US143341A - Improvement in multiplex or interval telegraphs - Google Patents

Description

3Sheets-Sheet1. M, GALLY. Multiplex or Interval Telegraphs. N0. 143,341, -Patented September30,1873.

SSheets-PSheietQ. M GALLY.

Multiple'x or Interval Telegraphs. No. 143,341, Pat'entedSeptemberSO,1873.

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Mul No. 343,34.

UNITED STATES PATENT Olsrrcn.Y

MERRITT GALLY, OF ROCHESTER, NEW YORK.

IMPRQVEMENT IN MULTIPLI-:x `QR INTERvAL TELEeRAPHs.

Specification forming part of Letters Patent No. 143,341, dated September 30, 1873; application filed V September 11, 1873.

ful Improvements in Telegraphic Apparatus,

and I do hereby declare that the following is a full and exact description thereof, reference being had to the accompanying drawings and to the letters of reference marked thereon.

In the drawings, Figure lis a plan of a number of the devices with circuits arranged for a multiplex instrument. Fig. 2 is a `front view of the tripping-escapement; also, the re# volving circuit-closer. Fig. 3 is an end view of vibrating paper-cylinder with type-wheel andmagnet. Fig. 4 is an elevation, showing magnet with automatic returner for armature 5 and Fig. 5 is a plan of same. Fig. 6 is magnet with rotary indicator. Fig. 7 represents the-mechanism for controlling the key-movements. Fig. 8 is a plan, showing the arrangement of conductors for forming a telegraphic alphabet by a series of combinations 5 Fig. 9, diiferent methods of constructing magnets; also, a group of magnets operating in connec tion with a single armature. Fig. l() represents devices for an electro-chemical register. Fig. 11 represents a partial gear for securing interval movements to type-wheel or papermotor. Fig. l2 is a front view of partial gear, showing a means of adjustment; and Fig. 13 is a plan, representing aline of instruments arranged according to my multiplex system, the circuit-closers being each shown with one group of transmitting-conductors, corresponding to the plan of Fig. 8, and also showing the relative positions of the receiving-conductors, the Y instrument-circuits', the main line, and line-pulsator.

I. By examining the telegraphic alphabet in common use, which is made up of dots and dashes, either recorded by a register or readby sound, it will be found that the entire length of the longest character (the period, for example) occupies the length of fteen dots, and that, by

omitting some of these dots and joining others in combination, any of the letters, numerals, on `punctuations may be` formed. In or` der, therefore, to produce the letters of the alphabet for telegraphic transmission by a set of keys, each key representing an entire letter,

I use fteen short conductors, G6, for instrument circuit-closer, as shown in group E, Fig. l, and, by means of the operating-keys A, B, C, Src., make connection of the circuit only through such combinations of the conductors of the circuit-closer as'shall produce the letters represented by such keys as the connector of the circuit-closer is passing in contact overits conductors. In order tosecure the proper connections of [the circuit only through the proper conductors for each letter, I proj ect irom 4the fifteen conductors, group E, Fig. 1, fifteen metallic lines, U, passing them under the key-bars, as more clearly shown in Fig. 7, in which the key representing the letter A is shown.` As the key-bar is depressed by forcing down the key, such key-bar will come in contact .with the four small spring-wires which project from four of the metallic lines U. The office of these spring-wires is simply to insure contact of the bar with the proper niunber of metallic lines, the four representing the letter A, as will be seen by referring to the diagram E4,

Fig. 8. Different numbers of such spring-wires lie under the diiferent key-bars, each key connecting with such a number, and projecting from such of the metallic lines as shall produce its particular letter as the circuit-closer ,is making a movement over the group of conductors E of Fig. l.

II. In Fig. l the circuit-closeris represented as having four segments, each segment contain- 'ing a group of transmitting-conductors. These segments are reached at different times by the revolving connector D; and it will be seen that, if four manipulators were connected each with a particular group or segment of conductors,all could transmit through a single main-line wire withoutconflict, onepart of suchmain line connecting with the key-bars of the severalmanipulators, andthe other part of the line corresponds to the conducting-bar of diagram E4, Fig. s.

