US1842805A

US1842805A - Elapsed time metering system

Info

Publication number: US1842805A
Application number: US442829A
Authority: US
Inventors: Norman H Saunders
Original assignee: Associated Electric Laboratories Inc
Current assignee: Associated Electric Laboratories Inc
Priority date: 1930-04-09
Filing date: 1930-04-09
Publication date: 1932-01-26
Anticipated expiration: 1949-01-26

Description

Jan. 26, 1932. N. H. SAUNDERS 1,842,805

ELAPSED TIME METERING SYSTEM Filed April 9, 1930 5 Sheets-Sheet l Nurman EBLITZCZEFS 5 0 Jan. 26, 1932. N. H. SAUNDERS 1,842,805

ELAPSED TIME METERING SYSTEM Filed April 9, 1930 5 Sheets-Sheet 2 s4 lWA/G BA CK TONE ]nuaninr NDFTUEH SEUFZHEPE' Jan. 26, 1932. N, SAUNDERS 1,842,805

ELAPSED TIME METERING SYSTEM Filed April 9, 1930 5 sheets-Sheet 3 o/Ffimlm;

T0 OPEPS TELEPHONE 4 win N urman HSaundsrs Jan. 26, 1932. N. H. SAUNDERS 1,842,805

ELAPSED TIME METERING SYSTEM Filed April 9, 1930 5 Sheets-Sheet 4 7%% Hit Jan. 26, 1932. I SAUNDERS 1,842,805

ELAPSED TIME METERING SYSTEM Filed. April 9, 1950 5 Sheets-Sheet 5 Ln i a MAEG/A/AL k I H I /42 H -Inuaniur' NarmanHSaunders Patented Jan. 26, 1932 UNITED s'rrss PATENT QFFEE NORMAN SAUNDERS, OF I-IOIVIEWQOD, ILLINOIS, ASSIGIQ'OR, BY MESNE ASSIGNMENTS, TO ASSOCIATED ELECTRIC LABORATORIES, TING, OF OHICAGG, ELLINOIS, A CORPORA TION OF DELAWARE ELAPSED TIME METERING SYSTEM Application filed April 9,

The present invention relates to elapsed time metering in general, but is concerned more particularly with elapsed time metering semi-automatic telephone systems, in which calls are extended through the medium of automatic switches controlled from an operators position.

The principal object of this invention, briefly stated, is the provision of new and improved circuit arrangements whereby a calling subscriber may be charged for all calls, regardless of whether or not those calls are completed, according to the time the call-- ing subscribers receiver is off of the receiver hook, the charge being assessed at intervals durin that time.

A Ieature of the system, provided in accordance with said principal'object, is an arrangement whereby, when a busy condition is encountered at any time during the establishment of the connection, a busy signal is transmitted from the trunk equipment associated with the first switch of the switch train, and whereby all of the switches succeeding the trunk equipment are released for use of other calling subscribers.

Another feature is the arrangement whereby the operators impulse sender is released, when a busy condition is encountered, without it being necessary for that sender to complete the sending of the remaining digits.

Other objects and features having to do with the refinement of the various circuits peculiar to a system of this character but not being specifically pointed out now, will be readily apparent from a perusal of the description to follow, reference being had to the accompanying drawings comprising Figs. 1 to 5, inclusive, which, when arranged with Fig. 2 to the right of Fig. 1, Fig. 3 directly below Fig. 1, and Figs. 4 and 5 to the right of Fig. 8, show by means of the usual circuit diagrams suflicient of the apparatus employed in a system embodying the principles of the invention to enable a complete understanding thereof to be had.

General description The equipment shown in Fig. 1 includes the subscribers station A, the line of Wl11Cl1 1930. Serial No. 442,829.

terminates at the exchange in the automatic lineswitch G which has access to trunks among which is the trunk comprising conductors 1 to 3, inclusive. Individual to this trunk is a trunk relay group RG and a selector switch D, and it is through this trunk relay group that connection is established between the calling subscriberand the operator, and through which the operators sending equipment operates the selector D to ext id the connection. It is through the relay group HG that the calling subscribers elapsed time meter M is operated when connection is made with the trunk 13 by the subscribers lineswitch C.

Thelineswitch C is mechanically of the well known rotary type in which the wipers have no normal position, remain in thelast position in which they were last used, and move in a forward direction only.

The meter M may be considered as representing any of the well known devices whereby the reversal of current through a magnet results in the operation of a registering means. A meter of this type is shown in United States Letters Patent, No. 912,268, issued to Charles M. Beattie, under date of February 9th, 1909.

The selector D is mechanically of the well known vertical and rotary type in which the bank contacts are arranged in horizontal rows or levels accessible to the switch wipers which are carried by the switch shaft, which shaft is elevated in a step-by-step motion in accordance with the impulses received by the selector to position the wipers opposite the corresponding level, and which is then automatically rotated to position the wipers in engagement with a set of contacts in that level associated with an idle trunk leading to the next switch in the train.

Associated with the trunk relay group HG is a sender-selector switch SS, the function of which is to select an idle operators impulse sender and associate .that sender and the operators .telephone equipment with the trunk 13.

The apparatus shown in :Fig. 2 of the drawings is the connector E and the ringing frequency selector RFS. This connector E is mechanically the same as the selector D, Fig. 1, except that the switch shaft is directively controlled in its rotary motion, that is, is rotated a number of steps in accordance with the second series of impulses received by the connector. The connector E by being provided with the ringing frequency selector RFS is adapted for use in telephone systems having ten-party lines.

The ringing frequency selector RFS is mechanically of the well known rotary type of switch whose wipers have a normal position and are advanced therefrom in a stepby-step motion by the operating magnet 79. The operation of the release magnet 80 causes the wipers to return to their normal positions.

The apparatus represented by the rectangle P, Fig. 1, and the rectangle P1, Fig. 2, may each be considered as a continuously operating device by means of which the polarity of the two associated conductors is reversed at predetermined intervals. As will be more clearly explained hereinafter, the said conductors serve as a source of battery feed for the calling line and in order that there need be no interruptions of the undulatory voice currents which may be traversing the line, the apparatus is arranged to gradually decrease the potential and subsequently increase it gradually to the maximum voltage. A device of this kind is shown in the aforementioned Beattie patent.

