US1215605A - Means for synchronizing rotary devices. - Google Patents

Description

G M" YOHKE & 6. FL, BENJAMIN.

mmms FOR SYNCHRONIZINGROTARY DEVI 3E8.

APPLICATION FlLEU AUG.21, I915.

Patented Feb. 13, 1917.

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2 SHEETS-SHEET I.

awvemtozs mkm G. M YORKE & G. R.BEN1AMIN. MEANS FOR SYNCHRONIZING ROTARY DEVICES.

APPLICATION HLED AUG-21, l9l5- Q I Patented Feli. 13, 1917.

I zsnzns-susu GEORGE M. yonxn,

NEW JERSEY, NEW YORK, N. Y., A

1,215,605. Original application filed, January 5,

on NEW YORK, 11. Y., A ASSIGNORS TO THE WE CORPORATION or NEW YORK.

Specification of Letters Patent.

1915, Serial No. 654. Divided and OFFICE- 1 ND GEORGE R. BENJAMIN O F JERSEY CITY, STERN UNION TELEGRAI?H CQMPANY, OF

MEANS FOR SYNCH RONIZING ROTARY DEVICES.

Patented Feb. 13, 19.17. this applica tion filed August 21.

1915. Serial No. 46,641.

To all whom it may concern: 7

Be it known that We, GEORGE M. YonKn, of the city, county, and State of New York, and G nonon -.VBENJA)IIN, of Jersey City, siHu'dson county, and State of New Jersey, citizens of the United States of America, Ehi, have invented certain new and useful Means for Synchronizing Rotary Devices, of Which the following isva specification, 0111.- invention relates to means for syncl'ironizing a plurality of and is particularly intended and adapted i'o'r use in soecalled syncl'ironous telegraph 01; signaling systems, though also applicable for other purposes, as, -for example-,the synchronizing of' electric generators and motors. However, since our invention is primarily intended for the synchronizing of v w distributers or commutators of multiplex o-teIegraph systems, it will be described here m as embodied in such a system, but Without a; y intention on our part of thereby limitour invention graph'systems; and While We describe here- "'2Binafter"our invention as applied to a multi- 1 plex "telegraph system of the so-called Baudbt ftyp and to a, system wherein one con ductoi' bf the line circuit is a metallic con"- ductor, e do not intend thereby to limit at "our "invention eitherto telegraph systems of fthe ueu Baudot type, or to telegraph ein one conductor of the line J a-met'allic conductor; the invention M ingtequally applicable to so-calledradio- 1 ,5" flagrant wherein current Waves are transmitted through the air or ether or other agent han a telegraph Wire. 7

T a tie av1th-Wl1ich our invention is herein illus l trated, and' clescribed, comprise two or more distributorsor commutators With'n'ieans for maintaining synchronism. Each telegraph. characterconsists of a plurality of current 'npi'ilse, (five impulses for each character, rticular system herein described),

my distinctions between the'sevactors being obtained by causing i'i'ore of the ciu'rentimpulses of each fcli a ter to be of opposite sign ordirecfit 'tion' o1 polarity from the other impulses of liar-actor; the resulting reversals of t sign affording the number of mutations necessary for the distinction of e several letters of the alphabet, punctuaconceivable that or signaling system whei (2111 a. less numrotary members,-

to use in multiplex tcle eg raphsystems such as that in connec-' means wherein each reversal pera tion signs, and special signals for the operation of the various parts of the transmitting and receiving apparatus graph systems, a greater number o'fimpulses In some teleper character than five are employed, and it is there might be a telegraph er of current impulses than five for each character might suflice. With the particular numberof'current impulses for each character, our invention'has not hing to do, being equally applicable to syst 2111s wherein. the current impulses for eacri character are greater or less in number than five.

In systems such as referi ed to it is. essential that the distributors or commutators shall rotate or move in substantial synchronisin; and heretofore, at least in the Baudot system, it has been the con provide special divisions of the commutators for effecting synchronization, tlIQtIlIlSnlltting and receiving apparatus being synchronized once inyeachcomplete rotatiomfproterm hereinafter employed, with reference to the, establishmentor reestablishment of synchronism between the tr: nsmitting and receiving apparatus). Thereby We materially increase the effective speed of transmission, and alsomaterially simplify the apparatus besides obviatingrthe otherwise numerous opportunities for er ors in, transmission and makingit possible to maintain constantly very accurate syncl ronism and to bring the transmitting and re ceiving 'a-pparatus into ccurate synchronis In, both as to speed and as to phase, very piickly, when "the apparatus is started up. i )ur invention consists, therefore, in irnpro ved synchronizing means; particular-r1 of i I line ,cur-.