I have arranged the circuit-conductors in Fig. Al in plan view for better illustration, although they may occupy the periphery of a drum, as shown by E2, Fig. 2, spring-connectors being shown at D2.

`Although different instruments maybe made to transmit messages upon a single wire without conflict by being connected with different segments of an automatic circuit closer, or even different instruments at diiierent stations may accomplish the same by using different circuit closers running synchronously, each instrument having its particular segment, nevertheless it will be clearly seen that such a system of multiplex telegraphy77 would be impracticable. The number of instruments on the line would necessarily be limited to the number of segments employed, or different stations would be obliged to. give up intervals to other stations, when required, leaving many instruments unemployed, as in the common System' t '.lhe part of my invention which I am now to describe doesl not consist in giving to an strument, by any construction of devices, a particular interval of time on which it may opcrate, and conning vit to such inteiival; but it consists in such a construction ot' instruments as shall enable thel operator to setl his instrument to any unemployed interval, either for transmitting orl receiving; also, to beable to ascertain what intervals'fare and what are not being employed by other instruments; also, to, set his instrument to transmit on one interval and receive on another, or a numberof others, as he may desire. This enables any station having but one instrument'l to communicate with any operator of a station having fifty struments, and allows him'to know at once 'without call whether he use one of theintervals for his communication. It also enables any one of the operators at the large office to know immediately whether all the intervals of the line are occupied, and, by means of a particular intervallet open for calls, to be always in communication with every office on the line, and to secure the` attentionl of any operator on the line when it is important so to do.

I will particularly describe the devices shown in the drawings for accomplishing these results. as follows, although they may bel greatly modied, and I do not intend to. be limited as to the particular means I shall employ. In Fig.

l an interval-switch is shown at U3. rI he lines" lying'l underneath theA part of theA switch nearest its pivot represent conductors, with'which the switch, by a set of spring-connectors, remains inr contact. The conductorsi with which thesesprings connect should equal in number4 the iifte'en metallic lines U, and connect therewith, as partially shown. The two radiallines of dots o n each side of the switch U3 represent conductors, eachlinc corresponding in number to oneof the groups of transmitting-conduct! o rs of the circuit-closer, and vconnecting there:- with, as partially shown. The switchis provided with iifteen more spring-connectors upon its under face, each one of which has connection with one ofthe fifteen rst mentioned, all the pairs being insulated from each other. It will be seen that, if the switch U3 be turned onto any one ofthe radial lines of conductors, it

will connect the key mechanism, through the metallic lines U, with one of the transmittingsegments of the circuit-closer; also, that the key mechanism may be connected with any one of the segments at willby changing the switch from one radial line to another, and thus be set to the different intervals of transmission.

The instrument having thus been set to transmit on any desired interval, the remaining intervals, 011e or all, may be set for receiving messages from other stations, or maybe given to any other instrument on the line for transmitting or receiving, as the case may be 5 and I will now describe the method and means for ascertaining whether the other intervals not being used by the transmitter are employed 0.1 unemployed,