The apparatus shown in Figs. 3, 4 and 5 includes the operators sender-control key set and associated relays, and one of four senders. The portion of the sender shown in Fig. 3 includes the relays 111 to 114, in elusive. The registering portion of the sender is shown in Fig. 4, while the sending portion is shown in Fig. 5.

The layout of the apparatus is such that each semi-automatic operators position is provided with four senders similar to that shown in the drawings. The sender-selector SS, Fig. 2, which is usually a 25 position mechanism, has access to senders of several operators positions.

- Although the system as shown in the drawings involves the use of only a first selector and a connector, second and even third selectors may be placed between the selector D and the connector E. In that case, selectors like selector D will be employed.

Detailed description The apparatus having been described generally in this manner, it will now be described in detail as to its operation. For this purpose, it will be assumed that the subscriber at substation A, Fig. 1, desires a connection to be set up from his line to the line of another subscriber, whose number is, for example, 7945, it being remembered that this subscriber is one of ten subscribers who are on the desired line and whose telephone numbers differ only in the last digit which is the ringing-code selecting digit.

When the receiver is removed from the receiver hook at station A, the lineswitch C, the circuits of which are not shown, operates in the usual manner to select an idle trunk,

which trunk, it will be assumed, is the one comprising conductors 13. WVhen this trunk is seized, battery feed relay 8 of the trunk relay group RG operates over the calling line and at its armature 9 completes the obvious circuit for slow-to-release relay 10. Relay 10 operates when its circuit is closed and at its armature 11 connects ground to the release trunk conductor 3, so as to guard the trunk line from intrusion and to main tain the lineswitch C operated, and at its armatures 12 and 13 connects the test wiper of the sender selector SS to the motor magnet MM thereof.

The connection of ground to the releasetrunk conductor 3 completes the circuit of relay 17 by way of armature 15 and resting contact of relay 14, lower winding of relay 17, armature 13 and make contact of relay 10, interrupter springs of motor magnet MM, and winding thereof to battery. However, if the wipers of the sender selector SS are in engagement with contacts associated with a busy sender, ground will be present on the contacts with which the test wiper is in engagement. This ground will short circuit relay 17 before it has had a chance to operate, and will supply direct ground to the motor magnet MM through the interrupter springs thereof.

Sender selection When direct ground is so fed to the motor magnet MM of the sender selector SS, the motor magnet will operate and advance its wipers into engagement with the next set of contacts of its bank. If the sender associated with this set of contacts is also busy, the test wiper will again encounter ground and the motor magnet will again operate to advance the sender selector wipers into engagement with the next set of bank contacts. This action will continue until the test wiper engages a contact to which no ground is connected.

Assuming that the trunk line comprising conductors 24 to 28, inclusive, and extending to the sender shown in Figs. 3, 4 and 5, is the one found to be idle, switching relay 17, which is short-circuited as long as ground potential is encountered by the test wiper of the sender selector SS, energizes in series with the motor magnet MM. The motor magnet, because of the relatively high resistance of relay 17, does not operatively energize in series therewith.

At

armatures

18 and 22, relay 17 when so energized connects the talk and -l-talk wipers, respectively, of the sender selector SS to the negative and positive conductors 1 and 2 of the trunk line, thereby extending those conductors into connection with the negative conductor 24 and the positive conductor 25 extending to the selected sender. At armature 19, relay 1.7 connects the switch ing conductor and the switch wiper to the winding of relay 4. At armature 20, relay 17 disconnects the test wiper from the junction of the winding of relay 1'? and the motor magnet MM, and connects the wiper to ground, therebv placing a guarding and holding potential upon conductor 26. At armature 21, relay 1'? connects its upper lowresistance winding in series with its lower high-resistance winding to insure its being held perated. At its armature 23 relay 1'? connects the impulse conductor 28 through the impulse wiper of the sender selector SS, t0 the positive line conductor of the selector D.

In the selected sender, relay 111 operates over the grounded release trunk conductor 26, and through contacts of relay 112, and at its lower armature disconnects the corresponding test conductor from ground and ex tends it to the #1 sender connecting relay 108. This is preparatory to enabling the dis tributo-r switch DS to stop on a contact associated with the #1 sender and operate the #1 connecting relay 108, so as to connect the #1 sender with the operators equipment. At its upper armature, relay 111 places ground upon the associated start-operating slow-acting relay 116 through contacts of relays 105-108. Relay 116 closes a circuit for the associated relay 115, which relay operates and starts the hunting action of the distributor switch DS by connecting the test wiper 125 to stepping magnet 12 1 through the self-interrupting contacts of the stepping magnet. At its two upper armatures, relay 115 disconnects common conductors 118 and 119 from the operators telephone set and connects the conductor 119 through the associated condenser to the differential tonegenerating relay 110.

Each time relay 110 pulls up and closes the circuit for its upper winding in parallel with its lower winding, it falls back due to the differential relation between its two windings, thereby generating a tone current which is impressed upon conductor 119 through the associated condenser. This tone current is not sent back to the calling line for the time being.

The test wiper 125 of the distributor switch DS encounters ground potential on the test contacts of each sender not in calling condition owing to the fact that the relay corresponding to relay 111 in each sender not in a calling condition is deenergized and has a ground potential placed upon the corresponding test conductor at its lower armature.

When the wiper 125 of the distributor switch DS arrives on a contact associated with the calling sender, the first contact or the fifth contact, the stepping operation ceases due to the absence of a direct ground potential on the test conductor. A circuit is then closed for relay 108 through the test wiper 125 and the lower armature of relay 111 from battery through stepping magnet 12 1v and the lower contacts of relay 115. Magnet 121 does not operatively energize in series with relay 108 owing to the relatively high resistance of the latter. When relay 108 operates, it connects, at certain of its lower armatures, the six conductors associated with the operators key-set, to the corresponding conductors of the sender; it closes a locking circuit for itself at its inner lower armature in multiple with the lower contacts of relay 115; it lights the call lamp associated with the operators key-set at its upper armature; it connects up the conductors 2 1 and at its intermediate upper armatures to the common conductors 118 and 119; and at its innermost upper armature it opens the circuit of slow-acting relay 116.

During the time required for relay 116 to fall back after its circuit is opened, the tone generated by the differential tone-relay 110 is heard by the calling subscriber who is informed thereby that he may now give the desired number to the operator.