I for; ,con'e'cre'nt or polarity is available of the. appation; though various portions ratus embodying our invention are adaptable mon' practice to i ceiving apparatus into synchromsm is effected otherwise than by each current reversal or reversal of polarity.

This improved correcting means affords the following important advantages:

1. Everychangeof sign of the signaling im ulses, or, in systems operating by current pu ses of one direction only, every change of current strength, provides a possible correc' tion moment.

2. At this correction moment the correcting devices will be operated if the correction is required, and will not be operated if the correction is not required.

3. As the telegraph signals consist of: various combinations of positive and negative impulses, or, in systems operating by current impulses of one direction only, ous combinations of impulses of different strength, or of impulses and spaces, many correction moments are available during each revolution of the distributer brushes.

4. Because of the foregoing characteristics of our system,'no special correetingi'mulses are required.

The objects of our invention are to mai tain accurate synchronism constantly; to avoid errors in transmission or in o eration of the apparatus due to lack of per ect syn chronism; to bring the transmitting and rean proper phase relation very quickly, when the apparatus is started up; to increase the effective speed of transmission; to simplify the apparatus employed; to make it very easy to operate the apparatus; and in general to make the apparatus relatively simple and easy of comprehension and to avoid opportunity \Ve will now proceed to describe our invention with reference to the accompanying drawings, and will then point out the novel features in claims. In said drawings:

Figure 1 illustrates diagrammatically one arrangement of receiving apparatus which may be employed in accordance with our invention, including one form of correction apparatus which may be employed.

Fig. 2 is a view similar to Fig. 1, but illustrates certain alternatives which may be employed in the correction apparatus.

Fig. 3 is a diagrammatic view illustrating schematically transmitting means which may be employed in connection with the receiving and correcting apparatus of Figs. 1 and Referring first to Figs. 1 and 311) (Fig. 3) and D (Fig. 2) designate transmitting and receiving distributers, located at opposite ends of a line circuit The two dis tributers are similar and, in general, are each divided into four each of which quadrants may be, and com- .monly is, employed for the simultaneous transmission and reception of messages, confor derangement.

of varition or correction,

other pair of rings,

similar quadrants,

"stituting, with its circuits and necessary apparatus, a single channel of communication. For simplicity of illustration, we have shown transmitting means connecte to one quadrant only of the distributer D and we have shown one quadrant only of the distributer D and we have omitted the signal receiving connections of distributer D and the signal transmitting connections of distributer D Both distributers are shown developed.

Each of the distributers D and D comprise aplurality of rings (eight rings in the construction shown) which are connected in pairs by suitable brushes, one ring of each pair being segmented and one ring 0 each pair being plain or continuous. Rings S and RG form one pair of rings, of which ring Stis segmented, these riugslbeing connected by brushes BB these two rings and their brushes'be'ing employed for receiving.

Rings S and R rform another pair of rings of'which ring S is segmented, these two rings being employed for synchronizaand being connected by Rings S and RG form anemployed for transmission, and are connected by brushes BR ring S being segmented as shown; and rings Stand HG form another pair of rings employed for the control of the automatic transmitting apparatus, and other local purposes, and are connected by brushes BR.

T, in Fig. 3,.designates a transmitter, which may be either a hand operated transmitter or may be a mechanically operated brushes BR".

and mechanically controlled transmitter,

such for example,as a transmitter controlled by 'a suitable perforated'tape. Such transmitter, in the construction shown, mmprises five sets of current reversing transmitting contacts K K K K and K or which the middle contacts are movable, and the outer contacts are connected to one or the other of two generators G and G", oppositely connected so that positive or negative impulses are transmitted according as each middle contac'tof the transmitter is in con tact with the one or the other of the corresponding outer contacts. However, the particular means for supplying current tothe line is unimportant as is the particular means for supplying current of the one sign 7 or the other to the line, as desired.

