve to simply transfer the connection of the magnet from one line conductor. to the other, and since current is applied to both line conductors the magnet will be operated in any case. When the key f is released, current from the generator G is cut off and the battery bagain applied; but the armature of'magnet m in returning from its fully-attracted position to the midway position does not again release the shutter. The reason for this is that the pin 1; in returning rides over the cam-surface r of the detent-lever instead of going under it. The detent-lever is therefore left down in engagement with the cross-rod p of the shutter instead of being lifted to release the shutter. Now when the operator takes out the plug the magnet becomes deenergized and allows its armature to fall clear back. I The pin 4) therefore passes clear over the cam-surface r and drops into its original position ready to be drawn against said camsurface and lift the detent upon the next excitation of the magnet. The pin o thus travels round and round the cam-surface r of the detent-lever, going under said surface to lift the detent-lever when the magnet is attracted and returning over the top of said cam-surface when the magnet is deenergized.

Having thus described our invention, we claim 1. The combination with a metallic-circuit party telephone-line extending from a central office to several substations,of a grounded battery at the central office, the free pole whereof is normally connected to one side of the line, the other side of the line being normally open, a service-meter at one of the substations in a normally open ground branch from the battery side of the line, a test-relay in a normally open ground branch from the other side of the line, the circuit of said servicemeter being controlled in contacts of the testrelay, a bridge-circuit at each substation controlled by the telephone-switch thereat, the bridge-circuit at the station having the service-meter being also controlled at the front contact of said test-relay, and a telephonesWitch adapted when actuated to close first the test-relay branch and then the servicemeter branch; whereby the circuit through the service-meter magnet is not completed if the line is in use at another station.

2. The combination with a telephone-line extending from a substation to a central office, of a service-meter at the substation having a manually-operated rebate-lever, a switch-contact operated in the movement thereof, a rebate-controlling magnet, a connection-switch at the central oflice, and a locking-circuit for said magnet established by said connectionswitch and completed by the rebate-lever contact.

3. The combination with a telephone-line, of a service-meter at the substation having an operating-magnet adapted to be connected with the line, armature-lever mechanism for said magnet adapted for two movements according to the current applied, a manuallyoperated rebate mechanism, means actuated in one movement of the magnet-armature for rendering the rebate mechanism ineffective, a counting-train actuated by said armature-lever mechanism in the other movement thereof, and means at the central office for applying currents to effect said movements.

4. The combination with a telephone-line extending from a substation to a central office, of a grounded battery and a line-signal normally connected with one limb of the line at the central oflice, a telephone-switch at the substation, a service-meter magnet in a normally open ground branch from the battery side of the line controlled by said telephoneswitch, a contact closed by the magnet when excited adapted to complete a locking-circuit through said magnet independent of the telephone-switch, a service-meter, a manuallyoperated rebate mechanism therefor, a switch actuated in the operation of the rebate mechanism for transferring the connection of the service-meter magnet to the other side of the line, means controlled by the magnet for rendering the rebate mechanism ineflective, and a connection-switch at the central ofiice adapted to apply the battery reversely; whereby a rebate is prevented when connection is made with the line.

5. The combination with a metallic-circuit telephone-line and a battery normally connected with one limb thereof at a central oifice, of telephone apparatus and a telephone-switch at a substation of the line, a service-meter at the substation having an actuating-magnet in shutter normally held by a detent, a recording-traima two-step armature for the magnet adapted to move the detent to release the signal-shutter in the first step of its movement and to operate the recording-train and restore said signal-shutter in the second step, a contact actuated in the fall of the shutter closing a branch circuit through the magnet independent of the telephone-switch, a manual lever adapted to return the shutter to its normal position and open said last-mentioned contact, a switch actuated in the movement of said manual lever adapted to transfer the connection of the magnet to the other side of the line, and a switch at the central office adapted to reverse the normal connection of the battery with the line.

6. Thecombination with a party telephoneline, of a service-meter at one of the substations, a telephone-switch controlling the circuit of said meter, whereby the same is actuated in makinga call, a connection-switch at the central office, telephone-switches at the other stations, and means controlled by said connection switch or by the telephoneswitches at the other stations for changing the electrical condition of the line, and a test-magnet controlling the operation of said servicemeter sensitive to such changed condition; whereby no charge is registered if a call is made while a line is already busy.