Relay 116 falls back shortly and opens the circuit of relay 115 in addition to stopping the generating of tone current, whereupon relay 115 falls back and connects conductors 118 and 119 to the operators telephone set. At the time this connection is made, the operators telephone set is shortcircuit-ed by contacts of relay 109, which relay was cnergized through make contacts of relay 115, so that the charge on the associated talking condenser is equalized with the potential difierence across conductors 118 and 119 in order to shield the operator from disagreeable noises in her head set. Relay 109 falls back an instant later and places the operators telephone set in communicative connection with the calling subscriber.

Registration of desired number Upon hearing the number desired by the calling subscriber, which number, as hereinbetore assumed is 7945, the operator depresses the digit keys of her key-set correspon ding to the respective digits of the number. It will be noted that the four conductors associated with the digit keys are designated A, B, C and D. The operation of a given digit key results in the grounding of one or more of these conductors. As can be seen in reading the drawings, the conductors grounded responsive to the operation of each key have been noted in parentheses above each key.

WVhen the operator depresses the #7 key, the A conductor is grounded, operating relay A1 of the thousands register TH, Fig. 4, relay 127 being operated at this time from the grounded release trunk conductor 26 through contact and armature of release relay 114 and the inner upper contacts of the transfer relay 126. Upon operating, relay A1 locks itself to conductor 123 through transfer relay 126, but relay 126 does not opcrate until the initial circuit of relay A1 is opened, being short-circuited until this opening occurs when the digit key #7 is released.

hen the #7 key is released, relay 126 operates in series with relay A1 (which latter relay remains operated) and at its inner upper armature disconnects the connecting relay 127, whereupon relays A1D1 are disconnected from the conductors A to D. At its uppermost armature, relay 126 places ground upon conductor 122 through contacts of relay 129, operating relay 113, Fig. 3, to open a point in the switch-through circuit to be hereinafter described and to place a multiple ground connection on release trunk conductor 26 by way of conductor 26. At its middle upper armature, relay 126 extends a ground potential to the relays of the hundreds register H, operating relay 131 to connect the conductors A, B, C and D to the relays A2, B2, C2 and D2, respectively.

Now, when the operator depresses the #9 key to register the hundreds digit 9, conduc tor C is grounded, operating relay C2. This relay locks up in series with relay 130 which remains short-circurted as long as the key is depressed and operates as soon as the key is released. Relay 130, in addition to extending a ground potential to the tens register T to cause relay 135 to operate, disconnects relay 131 and places a further multiple ground connection upon conductor 122.

When the tens digit 4 is registered by depression of the #4 key, relays B3 and C3 are operated over conductors B and C, whereupon they look up in series with relay 134, which relay operates when the key is released and transfers the control to the units register U by releasing relay 135 and operating relay 139. A further multiple ground connection is made to conductor 122 at the upper armature of relay 134-.

When the units digit 5 is registered by the depression of the #5 key, relays B4 and D4 operate over conductors B and D and lock up in series with relay 138, which operates when the key is released to open the circuit of relay 139 and place a still further multiple ground connection upon conductor 122.

Transmission of numbers Having finished setting up the number, the operator depresses the St-art key, Fig. 3,

whereupon start relay 112 is operated through contacts of relay 108 and through the lower winding of relay 111. Relay 112 closes a locking circuit for itself to conductor 26 at its inner-upper armature, at the same time disconnecting the upper winding of relay 111 from conductor 26. However, relay 111 remains operated through its lower winding until the start key is released, whereupon it falls back and opens the circuit of relay 108, at the same time replacing ground on the associated contacts in the bank of wiper 125 of the distributor switch DS. Relay 108 falls back and disconnects wiper 125 from the associated operating magnet, at the same time severing all connections between the operators common equipment and the sender #1 and closing the associated point in the chain circuit of startrelay 116, so as to enable the distributor switch DS to operate again to connect the operators head set to another sender which may have been taken for use in the meantime.

As a result of the operation of start relay 112, the switch-through circuit to be hereinafter described is prepared at the upper armaears of relay 112, and at the middle armature thereof ground is placed from the inner contacts of relay 113 upon the start conductor 121 in order to start the stepping action of the counting switch CS, Fig. 5, under the con trol of the marginal relay 142 associated with the interrupter I.

It may be pointed out at this time that the inte *rupter 1 is first started into operation upon the seizure of the sender when the ground potential is placed upon release conductor 26 and consequently upon the conductor 26'. This results in a closure of a circuit through the magnet Winding of the in terrupter I and through the marginal stepping relay 142 in series. Relay 142 does not operate in series with the magnet winding of the interrupter I. But, upon the energization of this magnet winding, the weighted pendulum is drawn over to the right, short circuiting the magnet winding of the interrupter, whereupon the interrupter magnet deenergizes and the stepping relay 142 energizes. When the pendulum swings to the left, it again includes the magnet winding of the interrupter in circuit, whereupon relay 142 falls back. As the interrupter I continues to operate, the marginal impulse relay 142 is operated each time the pendulum swings to the right, and the interrupter contacts of the interrupter I are opened each time the pendulum swings to the left.

However, the operation of the interrupter I is ineffective and the operation of the stepping relay 142 is ineffective likewise until start conductor 121 is grounded, as before described, upon the depression of the start key by the operator, from which time each deenergization of the stepping relay 142 results in an operation of the operating magnet of the counting switch OS from conductor 121 through contacts of stop relay 144. The wipers 145 and 146 of the counting switch CS are advanced only upon the back stroke of the operating magnet, and they consequently remain in the position shown upon the first energization of the magnet. When the pendulum of the interrupter I swings to the right and opens the operating magnet circuit by energizing stepping relay 142, the operating magnet of the counting switch OS falls back and advances the wipers 145 and 146 one step, whereupon pick-up wiper 145 encounters a grounded contact, closing a circuit for pick-up relay 143. Pick-up relay 143 op crates and prepares a locking circuit for stop relay 144 at its lower armature; places a further multiple ground connection upon conductor 122 at its upper amature; and at its inner-upper armature it removes one ground connection from the outgoing impulse conductor 28, leaving the conductor grounded only through the contacts of the interrupter I. Now, with the circuit in this condition, each time the pendulum of the interrupter I swings to the left, it sends an impulse by removing ground from conductor 28 to deenergize the line relay of the selector D, Fig. 1. The operating magnet of the counting switch CS is reoperated by the deenergization of the stepping relay 142, so that each time the pendulum swings to the right relay 142 reoperates and drops back the operating magnet to advance wipers 145 and 146 another step.