One complete set of synchronizing appa ratus is all that is required for one circuit. however many transmitting and receiving sets may be operated over that circuit. L.

a .th delay."

contact ngement shown, are both n.on-polar tion relays, one or the other being ateda'ccording as the armature of the curlingmain line relay ML makes with its upper or lower stop Relay ML controls selecting relays B R inclu- 7 Sim, through distributor rings RG and S of the distributor D Supposing a current pulse in the line wire L to reverse the posi a'tnre of tnjinof the arn relay ML, the mag net of correcting relay CL will be ener gized, but, s1nce. this relay is a delay action 1 relay, before the contact spring 78 has broken contact with the rear stop 79, a cir cuit will have been ture andnpper stop of relay ML, conductor ,79, and conductor 82 through 80 a with one of segments A S1, armature contact spring 78, rear stop I one winding oit'ithe diflerential'polar relay R, conductor 83 and the ,n'iain return conductor 81 back to battery. This current impulse, in passing through relay 1?", moves the armature that relay to t left,ythcrcby cornpl anothercircuitirom battery LB thi. gh

conductor85, the armature of relay R, a 'd conduc r 86 to distributor ring RG and vthence, through brushes B11 to one or another of the, alternated segments R and A of ring 82, Ifthe brush BR is in contact a the circuit will.

,then continue through conductor 87,switch i i the circuit will vis in contact with an A i-tery LB; Should brush BB 88 andconductor 89, the magnet of relay CL and back to the opposite pole of bat-- be in contact with an R segmentof ring at the be, instead, through co mi- 90, Sw h.

pold of battery LB. It will be seen; that the circuit path from'ring S is to relayCL or relay GL according as the brush BR of ring S or with an R (retard) segment of ring and if, (as will be the case, if the distributer vis in perfect phase relation with the distributor atthe transmitting the brush BB is over one no circuit will be completed'to either CL. The circuit through the armature of relay CL to one magnet coil 'of relay R continues for an instant only,

, asthe armature 78 of thatrelay UL" almost immediately breaks contact between spring H a duc B isdrawnbaclc to the position shown Tig; 1, by the relatively' weak holding 92 that relay,to which coil current upplied from battery LB through contors s5; {83: and- 84;.

U ontheretnrn of the armature of-relay M" o its'lower stop, a circuit is completed v completed from mainbatteryLBthrough conductor 80, the arma S8 conductor 91 and the m gnetof relay GL back to the opposite (advance) segment,

. obvious nd stop '79, whereupon the armature of throughthe magnet oft-clay OL'ij and; also, for an instant, through :he'armature, spring ii? of that relay, the back stop 79 of that relay, and conductor 93 and through the "stronger ot the coils of polar relay R back to hatt and thereby a circuit is completed from battery LB through conductor 85, the armature of relay R and conductor 88 and thence through IG bI'USl'l BB and one or he-ll. cr It segments of ring S to one oi the r l ys GL (r CL, and thence baclt to hart or, shou d brush BB be on one oi the i. latio'n divisions of ring S at the mo t of actuawion of relays CL and ii neither relay (L or relay CL will be actuated. lit-will be seen that whether relay CL or "relay CL" is actuated, depends siljnpiy upoirwlietliei' the armature of relay ML moves in one direclion or the other; that relayCL controls relay R just as relay CL controls relay it; and that when either rel'i iy It or R" is actuated to close circuit to ring RG circl it is completed to relay Cl or relay-CL, recording as brush BB ie'in. contact at the moment with an A segmentor an R segment of ring S while if brush. BI is onan insulation division of tl'iatring' S neither relay CL or relay CL will 'he actuated. v

