US2252629A - Supervisory signal system - Google Patents

Description

Aug. l2, 1941. F. H. HANLEY ETAL SUPERVISORY SIGNAL SYSTEM Filed April 19, 1940 Patented Aug. 12, 1941 UNITED STATA-ES PATENT r Vsurenviso'nv SIGNAL SYSTEM M Frank ,Harold lllanlefy,` Butler, and `rank-J. [,Car-

ter, 'Millburn, N. J., `Orville HowardjDavidsmeyer,` Downers l(grrove, 'Il1.,` and Otha M Lamberson, FlushinggN. Y., assignors of Jtwothirdsto AmericanTelephone and`f1elf'egraph` j Company, a corporation of New York, andone-r" w i third to Bell Telephone Laboratories, Incorpof l rated, a corporation of New York Appucanm AprilV i9, 1940, serialV Noj 330,594 V12v claims. reina-v5) This invention relates to signaling systems",l and moreHparticularly-to telegraph systems, including sc -ca'lled KSP circuits.` With greater par# ticularity," the` invention relates to"syfsteins"in which KSF circutsfare interconnected"I atga switching 'point for throughfoperation ,by means of. a twof-conductor cord circuit repeater, with the requirement, for efficient operation, of certain supervisory sgnaling'features.

KSP circuits, the letters indicating inter-cnice communication circuits -formerly 'jknown as communication `spare patch-ing i circuits.` @In some Yin'stancesfit is found ythat between certain onices the number of thev attendants communi` cations is'not large enough'tI justify` the provision of direct KSPcircuits. According1y, it becomesnecessarii o r` desirablefto provide at cer--A tain pointslswitching arrangements by the use of iwhichlconne'ctions can be f built up to handle the attendants calls between` 't lfose`oices.

The desired 'switching is satisfactorily taken care' of'f throughthe 'instrumentality of a twoconductor." cord circuit repeater provided at the switching ollice:` `The use foi such a repeater, however, involves'problems of` supervisory'signalling between attendants. More particularly,

there' must be provision for busy and disconneetr signals without unduef interference with the4 communicationover the-KSPcircuitsf To meet satisfactorily therequirement just L stated withf a single" indicator rperrepeater appearance isv the principalobjec't'- cf the present invention'. Another `object ofjtheinventionisto provide for4 supervisory 'signaling in association with a cord lcircuit repeater, which signaling willb'e Vsat; isfactoryfin'fcases offopereltion at theswitc'hing oflice one; multiple basisf Aj further' object of the invention is to provide for the supervisorysignaling indicated hereinbe# reasonablylecono'mical.

\ fore byv means of apparatus which is simpley and The inventionmay be generallydescri the `co`mbination`- o'ffa cord vcircuit rep 'v supervisory signal, indicating meanstfa mated` means for causrlg` the; signer means to junctionV ior the indication bus'yf for; time?) @fumo and t of afdiscon" tsign al ."f f-.Oiheri'obieg and, advaltaeszof .the inver; will beinade cle inthe folioifiijngdetailed e-,

s cription off 'onjef1 desirable,embodimenttlieren reference theaccomwhich is toi-be ad ranyirigdrawina l It is deemed desirableto describe the invention in a form adapted togoperaticn on"a;`multiple basis.. The I Inodiiications"v .ci this form ivvlfiiclfi leave the' epparatusledffirciliie .et fieri operation on a non-niultiple basis herwill'be obvious or will be pointed out. 1n the drawing?-` ff l j 5 g Fig'ure 1 shows cliagrarnri'fiati-callyV 4and in'part schematically,thearrangement offthe cord circuit` repeater and the jdir'ectly'associated fappa ratus andcircuits forfpovidipg thefdefsiredy uipervisory signalsat'the repeater posit' Fig.v 2 shows diagrammatically suitable1 appa# `ratus directlyl associated with aV Ksljfcircuit tiple,` which apparatus functions in coperatiri with the apparatusshown in Fig.v 1;I and; v Fig. 3` shows' diag'rar'nniatically-iandinrpart schematicjauy suitableapparatus 'at inventing? ofce' for transmitting the\ disconnectvA sigan-al to the repeater point. f' "Withreference' te the detailsotV the drawing and iirstl with particular ref erenceto" Fi "l", the apparatusv at the Iswitching oice "includes" a single line telegraph repeater and rtelegraph lopf--terminalsf'li and Ta The repeater is terminated on en -'inward cord'and `anY outward cordl-"'Two appearances oi the irepeater areshown, repref' sentativ'e of anysuitable number of'niultiple *ap-- pearances, at positions t and2. The 'inward cord' terminations are on plugs P1 and P1, re'-V speetiveiyf; similany the 'outward ecru terminates onplugs P2 andPz at tl'ietwoA positions respectively-. 'The 'signal iridicator'fat positi'oiir l takes theform of a'lamp L While-l-ainpl is provided at the' second positionf' Directlyas'sociatedwith each repeater positionfonthe board'is'afboard relayiR' r'R "`with a plurality of armatures and contat's. 'It will be understoodthat if the' operation is on a non-"multiple basis,` one setof` plugs', lamp and board relay'-foriexample, -P1I,"P2`,`f L and E -suilices and thevassociat'edconnecting circuits; are accordingly simplified;r '1'Il1 remainingl apparatus 'of Fig.: f1 includes *a leak relay R,