hen the wipers of the counting switch are advanced again at the end of the transmission of the impulse, wiper 146 encounters the bank contacts in which the first stop conductor terminates, which stop conductor is grounded only in case the digit being transmitted is the digit 1. The digit being transmitted in this case is the digit 7, stored on the thousands register TH, Fig. 4, from which it follows that the #7 conductor is grounded instead of the :ttl conductor. The #7 conductor is grounded at this time through the lower armature and resting contact of transfer relay 129, Fig. 4, right-hand armature and make contact of relay A1, inner-righthand armature and resting contact of relay B2, inner armature and resting contact of relay C1, and inner armature and resting contact of relay D1. That being the case, the sending operation continues and the advance of the counting switch CS continues until seven impulses have been sent by the interrupter I over the outgoing impulse conductor 28. At the end of the seventh impulse,

' wipers 145 and 146 are advanced again and 7 the lower contacts of relay 143; closes a reground connection upon conduct-or 122 at still another armature; and at its uppermost armature it disconnects the operating magnet of the counting switch CS from the impulse circuit controlled by the stepping relay 142.

Responsive to the closure of the restoring circuit of the counting switch CS at the inner upper contacts of relay 144, the self-interrupting operating magnet of the counting switch operates rapidly in a buzzer-iike manner and the wipers 145 and 146 are advanced until they stand in the position shown in the drawings, whereupon the action ceases due to the fact that the normal contact in the bank of wiper 145 is ungrounded. At this time, the circuit of the slow-acting pick-up relay 143 is opened, with the result that the relay falls back shortly and opens the locking circuit of relay 144, which relay shortly falls back to start the transmission of the hundreds digit 9.

Vhen the circuit of stop relay 144 is closed to end the transmission of the thousands digit, a parallel circuit is closed over conductor 120 and through contacts of relay 129 for relay 128, Fig. 4. Relay 128 operates and locks itself to conductor 123 in series with relay 129, which latter relay remains shortcircuited until the locking circuit of relay 144 is opened by relay 143, whereupon relay 129 energizes in series with relay 128 and transfers the conductor 120 to relay 132 of the hundreds register H.

The sendin operation proceeds for the second digit in the same manner as described in connection with the first digit and is terminated at the end of the transmission of nine impulses upon the cnergization of stop relay 144 when wiper 146 encounters the bank contact in which the stop conductor #9 terminates. The stop conductor #9 is grounded at this time through the lower armature and make contact of relay 129, through the lower armature and resting contact of relay 133, through the right-hand armature and resting contact of relay A2, through the outer-right-hand armature and resting contact of relay B2, through the outer-right-hand armature and make contact of relay C2, and then through the third righthand armature and resting contact of relay D2.

Relay 132 is energized at this time in multiple with the stop relay 144 and locks itself in series with relay 133, which latter relay operates, when the circuit of the stop relay 144 is opened, and transfers conductor 120 to relay 136 of the tens register T. The stopping grouud potential is shifted at the lower ace terminates.

contacts of relay 133 to the register relay of he tens register.

lVhen the transmission of the tens digit takes place, the operation is the same as described hereinbefore until stop relay 14% operates at the end of the fourth interruption in the outgoing control circuit when wiper 1 16 of the counting switch CS encounters the bank contact in which stop conductor 1 Stop conductor is grounded, at this time, through the armature and resting contact oi relay A3 and the armatures and make contacts of the operated relays B3 and C3 of the tens register. Relays 136 and 13'! are operated in a manner similar to relays 132 and 133 to transfer the control to the units register U.

The transmission of the units digit next takes place and is terminated upon the energization of stop relay 14 1 at the end of th fifth interruption in the outgoing impulse conductor 28 when wiper 146 engages the bank contact in which stop conductor #5 terminates, stop conductor #5 being grounded at this time through contacts of the nonoperated relays A and C4 and the operated relay B 1 and De.

Freeing the sender It will be noted that each of the

relays

129, 133, 13'? and 1 11, upon operating, removes ground at one point from the multiplygrounded conductor 122. Now, when rela 1 1-1-1 operates upon the opening of the circuit of slow-acting stop relay 144, when pick-up by removing ground from conductor 26 at one point, and closes the switch-through circuit through contacts of the operated relay 112 and over conductor 27. This circuit includes the switch wiper of the sender selector SS, Fig. 1, armature 19 and make contact of relay 17, and the winding of switch through relay 1. Relay 4 operates and locks itself to release trunk conductor 3 at its armature 5 and make contact, and at armatures 6 and 7, it disconnects the incom. g trunk conductors 1 and 2 from the wind; ofthe battery feed elay 8 and extends th n to the corresponding conductors of the connection established through the selector D. As a result of this, battery teed relay 8 falls ark and is followed by the falling back f relay '10 and consequently relay 1'? to disconnect the wipers of the sender selector SS to free the sender. The established connection is now held up over the line of the substation 11.

The falling back of relay 17 results in the removal of groundfrom the release trunk conductor 26. This results inthe deenergization of relay 112, Fig. 3, which is locked up to conductor 26 and the deenergization of

relays

126, 128 and 129, Fig. 4, which are locked up to conductor 26 over conductor 123 ant through the armature and resting contact of relay 11 1. As a result of the deenergization of relay 126, relays 130, 132 and 133 of the hundreds register H dcenergize and in turn cause the deenergization of the relays 132, 136 and 137 of the tens register T, which is followed by the deenergization of

relays

138, 140 and 1 11 of the units register U. The operation of the interrupter I ceases as a result of the removal of ground potential from conductor 26.

The sender is now at normal and may be seized again for use in another call.

Selector operafion The operation of the automatic switches employed in establishing the connection in response to the trains of impulses transmitted by the sender over conductor 28 will now be described by first detailing the operation of the selector D in response to the first im pulse train. Returning now to the point in the description where the relay 17 first operated to connect up the wipers of the sender selector SS, it will be noted that the connection of the impulsing wiper at armature 2 tothe positive talking conductor connects ground thereto since conductor 28 is grounded through resting contact and armature of relay 143, Fig. 5. This ground is connected to the winding'of line relay 30 of selector D, by way ofarmature and resting contact of switching relay 11 of the selector. This results in the operation of the line relay and the completion of the circuit of release relay 31 from ground by way of armature 1 1 and resting contact of switching relay 41 through armature and make contact of line relay 30. Release relay 31 operates, at its armature 32, connects ground to the release trunk conductor 3 and, at its armature 33, opens the release magnet circuit and prepares the impulsing circuit for the vertical magnet through the series relay 34:.