A1 designates an electric motor driving distributor D \Vhen tilt magnet of relay GL energised, that rel iy opens a shunt circuit 9-l-----9 around a resistance BS in serieswvith the field F of the motor Afland the field resistance of the notor'being there by increased, thespeed oi the motor A? is increased. lVhen the magnet of relay CL is energized that relay l reaks the shunt 91 -97 around resistance'l is in series with vthe armature of motorA: the breaking of which shunt 96-97 throus resistance RS in serieswith the armature tlie eby decreasing the speed of the moto:- A It will be that control of the resistances RS and RS by relays CL ancl CL*, themselves controlled in themanner dc GIilJ(l, will keep distributor D in synchronism with the dis 'trib uter at the transmittingend of the line. Switch 88 is normally in the position shown in Fig '1, but may le thrown to the opposite position, to facilitlt-e bringing the distrilmters D? and D into step when starting up; "When first starting up, motor- A will drive distributer D at a speed slightly in advance of the speed'oi the distributor at the transmitting end of t1 1e line, Switch 88 when thrown to-the right orstarting position disconnects all ioffche A segments of ring from conductor 89, and connects one It segment of-distributr 82 1o conductor 91. When first starting up, mean a, not illustrated in Fig. 3, is employed to cause the transmitting distributor to send the current impulses vthroug'hthe line once only in each rotation of-that distributor. The rec aiving distributr 1) being driven. at a speed slightly 1915, wherein we have claimed broadly e t r than that of the transmitting dis? means for maintaining correction mechaw r'i ter, it will soon happen that when the nism arrangedto be brought into operation transmitting distributer is sending its curby variation of the current impulses inci- 5 rent impulse, brush BR of the receiving dent to the transmission of signals; there 70 distributer I) will be in contact with that fore'such invention is not claimed herein.

particular It segment of ring 8 then in cir- What we claim is: cuit, and thereupon relay L will be 0p- 1. In a synchronous telegraph system the, erated to retard the speed of the motor A"; combination of arotary distributer comprisso bringing the two distributors into proper ing a commutator divided into segments, 75 phase relation and synchronism as to speed. and a brush for such commutator, means he;

I The synchronizing arrangement shown in ranged to produce relative motion between Fi 2 is similar to that shown in Fig. 1, said commutat6r and said brush, two elecexceptthat the distributor D? is driven by trically' "controlled speed-varying means, a La Cour wheel PIV, the magnets DM and one'ai'ranged when operated to increase the so DM of which arealternately energized-and speed of such relative'motion, the other deinergized by the action of an electrically arranged when operated to rdecrease the driven tuning forkIFQ Relay CL controls speed of such relative motion, on f such a. shunt around resistance RS in the circuit speed-varying means connected to alternate hen the magnet of relay GL 7s energized to the intermediate segments of the commuthe shunt around this resistaiice BS is tator, and means for applyin'g current to opened, the resistance"RS being thereby said commutator brush, and for limiting the p aced effectively in circuit with magnet period of such application of current. a FM, thereby increasing the speed of the 2'. In a synchronous telegraphsystem the fork F. Relay CL operates a suitable combination of a rotary distributer comprisratchet mechanism, well known in the art, ing a commutator divided into segments, for stepping back the distributer D with and a brush for such commutator,means arreference to the distributer D"; whereby ranged to produce relative motion between 80 when the magnetof relay CL is energized, said commutator and said brush, two elec-. 5 the circuit of the ratchet magnet M is closed trically controlled speed-varying means, one and the ratchet mechanism operated to step arranged'when operated to increase the speed the distributed D backward slightly. of such relative motion, the other arranged In many cases, correction may be effected when operated to decrease the speed ofsuch 86 by varying the speed of one of the distriburelative motion, one of such speed-varying 10o ters' in one sense only. For example, the means connected to alternate segments of driving means for one of the distributers the commutator and the other to the intermay be arranged to drive that distributer mediate segments of the commutator, and normally at a speed somewhat in excess of means for applying current to said commu 40 the speed at which the other distributer is tator brush, and for limiting the period of driven, and correction may be-efiected by such application of current, comprising a retarding the speed of the faster distributer, line relay and delay-action means controlled 'or by increasingi the speed of the slower disthereby. tributer. Sincetin Figs. .1 and 2 we have 3. In a synchronous telegraph system the creasing the sp ed of the distributer I), it ing a commutator divided into segments, will be obviou that, if the distributer I) and a brush for such commutator, means be arranged to be driven normally at a speed arranged to produce relative motion beless than that of the distributer D the cortween said comm itator and said brush, two.