a transfer relay R2, a line relay Ra having a winding in circuit with the inward cord, an alternating current relay R4, a delay relay R5 and a signal relay Rs, all with suitable connections and arrangements for voltage supply, as will be more clearly understood from the following detailed description of the operation of the system as particularly affecting the apparatus of Fig. l.

It is assumed that the repeater and the KSP circuits are operated on a multiple basis.I yIf the repeater is in use by an attendant at any position, the attendants at all other positions are advised of this fact by a repeater busy signal, as will be discussed more fully hereinafter this indication is given by the lighting of lamp L or L associated with the particular repeater appearance. If it is noted that the repeater is idle, the attendant who has to make afswitched KSP call makes with the tip of the outward cord a busy test of the KSP multiple. The apparatus provided for this test will be fully disclosed hereinafter in connection with the discussion of Fig. 2 of the ,drawingsV ,It suii'ices to state at this point that if .the tested KSP circuit is busy, the lamp will light. Ifthe test indicates that the particular KSP circuit is idle, the plug of the outward cord is inserted `into the jack of the KSP multiple.` By circuit arrangements which will be more fully disclosed in connection with Fig. 2, battery is applied to the tip of the outward cord and the circuit is completed through contact 4 of relay R2 and the winding of the leak relay R1 to ground, this circuit constituting a leak circuit on the tip of the cord. Relay R1 operates and by the closing .of its upper armature and contact completes a circuit lfrom lbattery B1 through resistances 6 and 6 and contacts vI and I of relays R and D', respectively, to the lamps L and L', it being understood `that lamps corresponding to any additional multiple appearances ofA the repeater will have their lament circuits similarly completed. The lightingy of the lamps thus produced gives a busy-indication at all appearances of the repeater; The operation of relay R1 also closesthe lower armature and contact to apply ground'over that armature to the lower or secondary windings of relays R and R and any other board relays which may be added to correspond to additionalV multiple appearances. When the inward cord of the repeater is inserted by the attendant at one position into the jack of the calling KSP circuit, the upper or primary winding of the associated board relaywhich for the purpose of illustration will be taken to be relay R corresponding to position I-is energized, the source of the energy being more fully discussed hereinafterl in connection with Fig. 2. Relay R will now operate and by the action of the armature shown below the electromagnet in the drawing opens contact 'I, thus Vextinguishing lampL Yat position I where the' connection is being made. By the upper contact of the armature now made, this lamp L is vconnected to the armature of the signal relay Re and is thus placed in position to receivea disconnect signal from the calling oiilce. When relay R operates, the closing of contact 8 completes a locking circuit for the relay from battery B through-contact 8,

the lower winding of the relay and the lower contact and armature of relay R1 to ground over the last mentioned armature.

The closing of contact 9 upon the operation yoi relay R connects battery B to ground through the winding of the .transfer relay R2. This transfer relay operates to open contact 4 and close contact I U, thus transferring the winding of the leak relay R1 from the tip of the outward cord to the sleeve of that cord. This transfer operation places the leak relay in a position such that the relay does not interfere with the transmission path and yet is maintained in operated condition.