7. The combination with atelephone-line extending from a substation to a central office, of a service-meter at the substation having an actuating-magnet in a normallyopen branch, a signal device at the central office, a telephone-switch at the substation adapted to close said service-meter branch and thereby complete a circuit for the central-oliice signal, a signal-shutter for the service-meter adapted to be released by said magnet, contacts closed by the signal-shutter completing a circuit of the magnet independent of the telephoneswitch, a rebate-lever, and means for opening the circuit of the magnet in the operation of the rebate-lever.

8. The combination with a subscribers telephone-line extending from a substation to a central oflice, of a service-meter'at the substation having an electromagnet for actuating the same, a circuit for said magnet controlled by a switch at the substation closed in making a call, manually-operated rebating mechanism for the service-meter, an operators connection-switch at the central oflice, and means controlled by said switch for rendering the rebating mechanism ineffective, whereby the subscriber may rebate his service-meter after making a call until the operator answers, the rebating mechanism being thereafter under the control of the operator.

9. The combination with a party telephoneline having toll devices at the substations thereof, an operating-magnet for each toll device in a normally open ground branch, asubstation telephone-switch adapted to close said branch, a locking-circuit for the magnet, and a contact controlling said locking circuit closed in the response of the magnet, a manual switch to be operated by the subscriber adapted to open said locking-circuit, and a charge device for the service-meter set in the response of the magnet and adapted to be restored in the operation of said manual switch.

10. The combination with a metalliccircuit telephone-line extending from a substation to acentral offiee, of a grounded battery having its free pole connected to one limb of the line at a central oifice, a line signal device in said limb, a service-meter magnet in a normally open ground branch from said limb at the substation controlled bya telephone-switch at said station, a contact closed by the magnet when excited adapted to complete the circuit of said branch independent of the telephone switch, a manual rebate lever and a transfer-switch operated thereby adapted to transfer the connection of said branch to the other limb of the line, an operators connection-circuit at the central office, and means associated therewith for applying from a grounded source current to both sides of the line simultaneously, whereby the service-meter magnet is actuated independent of the position of the transfer-switch.

11. The combination with a telephone-line extending from a substation to a central office, of an electromagnetic service-meter at the substation, a part at the substation adapted to be moved manually incident to the use of the line, a switch operated in the movement of said part, a circuit adapted to connect the service-meter with the line, controlled by 'said switch, electromagnetic locking mechanism adapted to maintain the connection of the service-meter with the line independent of said switch, and means controlled by the operator at the central oflice adapted to control said locking mechanism and to apply current to the line to operate said service-meter.

12. The combination with a party telephoneline extending from a telephone set at each of a plurality of substations to a central station, of an electromagnetic service-meter at a substation of the line, a circuit for the servicemeter completed to the line in taking the substation-telephone for use, electromagnetic mechanism adapted to render the service-meter inoperative, an actuating-circuit for said mechanism, and switches one at each of the substations of the line, and one at the central station adapted to control said circuit, said switches being closed in the use of the line at their respective stations, whereby the servicemeter is kept from operative connection with the line when the line is in use at some other station.

13. The combination with a telephone-line extending from a substation to a central office, of a signal and a source of current connected with the line at the central oflice, a switch at the substation adapted to control the circuit of said signal, an electromagnetic service-meter at the substation comprising an electro-' magnet, a two-step armature therefor, and a registering-train actuated in the final step or movement of said armature, acircuit for said magnet completed to the line in the operation of said signal-controlling switch, an alternative circuit for said magnet to the line independent of said switch, a relay-contact adapted to close said circuit in the initial movement of said service-meter armature, a source of current adapted to energize said magnet to cause said service meter to register, and switching means at the central ofiice adapted to apply said current to the line.

14. The combination with a telephone-line extending from a substation to a central office, of an electromagnetic servicemeter at the substation comprising an electromagnet, a two-step armature therefor, and a registeringtrain actuated in the final step or movement of said armature, a switch adapted when actuated to connect the service-meter magnet with the line, a relay-contact closed by said armature in the initial movement thereof, adapted to connect the magnet with the line independent of said switch, a source of current adapted to energize said magnet to cause the operation of said service-meter, and switching means at the central ofiice adapted to apply said current to the line.

In witness whereof we have subscribed our names this 11th day of January, 190 1.

FRANK R. McBERTY. JAMES L. McQUARRIE.

\Vitnesses:

E. R. SKINNER, E. F. BEAUBIEN.

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