recting relay.,rCL and the means controlled electrically controlled speed-varying means,

thereby maybe omitted, and correctionefone arranged-when operated to increase the fected asrequii'ed by speeding up the motor speed of such relative motion, the other ar- A (Figf 1) by means of the relay CL and ranged when operated to decrease the speed the field resistance RS controlled thereby, of such relative motion, one of such speedor themes'istance RS (Fig. 2) in the circuit varying means connected to alternate segof driving magnet FM. Or, if distributer ments of the commutator and the other to D be arranged to be driven normally at a the intermediate segments of the commutas'peed reatei than that of the distributer tor, and means for applying current to said D i'e ay CL and the means controlled commutator brush, and for l miting the pethereby may be omitted anl correction ef--. riod of such application of current, and 12 fected bv means ot'the relay CL and the comprising a'line relay and two delay-ad resistance RS (Fig.1) controlled thereby,- tion relays each controlling the supply 0 or ratchet mechanism MR (Fig. current to said commutator brush, said de- This application is a division f our aplaymction relays being actuated alternately plicarion Serial No. 654, filed January 5, by operation of said line relay. v 13 20 of the driving'magnet FM of fork F, and, segments of the commutatorand the other 55 45 shown means for both increasing and decombination of a rotary distributer compris- 110 '55 t a combination of a rotary distributor compris 4. In a synchronous telegraph system the combination of a rotary distributercomprising a commutator divided into segments,

and a brush for such commutator; means arranged. to produce relative motion between said commutator and said brush, two elec trically controlled speed-varying means, one arranged when operated to increase the speed: of such relative motion, the other arranged 'whentoperated to decreasethe speed of such rel'atiye motion, one of such speedvarying means connected to alternate seg ments of the commutator and the other to the intermediate segments of the commutator, and-means for applying current to said commutator segments alternately, and

H for limiting the period of such application ofcurrent comprising a line relay, two delay-action relays operated alternately by said line relay, and two seeondaryvrelays, each controlled by one of said delay action relays; and each controlling the application =pr1's1ng a line relay, two delay-action re varying means connected to alternate merits of the commutator and the other to of current to saidcommutator segment.

, 5. "In a synchronous telegraph system the" combination of a rotary distributor compris ing a commutator divided into segments, and a. brush for such commutator, means arranged to produce relative motion between said commutator and said brush, two electrically controlled speedvarying means, one arranged When'operatedto' increase the speed of such relative motion, the other arranged when operatedto decrease thespeed ofsuch relative motion, one ofsuch speedthe intermediatesegments of the commutator, and means for applying currentto said commutator brush, and for limiting the period of such application of current'comr lays actuated alternately by said line relays,

' delay-action relay.

and; two secondary relays, each comprising a magnet coil and a 1611791111 lLlIQi'QfLWIJVlllCll is closed by the main line relay whenthat- I 1 mainline. relay actuates the corresponding delay action relay, said circuit arranged to be broken by the corresponding delay action relay'--- when it operates, each such; secondaryQr'elay further comprising means iior re turning such'sec'ondary relay to normal con "dition" upon the breaking of said. Clit'llll oi." said secondary, relay by the correspond ng 6. In a synchronous telegraph system the ring a commutator divided into segments, and a brush for such commutator, means arranged to produce relative motion between p 'trically"fe t ntrol1ed speedwary ng means, one

-arranged when ,operated Jto-,1nc rease the said commutator and said brush, two elecs speed of such relative motiomthe other arranged-When operated to decrease-the speed of such relative motion, one of such, speedsecondary relay furfiier comprisinga holding coil relatively w :aker than the saidanars net coil, and normall V energized,:-which hold ing-coil returns such seconda-ry relaystomormal condition upon ;he breaking of the r." E l circuit of said seconlary relay'byath'ec rre sponding dela'y-acticn relay; a

7. In a synchrono is telegraph system the combination of a rot try distributor compris ing a commutator divided. into segments, and a brush for such commutaton- -medns arapplication ,5 of, current 1 her: I 1

rangedto produce relative-motionibetween said commutator anc Sal-1C1" brush comprising an electric motor having-Jan amnatureand a field, means for VZI'YIIlQihB reslstance an the field .circuit connectedtoalternate seg c ments of thecommutitor,means forsvi no; the resistance in the armature circuit=tonnected to the intern]ediate seg'mentsvof the commutator, and mians- -for applying our rent tosaid commut Ltor hrush..-

8: In a synchronoi s telegraphfsystemsth combination of a rote ry' distri'bumnoon'lpr ing a commutator divided" into segment and a brush for such co mutator, Ineirnsar ranged to produce an 1 i said commutator and said-brush comprising an, electric motor hav ingan armattireaand a field, means for varying the-resistance in the field circuit connected to alternate; segments i of the: commutaton lnean's for varying the resistance in the arm itu-re circuit connected to the intermediate segments -of th mutator, and means is: applying saidcommutator bru's h,a d for'. imi period of such appl'i'c can current:

I 9 ln asynchrononrgtelegrap sys'temit e combination of a rota .-y distrihi' r comprising, a commutator -di .VllEli-ld =1il t( segments, and a brush for suclmoim v tater, nieansia ranged toproduce relativef motien between:

said commutator and s dbrlush cg. uprising an electric motor li ting-a field with esis'tance in circuit therewith and-an armature with a. resistance adapted tobeplace in circuit therewith,ja relay us ternate I segments ofth and arranged when 'actuai tocu't eifield' resistance, a relay cc namesw 1e 1nter mediate segments of the ommutator and v e motion between -trically controlled means for varying the lay responsive to tributer to the other,

'ing impulses in' said actuated to cut in the armsarranged when and means for applying curture resistance, rent to said commutator brush. ,i

10. In a synchronous telegraph system the combination of a rotary distributer comprising a commutator divided into fsegments, and a brush for such commutator, means arranged to produce relative motion between said commutator and said brush comprising an electric motor having a field with a re- 11 Im a synchronous telegraph system'- the combination of two rotary distributers to be' o1)ei',atecl in synchronisni and a line circuit connecting the mitting current impulses from the one disand for varying such the transmission of signals, for maintaining synchronisin distributers, comprising elecimpulses for and means between said speed of one of said distributers, a line itesignaling impulses in said. line circuit, and delay-action circuit controlling means controlled by that line iielay, one ofsaid' distributers .havin a commutator and means controlled by saidline relay and delay-action means for supplying current to that commutator, such speed varying means connected to certain of the segments of thatcommutator. j

12. Ina synchronous telegra h system the combination of two rotary distributers to befoperated in synchroni'sm and a line circuit connecting'the same, means for transmitting current mpulses from the'one distribnter tothe other, andforyarying such imgulses for the transmission of signals, an

means for maintaining synchronism between said distributors,- comprising -t'wo electrically controlled means, one arranged when actuated to increase the speedof one ofvs'aid dis'tributers, the other arrangedwhen actuated, to decrease the speed of such dis tributer, a line relay responsive to signalline circuit, and elay action circuifioontrolling means contro led by that relay, one of said distrihuters havm a commutator, and means controll by said lin -relay-and delay action means f supplying current to t t, nbm

of said speed varying means connected to alternate. segments .of that commutator,- and same,m'eans for transvarying means scribing witnesses. 'w

.the other connected to intermediate segments of that commutator. v

13. In a synchronous telegraph system the combinat on df two rotary ,distributers to be operated in synchronism, and a line circuit connecting the same, means for transmitting current mpulses from the one distributer to the other and for varying such impulses for the transmission of signals, a line relay responsive to signaling impulses in said line circuit, two delay-action relays actuated alternately by operation of said line relay, one of said distributers having a commutator an'c {means controlled by said line relay and delay action relays for supplying current ito that commutator, and speed varying means arranged to vary the speed of the distributer having such com mutatoi,

such speed varying means connected to certain of the segments of that commutator.

it In a synchronous telegraph system the combination of two rotary distributers to be operated in synchronisni'a'nd a line circuit connecting the.same, means for transmitting current impulses from the one distributer to the other and for varying such impulses for the transmission of signals; a line, relay responsive to signaling impulses in said line circuit, two delay action relays actuated alternately by operation of said line relay, one of said distrihuters'having a commutator and means controlled by said line relay and delay-action relays for supplying current to that commutator, and two speed varying means arranged to vary the speed ofgthe distributer having such (30111 mutator in opp cisite senses, one ofsaid speedvarying means connected toalternate segments of the commutator, the other speed connected to intermediate segments of the commutator.

15. In a synchronous telegraph system thecombination of a rotary distributor ,com-

prising a commutator divided into segments,

and a, brush for such comn'fii'tator, means arranged; to produce relative motion between said commutator and said brush, and electrically controlled speed varying means connected to alternate segments of'that com-H niutator; and means for a lying current-to said commutator brush, an or limiting the period of such application ofcur-rent, comprising a line re ay and delay' action means controlledthereby. In' testimony whereof we have signed this s ecification in the. presence of two subsome YoRKE,

U GEGRGE R. BENJAMIN. Witnesses: a

FIX-S. HUNT, R; J. MEIGS.

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