It will be noted that with the connection completed through the repeater at the switching ofce, lthe upper or line winding of the line relay R3 Lis included in the inward cord circuit. As

4stated hereinbefore one of the objects of the invention is to lindicate by the signal indicator, l5'

such as lamp L, the reception of a disconnect signal from the connected calling oflice. It is, of course, necessary that there be satisfactory discrimination between the disconnect signal and any other signals transmitted over the built-up circuit. As will be more fully considered hereinafter in connection with Fig. 3 of the drawing, the distinctive signal transmitted for disconnect purposes may take the form of a 20- cycle ringing current. vIt will be noted that relay R3 includes a biasing winding and has certain circuits `associated with the marking and spacing contacts of its armature. When the distinctive 20-cycle ringing current comes in from the calling oice, the operation of relay R3 causes the alternate charging of condensers C1 and Cz through the lower or secondary winding of the alternating current relay R4 and the discharging of these condensers through the upper or primary winding of relay R4. This relay is designed for slow release. Condensers C1 and C2 form a part of the resonant circuit including the retard -coil II and this resonant circuit is tuned very closelyto 20 cycles per second; accordingly, the condensers can be fully charged and discharged only at a rate which corresponds to or is very 'close to the resonant frequency. Resistances I2 and I3 and condensers I4 and I5 are provided for the purpose of reducing sparking at the contacts of the line relay R3. The alternating current relay R4 operates on the `charge and discharge of condensers C1 and C2 at the predetermined frequency, the marginal feature of the relay preventing its operation when the interrupting frequency of the signaling current differs from the predetermined frequency.

The delay relay R5, which is provided for the purpose of guarding against false operation of the signal receiving circuit on Morse signals, for example, is made slow-releasing and is normally in operated position, the relay circuit being shown as extending from ground at I6 through battery B2 and the relay winding to ground at I1. In this position of the relay, its contacts are open. When the alternating current relay R4 operates, ground at I8 is connected through the armature of relay R4 to complete a circuit for the battery B2, and thus the winding of relay R5 is short-circuited and that relay releases after Va suitable interval. It will be noted that upon the release of relay R5, it is locked in the released position, the locking circuit extending from ground at I6 through battery B2, the upper contact of relay R5 and the lower-,contact of the leak relayr R1 to ground. 'Ihe closing of the lower contact of relay R5 upon its release completes a circuit through battery B3, that contact and the winding of the signal relay Rs to any suitable device for interrupting the circuit thus completed at a frequency of 60 interruptions per minute, the interrupting device being one well understood in the art and indicated on the draw-'-` ing as 60 I. P. M. The signal'relay Rs'follows the 60 interruptions per minute and inter` mittently connects battery B4 through itsupper armature and the closed contact 22 of board relay R to lamp L at the position where 'the through connection has been made. \The esultantv flashing of this lamp indicates ythe reception of the disconnect signal from the calling KSP ollice. It will be noted that theaarmature of relay R', which isunoperated, rests on its lower contact 1', leaving contact 22 open,y and consequently there is no` disconnect signal circuit completed through the. lamp L. .Thus pron vision is made for the appearance of the` nashing disconnect signal at the 'repeater position where the through disconnection has been ,made and at no other appearance of the repeater.`

After the reception of the flashing disconnect signal the attendant `removes the inward and.

outward cords simultaneously and the leak relay R1 is released. The release of this` relay removes the ground on the locking circuit of the board relay R (or any other board relaywhich may have been operated) and this board relay is restored to,Y normal position, causing the release of the transfer relay R2. `As a result of the re-` leaseof relays R1, R` andRz, the repeater `busy lampsat all appearances'are extinguished and the locking circuit iorfthe` delay relay R5 is opened, relay R5 returning to its-,normal operated position. Consequently, the circuit through the winding of the signal relay Rc is opened and the disconnect signal circuitithusbroken.` 1 v- It will be noted `on Fig.` 1 ofthe drawing that the signal `relay Re may be provided `with a'second (lower) armature and contact for the purpose of controlling an auxiliary signal circuit if such is desired. y -f When the repeater is provided at olices having a KSP circuit multiple, there mustl be cirT cuit arrangements at the repeater` position whereby it may bel ascertained by .the attendant whether or not a desired KSP circuit is busy. A satisfactoryarrangement is one-in accordance with` which `eachKSP circuit is equipped with a relay and other apparatus ior placing the sleeve of each multiple jack at Zero potential if the circuit is idle andat some potentialsuch as l65 voltsiiythe circuit is,busy.v` I t is desirable that thisuprovision be made `without interference with the transmissionpaths of they circuit, which also utilize Vthesleeves of the jacks The arrangement for producing the non-voltage and voltage condition ofthe jack sleeves, used in conjunction with'the `tiptest circuit on the outward cord of the repeaten-.is shown in adequate detail in Fig. 2-of the drawing.` Thisvdisclosure includes an Vindication ofthe `KSP multiple with an initial appearance fandfa final appearance, relays Re Vand Rv` and suitablelresistances and sources of potential, as will now be `described in further detail. y