and, if unemployed., how t0 Set any 01.1,@ 0r all of them t0 receive the, particular message 0r messages intended for such station. The eX- ternal'ring of the circuit-closer, Fig. l,is divided into, five sectors, fonr of'which` 'corre- Stond will. 011e transmittngfseglnentsaud rep.- resent the receiving-conductors. The small segnfientl at D is given to the -line-pulsator for The dotted, line from each of the four receiving-sectors of the circuit-closer leads to one of thefour switches of the groupl shown at N, and represents metallic connection between the switches andthe sectors. These switches set the circuit-closer to the interval or intervals upon which the instrument is receiving. Four conductors,` c, corresponding with the four switches, connect with a line leading tothe receiver M, as` shown; or each of these conductors may connect with a separate receiver, if desired. The four conducting-pointsof the bar N are connected with the main line coming in at the binding-post I. This part of the main line also connects with the receiver M, asshown. If any one of the: switches of the group is turned onto its lconductor e, it will connect its receiving-sector of the circuit-closer with theregister, and any message passing on the main line during its interval will passfrom the binding-post I through the receiver M; thence tothe receiving-switch, which is set to such receiver; thence to` the receiving-sector for that interval; thence to the interval metallic` ring; and thence to the binding-post J, onto the main line. It" the message. is coming from the opposite direction, it takes the same path from J to I. All the instruments on the. line or branch lines set upon this interval will receivey the, same message. Any operator may let it pass by, however, by turning the receiving-switch for that interval ontoits conductor of the groupvN, connecting directly with the `main line, without allowing the messageto pass throughthe receiver; or the operator may stop the message for. that interval by connecting.

tripping the circuit-closer and connecting its his ie@raving-.linefor that interval with the groimd. This will not interfere with messages passing on other intervals, as the sector for this interval is cnt out, while the circuit-clos: ingconnector is passing other segments. The

transmission, its receiving-switch is turned i both from the-line and receiving-circuit. This breaks the line at this instrument for that interval; and after setting the transmittingswitch U3 to the interval, the path of the cirl lcuit can only be through the operating-keys to the key-bars from I, and, if any of the key-` bars are depressed, giving its proper pulsations through its segment of the circuit-closer; and thence to J. When any interval is not being used by the instrument for transmitting -or receiving, the transmitting-switch U3 should not connect the manipulator for that interval, and

the receiving-switch for the same interval i should be turned onto its conductor N of the main line. All the switches may beset thus,

and the entire number of intervals be given to other instruments on the line.

It will be seen that the instrument may be constructed with any number of segments in the circuit-closer, and any number of switches to correspond, thus securing any number of intervals, and as many operators can be employed l upon the line simultaneously as the capacity of recording -instruments will allow. With electro-chemical recorders the number may be very great.

III. I now pass to the third part of my invention, which has reference to the key mechanism. i

It willbe seen that, if the manipulator were not cut out from connection with the circuit-closer during all the intervals except the one to which it is setfor transmission, the depression of a key during any of the intervals Y given to other instruments or to the receiver would conflict with other messages. This would be in allcases of attempted transmission unless the segments were separated from each other a sufficient distance toy allow the operator to depresshis key during Vthe passage of the circuit connector over thel space just preceding the transmittingsegment to be used; and if the key were worked during its transmitting interval, it might not transmit the entire letter desired. Magnetic locks have been devised for holding operating-keys during their proper time forl transmitting contact, and a signal click or bell to inform the operator when to depress a key and when he must not; but such devices must, of necessity, occasion very slow and deliberate manipulation, the constant watching of signals taking the mind of the operator from his message, and giving rise to many mistakes and misstrokes. The third part of my invention provides against all such defects, first,

by allowing the operator to strike a key at any time, securing its effect only at the proper instant; and, secondly, in allowing the key to be depressed quickly or slowly, occupying any portion of the intervals given to other instruments for transmitting contact, or to the receivers of the line. If the key be struck at the time it should be in transmitting contact, it cannot be depressed, and will not yield until the interval is passed, when it will be ready for the interval when it next occurs.

I will particularly describe the devices for securing these results, as shown in the drawings; but, as they are subject to various modifications, I shall not limit myself to the peculiar construction shown.