Each subsequent removal of ground from conductor 28 by the interrupter I, Fig. 5, as has been explained, results in the deenergization of relay 30 and since, in the assumed case, there are seven momentary removals of ground potential from the conductor'28, relay 3O deenergizes seven times. In so doing, relay 3O completes the circuit for the vertical magnet 36 seven times in series with the slowto-release series relay 34. Relay 34 operates in'series with the vertical magnet 36 upon the first impulse and remains operated through the entire series because of its slowto-release characteristic. Vertical magnet 36, however, follows the impulses and With each operation elevates the wipers 46, 47 and t8 of the selector D one step.

l i hen the switch shaft has been elevated one step, the vertical off-normal springs 87 close and complete the circuit of the rotary interrupter relay 37 from grounded release trunk conductor 3, through make contact and armature 35 oi relay 34:, closed vertical ottnormal springs 37, and thence through the winding of relay 37 to battery. Relay 3? hereupon operates, at its armature 3S prepares the circuit for the rotary magnet to and, at armature 39, locks itself through the self interrupting springs of rotary magnet lO to ground at armature 4% of the switch switching relay l1.

After the seven removals of ground "from the conductor 28, there is an interval when no interrupt-ions take place since ground is maintained on conductor 28 by step relay 144:, Fig. 5, during the time the counting switch CS is being returned to its normal position. Relay 80 0t selector D remains in its operated position during this interval and series relay 34c releases a short time after the last deenergization oi relay 30, at its armature 35 opening the initial energizing circuit of the rotary interrupter relay 37 and connecting grounded release trunk conductor 3 to the winning of the rotary magnet 40, whereupon rotary magnet l0 operates and rotates the switch shaft and wipers one step. This operation or the rotary magnet l0 opens the locking circuit of rotary interrupter relay 37, which relay tnence deenergizes and opens the circuit of the magnet 10. Further stepping of the wipers -16 to as by rotation of the switch shaft is dependent upon the condition or the trunk line with which the wipers are in engagcment as a result of the first rotary step. 7 I the tr .nk with whose contacts the wipers l6 to as are in engagement is busy, ground potential will be upon the test contact there of and will be connected to the winding of the rotary interrupter relay 37 by way oi" test wiper 47, armature l3 and resting contact t switching relay 1- self interrupting springs of rotary magnet 40, vertical ofi-normal springs 37', and tience through the winding of the rotary interrupter relay 37. Thereupon rotary interrupter relay 37 operates and at ar1nat-ure'38 again completes the circuit i'or rotary magnet- 4:0, whereupon the shaft and wipers are rotated another step. It will be noted that, during this time, the circuit of switching relay 11 is complete from grounded release trunk conductor, through the eleventh rotary position contacts 29, .ding of relay 41, through self interrupt springs of rotary magnet 40 and vertical ottnormal springs 37, winding of relay 37 to battery. However, when relay 37 is in its operated position, the winding of relay 4-1 is short-circuited from ground by way of armature l4: and resting contact of relay 4:1, and armature 39 and make contact of relay 37. Ground potential encountered upon busy test contacts by the test wiper 4C7 also short-circuits the relay 41 to prevent its operation when relay 37 releases.

Each time the private wiper 47 engages a grounded test contact the relay 37 and consequently the rotary magnet t0 are operated to rotate the wipers into engagement with the next set of bank contacts. This action will continue until wiper 47 engages an ungrounded test contact associated with an idle trunk or until tl e eleventh rotary step has taken place if all trunks are busy.

Should all of the trunks outgoing from the selector D be busy and the selector advances to eleventh rotary position, cam spring 29 is moved into engagement with its make contact to complete the circuit of busy relay 1a from grounded release trunk conductor 3, cam pring 29 and its make contact, armature 6 and resting contact of relay t, and winding of relay 14- to battery. Relay 14L thereupon operates and its armature 15 looks itself to grounded release trunk conductor 3, at the same time openin the circuit of relay 17, which latter relay falls back and disconnects the sender from selector D. Relay 14, at its armatur 16, connects tne secondary winding of the busy tone transformer T in the substation. battery teed circuit so that the calling subscriber is furnished a busy tone to inform him that the desired connection cannot be established at this time.

The disconnection of the sender from the select: D allows the sender to release without having to transmit the remaining impulses. That disconnection also results in the opening of the circuit of line relay 30 of the selector D, which relay then falls back and opens bile circuit of release relay 31. Relay 31 falls back after an interval and in so doing completes the c'- cuit of the selector release magnet. lhe r lease magnet thereupon operates to restore the selector D in the well-known manner.

For the purpose of this description, it will be assumed that the trunk comprising conductors :32, 53 and 54:, which are connected to contacts 49, 50 and 51, respectively, is the first idle trunk to be eircountercd. l t hen this occurs, relay ll will no longer be shortcircuited and it will operate in series with the rotary interrupter relay 37 over the previously traced circuit. Rel 1y 37, however, because of the relatively h .1 resistance of re ay 41 does not operatively energize in series therewith.

Upon the operation of elay t1, the talking conductors of the selector D are connected through to the trunir conductors 52 and t at armatures 42 and as of relay 41, line relay 30 and release a leS and the circuit or relay 81 are opened at armatures l5 and 44:,

relay-185; Thisrconnection ofrgroundvto conductor. 52".completeszthe circuit for; relay. 14: inithetrnnkarelay groupsRG, Ei'grl', byrway' of bank. contact 49; Wiperi 16, make: contact and armature 42:. of; relay 11 armature 6 and: resting.- contaet of relay 1; of? the? trunk relay:- group .RG; and. thence: through the winding; of; re1aya14; tobattery Relay 1% thereupon :operates,and;at2armature:15, locksitself: to grounded arelease 1 trunk conductor 3 1 and; at armature 16, oonneotsthesecondary windingrof the busy: tone: transformer T in 1 serieswith: the battery feed relay 8, so as to superiinpose busy tone. upon-:the-trunk conductors 11 and Qrthrough thewinding: of the: battery .feedi relay; 8? to lIOlllfYz the calling.