With no' connection `festalclishedto kthe KSP circuit multiple,a zcircuit is completed from ground through battery B5, the right-hand or primary winding ot relay Rs and the `auxiliary contacts [Band llll `of the KSP vmultiple jacks to ground.` In this. condition-the shunt across resistanceswZl. between Ytilearrriature of relayRs n and thel contact` of that relay isopenV and-,the sleeves of all "of the jacks of the KSB/circuit multiple are inthe electrical center of the `KSP loop circuit. This condition has the result that there is no potential touground on the sleevesof the -jacks associated with the KSP multiple. .If an attendant makes a tip busy test with the outward cord ofthe repeater by touching the tip to the sleeve of the KSP multiple, no voltage is applied to the test circuit and the leak relay R1 (Fig. l) does not operate `to light the signal lamps. lfynow, an incoming KSP signal is received:thenperating circuit of relay R7, which is completed through contactsZU and 20 of the KSP` multiple circuit, `if opened, relay R1 re* leases andbattery Bsris connected through the relay"armature` in a circuit including the lefthand or secondary winding of relay Rs, this latter circuit being completed.v over the auxiliary contacts I9 and I9 to ground. f VThe current thus caused to flow through thesecondary winding of relay R8 is `equal and opposite in direction to the current of the primary winding and, as alresult, relay Rs is released to close its contact. The closing of the "contact of this 'relay applies a shunt to resistances 2| and, consequently, the sleeve of` the KSP multiple is placed otherwise than at the electrical center of the circuit; in the specic disclosure of the drawing there will be applied to the sleeve a potential amounting to about volts to ground. If, under this condition, the tip `oflthe outward cord of the repeater is touched to the sleeve of the called KSP circuit, this potential of 65 volts causes a current to now through the winding of the leak relay 'Ri (Fig: l) :to ground,` theresult being the operation of the leak` relay and they connection of `battery B1 to the lamps L and L'. When a plug is inserted 4in the KS-P multiple, the `auxiliary contactnl!! or I9 is opened and relay Rs is released. i f i l l If an `attendant at one repeater' position has established a connection `by .plugging in at one appearance of a certain KSP circuit in the KS-P circuit multiple,` and :another attendant desires to vbuild up `a connection-over that circuit, the tip ltest'will` produce abusy indication since the established connection will have resulted in the opening of either Contact I9 or contact |9,\the removal of the ground from the right-hand winding of relay Ra andthe closing of the shunt aroundl resistances `2 I .Y

It will be `observed ythat the 13D-volt circuit shown in Fig. 2` `notonly provides the holding current for relay R7 but also furnishes the potential for the operation of the leakrelay R1 of Fig. 1 under'appropriate conditions.

As `,has beeny indicated hereinbefore, in order that there may be Aadequate discrimination at the switching oilice'between` a disconnect signal and Morse signals, for example, a distinctive signalmust be sent from the calling oilice connected ina built-up KSP circuit. The diagram of Fig. 3 indicatesra suitablel arrangementwhich may be providedior this purpose at an-office which will -be regarded "as a -calling office. When *this ofce .has completed the communication over,` the built-up KSP circuit, the nonlocking ,key K associated with the telegraph test set is operated for ,approximately two seconds. This` operation applies 1Z0-cycle ringing current-through the Asounderlofthe telegraph set to the tip of plug P, which* terminates the cord, and on Yover .the telegraph `circuit tothe KSP repeater point, The transmission of the 20cycle ringing current through the sounder of the telegraph set is necessary inorder that theattendant at the calling oflicemay'be assured that the disconnect signal-has been transmitted. `As has been described insomedetail in connection with Fig. 1, the'receptionr at the KSP repeater oiiice of this distinctive disconnect signal is indicated by the flashing of the signal lamp at the repeater position through which the connection is made.