subscriber at substation A that the desired liner is. busy; I

In completing; its locking: circuit atarin'a-- ture 15;relay 1&1 opens'the'circuit of relay 1-7 which relay then deenergizes and"d1sconnects--the Wipersof the senderselector SS from the connector :Ezto free-the sendenwithout its having tozsend the last: series Of'ln'k pulses. The disconnection of the impulse wiper from tliepositive' talking conductor through 1 the selector,- results in the" disconnectioirof' ground fronrther lower Winding. ottheline relay ofwtheconnector-E,wh1cha relay thereupondee-nergizes and opens the circuit of: the release relay: 61, whiclnafter an interval; releases and at its armature 64. and resting conta ct completes the circuit of: the releaser-mag11et=7l= by- Way" of: armature- (39 a-ndresting; eontactot relay 67 and'ver ticaloff-normal springs-70. The releasemag'f net thereupon operateswandrestores tl1e-connector switch I E toitsnormal position; in the usualimannen The removal. of groundvfrom; the. release-trunk conductor-F53by the deen-- ergizationof the release relay; 61- of the con-v nector opens the circuit of. the switching: relay 41 0f theselector Dgwhich relay there-- upon releases and; at armature l l andrresting contact completes the circuit for the selector release magnet. by Way of? armature and resting; contact ofhne relay 30, armature and resting; contactoflrelay 31, and vertical olfnormal springs 33'. The selector. release magnet thereupon operates and 2 restores the selector D to its normal'position-in :the Well known manner.

RelaysS, 10 and: 14 of the trunk relay group are now theonly relays in their operated positions-and-they remainso as-long as the subscriber atthe substation Annaint-ains his receiver oif the receiver hook;

- Assuming, however, that the desired l1ne is idle at: thetimethe connector Wipers- 102' to 104 are placed in engagement with the co1'1ta cts'102 to 104; of the desired line, Wiper 103-does not encounter ground and no circuit iscompleted, therefore; for the relay 72. When relay 85 deenergiz-esafter thetransmission of the four impulses, at: resting contact and armature 87 thereof; the circuit: for the upper Windingof the switch througli ree lay 95' is completed from grounded release trunk-conductor 53 by Way of armatureand resting contact: of relay 72; thence through. theupper Wihding of? the relay 95,

to the: Winding of the cut-off? relay of the lineswitch of thedesirediline'by way-of armaiture 87 and resting contact ofrelay wiper 103, and test c0ntactil03. Thecut-offirelay of the called subscribers lincswitch operates" inlth'e well known manner to disconnect the line relay thereof from the line to prevent the operation of that relay should the called subscriber: desire toinitiate acall before his calling bells have been operated; Thatout of relay also connects ground-to the testieon tact 103' to inarkthe-called line busy to'all other connectors, by placing ground on-theinultipled test contacts-- in all] the banks thereof;

Relay operates when its circuit is so completed and mo ves its armatures- -96'1to 1101*, r IHClHS' VQ,' lnto their operated positions;

thereby; at its armature- 98, locking itself? through: itslower Winding to the comniom lockingconductor 63 r 'Dhennpul'sing circuit in the connector: is now connected byway ofvarmaturei99 and its make contactito the rotary magnetz79 of the ringin frequency selector RF S1 Vhen the icxt' and ilast series of interruptionsoccnr in the circuit: of the line. relay: 55; live: ground: impulsesaretransmitted to the rotary mag;- net 79 of the'ringing: frequency selector,. and, as i a: result-3. the wipers; 79 and' SO" are stepped into engagement; with the. fiftlii sett ofzcontacts: of their banks Relay 8-5 oper-- ates in multiple'; Witlrt'he rotary 111agnet's79.

to. remove ground: from conductor 86 so: thatrelay: 57, Whosecirciut 1s preparede'byr the off-nonnalT'spi-ings 66 ot-the. ringing ire-.-

quencysele'ctor: RF'S- \vhen th at s-witeh makes its first: step; cannot operate until :7 the. in

pulse transmission" has' been completeda. Now, when relay 85 releases at the end of the the two"Win-dingsof: the relay 55" over the:

talking;

conductors

52 and 54." At the same time this-takes placeythe sender connects grounditothe switch Wiper of tlie sender selector: SS consequentlycompleting thecircuit of the relay 1 which operates; as-preii ously explained,- to connectthe trunloconductors 1 and 2 over the talking: conductors relay 89 operates. I

of thesele ctor D to the talking

conductors

52 and 54 of the connector tru'nln This connection of the talking conductors extends the circuit of the .battery-feed-line relay oi. the connector E .over the-calling subscribefls loo) therelr maintainin the rela 55 0 er-,

-- and make contact of switching relay and normally engaged contacts controlled by ar mature 93 of relay 89, to inform the calling subscriber that the bells at the called station are now being rung. 7

Since it has been assumed that switch RFS received five impulses and the wipers 79 and are in. engagement with their fifth bank contacts, 66 cycle ringing current will be applied tothe called subscribers bells over the negative talkingconductor by way of wiper 79 of switch RFS, armature 7 3 and make contact of relay 72, resting contact andarmature of ring cut-oil relay 89, armature 96 and make contact of relay 95, line wiper 102, bank contact 102", over the called subscribers negative line conductor and through the subscribers calling bells to ground. The 66 cycle ringing current is projectedover the just described circuit from superimposed battery of a 66 cycle ringing current generator.

The called subscriber hearing the ringing of his bell, removes the receiver from the switch hook and thereby completes the loop circuit over the line terminating in the contacts 102 and 104, thereby completing the circuit for the upper winding of the ring cutofl relay from the superimposed battery, over the ringing circuit just described with the exception of the bells, through contacts controlled by the called subscribers switch hook,

over the positive line conductor, bank contact 104, positive line wiper 104, make contact and armature of relay 95, armature 93 and resting contact of relay 89, make contact and armature 78 of relay 72, wiper 80 of switch RFS,fifth bank contact and jumper to first bank contact, and upper winding of relay 89 to grounded common locking conductor 63'. Relay 89 operates in this circuit, at its armature 91 looks itself up to common locking conductor 63 through its lower winding, and at armatures 90 and 90 opens the ringing circuit and extends the called subscribers loop to the windings of the back bridge relay 67. At armature 92, relay 89 prepares a substitute locking circuit for itself which will be independent of the armature 63 of release relay 61 when the back bridge relay 67 operates, which it does shortly after the ring cut-off to the connector IE, it willbe noted that as before explained, the battery feed source-P through the windings of relay 8 is disconnected from the trunk conductors 1 and 2 to thereby substitute the battery feed source P1 for the source P. As before explained this disconnection of relay 8 results in the freeing of the sender for use in the extension of other 1 calls. v

The connection as now describedin the trunk relay group, in the selector'D, and in the connector E, is maintained as long as the two stations remain in talking connection with each other, and no change takes place until one or both of the subscribers replace their reccivers on the receiver hooks.

Release "of connection Should'the calling subscriber at substation A'be the first to replace his receiver upon the receiverhook, the-loop circuit over conductors 1 and 2 is opened and consequently results in the release of line relay 55 of the connector E. Relay 55,-in releasing, at its armature 56 opens the circuit of release relay 61, which relay after an interval deenergizes and at its armature 62 removes ground from the release trunk conductor 53, thereby opening the holding circuit for switching relay 11 of the selector D. At its armature 63, relay 61 removes one ground connection from holding conductor 63 ground being maintained thereonthrough armature 68 and make contact of relay 67 and grounded armature 92 and make contact of the ring cut-off relay 89. At its armature 64, relay 61 prepares the circuit for the release magnet 71 of the connector E, the circuit for release of the magnet being maintained open at armature 69 of back bridge relay 67. At armature 65, relay 61 completes the circuit for release magnet 80 of the ringing frequency selecting switch RFS from grounded armature 60 and make contact of relay 57. V

The completion of the circuit for the release magnet 80 of the switch RFS results in the return of wipers 79 and 80 thereof to their normal position, in which position the switch opens its off-normal contacts 66, thereby opening the series circuit of relays 57 and'72. Relays 57 and "2 thereupon deenergize, and relay 57 at armature 60 opens the circuit of the release magnet 80 of the switch RFS. Further release of the connector E is dependent upon the replacement of the receiver upon the receiver hook at the called station. r

In the selector D, relay 41 falls back when ground is removed from the release trunk conductor 53, and, in so doing, at its armature ll and resting contact completes the circuit or the selector release magnet by way of arni-ature' and resting contact of relay 30, armature and resting contact of relay 31, and through vertical off-normal springs The release magnet of the selector 1) operates, and, in the well. known manner, restores the switch-shaft and wipers to their normal position, therebye openingt-he oil-normal springs 33 to, open the release magnet circuit.

The removalsot ground from the release trunk conductor 53 of the connector E results in the removal oi": ground from the release trunk conductor 3 and release trunk conductor 3. The locking circuit of relays 4 and 14 are thereby opened and these relays release, restoring the trunk relay group RG to its normal position, or that in which the relays thereof are shown in Fig. 1.

The replacement of the called subscribers receiver upon the receiver hook results in the openingwof the circuit of the back bridge relay 67, which relay thereupon deenergizcs and, in so doing, atarmature 6S, removes ground from; the common locking conductor (53!, and at its armature 59 and resting contact,- completes the circuit of the connector release magnet 71. Relays S9 and 95, which are locked up through their lower windings to the common conductor 63, deenergize as a result ofthe removal of ground from that conductor.

Release magnet 71 operates, when its circuit is completed at armature 69 and resting contact of relay 6, and in the well known manner restores the connector to its normal position. Theequipment is now in readiness to be taken into use for-the establishment of another connection.

Ringing source and application sender,- comprises five or less impulses, one

ofthe five sources of ringing current will be applied to the called subsoribers bells by way of wiper 79 and then over the negative talkin conductor. If the" rin ing frequency digit comprises more than five impulses, the rimging current will be applied over the positive talking conductor to'the called subscribers' station by way of wiper 80. This is the well kn-own manner of code ringing in the case of a ten-party linetelephone system.

Metering When the calling subscribers lineswitch C finds an idle trunk upon the subscriber at substation A initiating a call, as has been explained, the current for the calling subscribers circuit is supplied from the battery feed source P. Since, as explained, this source is one which at predetermined intervals reverses the polarity of this current in the calling subscribers circuit, the operation of the elapsed time meter M is commenced substantially at the time when the calling subscriber removes his receiver from the receiver hook since the hunting time of the lineswitch C is practically negligible. When the desired line is found to be idle by the connector E, the battery teed source P1 is substituted for the source P, and the operation of the elapsed time meter M continues until the calling subscriber replaces his receiver upon the receiver hook.

It will be remembered, that, in the case where the selector D could find no idle trunk leading to a succeeding switch and in the case where the connector E found the desired line to be busy, the relays 8, and 1% of the relay group HG were held operated while the selector D and the connector E were released. That condition resulted in the application of busy tone to the calling subscribers line by the superimposing of busy tone current upon the current from the source P. Inasmuch as the current from the source P is applied to the subscribers circuit as long as the subscribers receiver remains oii the hook, the. operation of the elapsed time meter M takes place until the subscribers circuit is opened by the replacement of the receiver on the receiver hook. In this manner the calling subscriber is charged for substantially all of the time his telephone is in use in the establishment of a connection.

lVhen the subscriber at substation A is the recipient of a call, the subscribers meter is not operated since no current reversals take place over the conductors 1 and 2 inasmuch as the talking current is supplied through the back brid e relay of the connector in use, which relay has its windings connected direct to'a constant polarity source as may be seen in the case of the back bridge relay 67 of the connector E.

The invention having been thus described,

- what is considered new and what is desired to have protected by Letters Patent will be pointed out more specifically in the claims which follow.

WVhat is claimed is:

1. In a telephone system, a calling line terminating in an exchange, a meter for said line, a trunk, means responsive to the initiation of a call over said calling line for connecting said line and trunk together, and

means responsive to said connection for periodically operating said meter as long as said connection is maintained.

2. In a telephone system, a calling line, a meter therefor, a trunk, a source of periodically pole-changing current, and means responsive to the initiation of a call over said line for connecting said line to said trunk and connecting said current source to said line, said source connected to said line to sup ply talking current to said line and periodically operate said meter.

3. In a telephone system, a calling line, a meter therefor, a trunk terminating in a se lector, a source of periodically pole-changing current associated with said trunk, a plurality of connectors, means responsive to the ini tiation of a call over said line for connecting said line to said trunk and connecting said current surce to said line for periodically operating said meter, means for operating said selector to cause it to automatically hunt for an idle one of said connectors, and means operated by said selector when it finds all of said connectors busy for supplying a busy tone to said line While maintaining the periodic operation of said meter.