While the invention has been disclosed speciiically as applied to KSP circuits used in certain telegraph systems, it will be understood that it may be applied to other communication systems. Likewise, it will be understood that many changes from the specific arrangement shown may be made vwithin the scope of the appended claims.

What is claimed is:

1. In a signaling system including a plurality of oflices and a plurality of direct point-to-point circuits interconnecting certain of said oiiices, a cord cir-cuit repeater at one oflice for connecting two" of said direct circuits for through operation between two other offices, `a signal indicator associated with said repeater, and means associated with said'indicator for indicating lthereby whether a certain direct circuit is in use and the reception of a distinctive signal from the calling office.

2. In a signaling system including a plurality of oiiices `and a plurality of direct point-to-point circuits interconnecting certain of said oiiices, a cord circuit repeater at one office for connecting two of said direct circuits for through operation between two other oices, said repeater and said direct circuits being adapted for operation on a multiple basis, said repeater having at each of its appearances asignal indi-cator, and means associated with said indicator for indicating thereby whether the repeater is in use at another position, whether a certain direct circuit is in use, andthe reception of a disconnect signal from the connected calling cnice.

3;' In Va signaling system including a plurality of oilices and a plurality of direct point-to-point circuits interconnecting certain of said oiiices, a two-conductor cord circuit repeater at one oiiice for connecting two of said direct circuits for through operation between two other oflices, a signal indicator associated with said repeater, and circuit means associated with said indicator for indicating thereby the idle or busy condition of a certain direct circuit and the reception of a distinctive signal from the connected calling oiiice.

4. In a signaling system, including a plurality of oflices and a plurality of direct point-to-point circuits interconnecting certain of said oiiices, a two-conductor cord circuit repeater at one oflice for connecting two of said direct circuitsfor f through operation between two other offices, said repeater and said direct circuits being arranged for operation on a multiple basis, a signal indicator associated with said repeater at each of its appearances, and circuit means associated with said indicator and indicating thereby the use of the repeater at another position, the idle or busy condition of a certain direct circuit and the reception of a distinctive disconnect signal from the connectedcalling oflice.

5; In a signaling system including a plurality of offices and a plurality of direct point-to-point .circuits interconnecting certain of said oices, a cord circuit repeater at one oice for connecting two of said directl circuits for through operation between two other ofiices, said repeater having an inward cord, an outward cord and a single signal indicator, means associated with said indicator for indicating thereby whether a certain one of said direct circuits is in use, and means associated with said indicator and operable when a connection has been established for indicating by said indicator the reception of a disconnect signal from the connected calling oflice, said last stated means being responsive only to current of certain distinctive characteristics..

6. In a signaling system including a plurality of oliices and a plurality of' direct point-to-point circuits interconnecting certain of said offices, a cord circuit repeater at one oiice for connecting two of said direct circuits for through operation between two other oices, said repeater and said direct circuits being arranged for operation on a multiple basis, saidrepeater having an'inward cord and an outward cord each adapted for switching operations at each appearance of the repeater, a signal indicator associated with each multiple appearance of the repeater, means associated with said indicator for indicating thereby whether the repeater is in use at another position, means associated with said indicator for indicating thereby whether a certain one of said direct circuits is in use, and means associated with said indicator and operable when a connection has been established at the corresponding position of the repeater for indicating by said indicator the reception of a disconnect signal from the connected calling oiiice, said last stated means being responsive only to current of certain distinctive characteristics.

7. In a signaling system including a plurality of oi'ces and a plurality of direct point-to-point circuits interconnecting certain of said oiiices, a cord circuit repeater at one oflice for connecting two of said direct circuits for through operation between two other ol'lices, a signal indicator associated with said repeater, means for sending to said repeater from a distant calling office connected therethrough a distinctive supervisory signal, means associated with said repeater and responsive only to the reception of said supervisory signal for producing a distinctive operation of said indicator, and means for indicating by said indicator the idle or busy condition of a certain one of said direct circuits.

8. In a signaling system including a plurality of offices and a plurality of direct point-topoint circuits interconnecting certain of said oices, a cord circuit repeater at one office for connecting two of said direct circuits for through operation between two other offices, said repeater and said direct circuits being arranged for operation on a multiple basis, a signal lamp associated with each appearance of said repeater, means for sending to said repeater from a distant calling oice connected therethrough current of distinctive characteristics, means including a chain of relays associated with said repeater for causing said lamp to flash in response to the reception of said distinctive current, and means for causing said lamp to indicate the use of the repeater at another position and the idle or busy condition of a certain one of said direct circuits.

9. In a signaling system including a plurality of oices and a plurality of direct point-to-point circuits interconnecting certain of said olces, a cord circuit repeater at one ofce for connecting two of said direct circuits for through operation between two other offices, said repeater including an inward cord, an outward cord and a signal lamp, a direct circuit multiple associated with said direct circuits and said repeater, means responsive to the touching of the tip of said outward cord to a jack sleeve of the direct circuit multiple associated with a busy direct circuit for lighting said lamp, and means operable when a connection has been established through said repeater for` ashing said lamp in response to the reception of a disconnect signal from the connected calling oflice, said last stated means being responsive only to current of certain distinctive characteristics.

10. In a signaling system including a plurality of oices and a plurality of direct point-to-point circuits interconnecting certain of said oi`ces, a cord circuit repeater at one -oilice for connecting two of said direct circuits for through operation between two other offices, said repeater including an inward cord and an outward cord and being adapted for operation on a multiple basis, a signal lamp associated with each appearance of the repeater, a direct circuit multiple associated with said direct circuits and said repeater, means for lighting said lamp when the repeater is in use at another position, means responsive to the touching of the tip of said outward cord to a jack sleeve of the direct circuit multiple associated with a busy direct circuit for lighting said lamp, and means operable when a connection has been established through said repeater at one of its positions for ashing the lamp at that position in response to the reception of a disconnect signal from the connected calling oilice, said last stated means being responsive only to current of certain distinctive characteristics.

11. In a signaling system, including a plurality of offices and a plurality of direct pointto-point circuits interconnecting certain of said offices, a cord circuit repeater at one office for connecting two of said direct circuits for through operation between two other offices, said repeater including an inward cord and an outward cord, a signal lamp associated with the repeater, a direct circuit multiple at said office including a plurality of jacks, means associated with said multiple for impressing a voltage on the sleeves of the jacks corresponding to a certain direct circuit when said circuit is in use and for removing the voltage when the circuit is idle, and circuit and switching arrangements associated with said repeater and said lamp whereby the lamp will give a plurality of indications, said arrangements including means responsive to the touching of the tip of said outward cord to a multiple jack sleeve when a voltage is impressed thereon for lighting said signal lamp, means responsive to the connection of the outward cord with said direct circuit multiple for lighting the lamp, means responsive to the completion of a connection through the repeater for extinguishing the lamp and preparing the same for the reception of a disconnect signal from the connected calling ofce and means responsive only to current of certain distinctive characteristics transmitted from said calling ofiice for causing the dashing of said lamp as a disconnect signal.

12.111 a signaling system including a plurality of oiiices and a plurality of direct pointto-point circuits intercononecting certain of said oices, a cord circuit repeater at one ofli'ce for connecting two of said direct circuits for through operation between two other oi'lices, said repeater including an inward cord and an outwardl cord and being designed for operation on a multiple basis, a signal lamp associated with'each appearance of the repeater, a direct circuit multiple at said office including a plurality of jacks, means associated with said multiple for impressing a voltage on the sleeves of the jacks correponding to a certain direct circuit when said circuit is in use and for removing the voltage when the circuit is idle, and circuit and switching arrangements -associated with said repeater and said lamps whereby the lamps will each give a plurality of indications, said arrangements including means responsive to the touching of a tip of the outward cord to a multiple jack sleeve when a voltage is impressed thereon for lighting said signal lamps, means responsive to the connection of the outward cord with said direct circuit multiple for lighting the lamps at all repeater positions, means responsive to the completion of a connection through the repeater at one position for extinguishing the lamp at that position and preparing the same for the reception of a disconnect signal from the connected calling oflice, and means responsive only to current of certain distinctive characteristics transmitted from said calling oice for causing the ashing of said lamp as a disconnect signal.

FRANK HAROLD HANLEY.

FRANK J. CARTER.

ORVILLE HOWARD DAVIDSMEYER.

OTI-IA M. LAMBERSON.

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