4. In a semi-automatic telephone system, a calling line, a meter therefor, a called line, a trunk terminating in a selector, a source of periodically pole-changing current associ ated with said trunk, means responsive to the initiation of a call over said calling line for connecting said line to said trunk and connecting said current source to said calling line for periodically operating said meter, a connector, an operators position, means associated with said trunk and responsive to the connection of said calling line with said trunk for connecting said trunk to said operators position, said current source supplying talking current to said calling line, means associated with said position for operating said selector to extend said calling line to said connector and for thereafter operating said connector to extend said calling line to said called line, a second source of periodically polechanging current associated with said connector, and means responsive to the extension of said calling line to said called line.

for transferring the periodic operation of said meter from the first mentioned source of pole-changing current to said second 5. In a tele )hone s 'stem a callins line a meter therefor, a called line, a trunk terto said trunk for periodically operating said meter until said calling line is connected with said called line, means responsive to the connection of said calling line with said called line for transferring the operation of said meter to said connector, and means in said connector for thereafter periodically operating said meter.

6. In a telephone system, a calling line, a

meter therefor, a trunk, non-numerical means for connecting said line with said trunk, a train of switches accessible over said trunk, means for operating said switches for extending a call from said line, and means responsive to the connection of said line with said trunk for periodically operating said meter as long as said connection is maintained regardless of the success of said train of switches in extending the call.

7. In a telephone system, a calling line, a meter therefor, a called line, a trunk, means responsive to the intiation of a call over said calling line for connecting said calling line with said trunk, means for connecting said trunk with said called line provided said called line is idle, and means for periodically operating said meter responsive to the connection of said calling line with said trunk and for continuing that periodic operation as long as said calling line is connected with said trunk regardless of whether or not said trunk is connected with said called line.

8. In a telephone system, a calling line, a

meter therefor, a two section trunk, a first source of periodically pole-changing current normally connected to the first section, a second source of periodically pole-changing current, means for connecting said line with said first section to commence the periodic operation of said meter by said first current source, means for connecting said second current source to the second section of said trunk, and means for disconnecting said first section from said first source and connecting said first section to said second section to transfer the periodic operation of said meter to said second source.

9. In a telephone system, a calling line, a meter therefor, a called line, a two portion trunk terminating in a selector, a first source of periodically pole-changing current normally connected with one portion of said trunk, means responsive to the initiation of a call over said calling line for connecting said calling line with said one trunk portion to thereby connect said first currentsource to said line for periodically operating said meter, a connector, a second source of pole-changing current associated with said connector, means for operating said selector to extend the other portion of said trunk to said connector and for thereafter operating said connector to extend said other trunk portion to said called line, means in said connector operating automatically if said called line is idle when said other trunk portion is extended thereto to connect said other trunk portion to said called line and to connect said second current source to said other trunk portion, and means for thereafter disconnecting said one trunk port-ion from said first source and connecting said one portion to said other portion to transfer the periodic operation of said meter to said second source.

10. In a telephone system, a callin line, a meter therefor, a called line, a two portion trunk terminating in a selector, a first source of periodically pole-changing current normally connected with one portion of said trunk, means responsive to the intiation of a call over said calling line for connecting said calling line with said one trunk portion to thereby connect said first current source to said line for periodically operating said meter, a connector, a second source of polechanging current associated with said connect-or, means for operating said selector to extend the other portion of said trunk to said connector and for thereafter operating said connector to extend said other trunk porti on to said called line, means in said connector operating automatically if said called line is idle when said other trunk portion is ertended thereto to connect said other trunk portion to said called line and to connect said second current source to said other trunk por tion, means for thereafter disconnecting said one trunk portion from said first source and connecting said one portion to said other portion to transfer the periodic operation of said meter to said second source, means in said connector for preventing the connection of said other line and the connection of said second source to said other portion if said called line is busy, and means responsive to the operation of said preventing means for supplying said calling line with a busy tone while maintaining the periodic operation of said meter by said first source and for causing the release of said selector and connector.

11. In a telephone system, a calling line, a meter therefor, a called line, a trunk having a first section and a second section, a first source of pole-changing current normally connected to said first section, a second source of pole-changing current associated with said second section, means for connecting said first trunk section with said calling line to connect said first current source to said calling line to periodically operate said meter, means for connecting said second section to said called line and for connecting said second current source to said second section, and means for disconnecting said first section from said first source and for con trunk portion to said called 'necting the two sections together to transfer the periodic operationofssaid meter to said second source.

12. In a telephonesystem, acalling line,

a meteritherefor, a first'source ofperiodically pole-changing current, .a second source of periodically pole-changing current, means responsive tothe initiation ofacall over said line for connecting said first source to said line to periodically operate said meter, means for extending the initiated call, and means for thereafter disconnecting said line from said first source and connecting it to said second source to transfer the periodic operation of said meter to said second source.

13. In atelephone system, a calling line, a meter therefor, a first source of periodically pole changing current, a second source of periodically pole changing current, means responsive to the initiation of a call over said line for connecting said first source to said line to periodically operate said meter, means for extending the initiated call provided no busy condition is encountered, means operable where the initiated call is extended for' disconnecting said line from said first source and connecting said line to said second source to transfer the periodic operation of said meter to said second source, and means for preventing the operation of said last means if a busy condition is encountered, thereby maintaining the periodic operation of said meter by said first source.

14. In a telephone system, a calling subscribers station, a line therefor, a meter associated with said line, a trunk having means for periodically operating a meter, means responsive to the removal of the receiver from the receiver hook at said station for connecting said line to said trunk, said means thereupon periodically operating said meter.

15. In a telephone system, a calling line, a meter therefor, a trunk having a source of periodically pole-changing current associated therewith, and an automatic switch responsive to the removal of the receiver from the receiver'hook at the substation of said line for connecting said line to said trunk and said source of current, said pole-changing current thereupon periodically operating said meter.

16. In a telephone system, a calling line provided with a meter, a called line, a train of switches, a trunk incoming to the first switch of said train, means responsive to the initiation of a call over said calling line for connecting said calling line to said trunk, means associated with said trunk and rendered eifective by the connection of the calling line thereto for periodically operating said meter, means for operating the switches of said train successively to extend the call to said called line, and means responsive to the encountering of a busy condition by anyone CAI of said switches While attempting to extend the call for supplying abusy tone to said calling line Without affecting the periodic operation of said meter.

In Witness whereof, I hereunto subscribe my name this 5th day of April, A. D. 1930.

NORMAN H. SAUNDERS.