'The receiving-switches, with their lines connecting with their receiving sectors of the circuitcloser, have another office besides that already described. I previously mentioned the fact that,when the instrument is set to trans.- mit on any interval, the receiving-switch for that interval should be turned both o om the main-line connector and the receiver. It may now be set on one of the conductors d. The receiving-sector for the interval which is set for transmission now becomes a part of the transmitter, and is used in connection with the conducting-ringnext within the circle to connect the circuit of a local battery to affect a magnet, U8, situated under the key-bars, as shown in Fig. 7. In plan, Fig. l, the circuit will be seen to lead from the switch and conductor d, entering the instrument at a7. It

then passes to the magnet nnderthe key-bars; l

thence to the local battery provided for this eircuit; thence back to the instrument through a, to its ring-conductor of thecircuit-closer; and thence back through the sector to the switch, completing the circuit. While the circuit-con nectors of the circuit-closer are lpassing the transmitting interval, thel magnet U8, Fig. 7, is charged by the local battery, and attracts its armature. The lever 7 is attached to the rocking bar 8, which lies under all the key-bars, and, while the magnet U8 is charged, the stop l0, which is pivoted to the armature-lever, is

thrust under the lever 7, and prevents the depression of any key while the armature is thus held by the magnet. There is no magnetic lock for holding a key down after being depressed, nor for preventing a second one being worked before another has accomplished its object, the devices for such purposes acting automatically. The rocking bar 8 rocks on its pivot at B', and, when a key is depressed, the lip 9 of the bar turns to a position under all the remaining key-bars, preventing their being worked until the operated key returns again to its first position. As the circuit-elosers of the manipulator are cut out from the circuitlines of the revolving circuit-closer of the instrument on all intervals except the one set for transmission, it will be seen that the operating-keys may be safely struck during any of the intervals, and, if depressed before the time arrives for transmission, it will only be tact.

same time it lpasses under the remaining bars.

The depressed key-bar remains in its position; Y uni il it has accomplished its transmitting contact, when lthe recoil of the armature-spring ofi the armature-lever, which has been used to, work the stop l0, trips the catch Dl by means `first and third, they vtogether produce two of a thruster, E1, as shown.

It will be seen from the foregoing description, that if the instruments are constructedy for fourl intervals, any four of the operators on the line may be simultaneously employed, and each will have three-fourths of his time for operating his keys, only one-fourth being used for their transmitting contact; or, if the instruments be arranged for iifty intervals, with electro chemical recorders, fty operators would be employed, and each would have forty-nine iiftieths of his time for his downward strokes. The instruments might be run asrapidly as the operators could possibly finger their keys, and still no mistake orcollision as to time could occur.

IV. The fourth part of my invention has reference to an interval for calls, through which all the operators on the line can always be in com- To accomplish this object I select a particular switch of the i group N of each instrument, and mark it for calls,7 or have it understood as such by all the 3 I connect with this switch a sepa- 1 rate receiver from the one or more used for messages; and if a soimder be used for this purpose, I give to it a peculiar quality of tone, Q

munication with each other.

operators.

differing so much from the sound of the other instruments as never to be confounded in its strokes with those of other Sounders. I now keep allthe -instruments of the line turned for this interval onto the call-receiver, unless any particular operator Wishes to send a call, when l he, for the moment, turns on his manipulator, and all the offices on the line receive his call. Thus, all the offices are in constant means of communication, at least on one interval, and, in case of necessity, can call for any other interval to be given to any operator. In an unemployed instrument, all thev switches are turned onto the line except for the call-interval, which is on its receiver. If, now, the operator wishes to know whether there is an unemployed interval which he can use for a commiuiication, he turns the several switches, one after' another, onto his receiver, until he finds yone interval on which the receiver will not respond. I He immediately turns s uch switch both off the line and receiver, and he has broken the line at his linstrument for that inter-val, and it is secured tohim for his message. IIe then signals the station with which he wishesn to communicate through'the call-'ia .terval, giving the number of lthe interval he has-secured; and if such station'has an imemto a combination-key. This is shown Fig..

8 at G2. This key isa combination of four minor keys, vas shown, which may be struck in 'dierent combinations, for producing the elements of they dot-and-da'sh alphabet. The four key-bars connect with four of the conductors 'of the vgroup E4. If the first fone be struck, it WHL-therefore, produce a dot; 'if 'the dots; if the iirstfsecond, and third, they will produce a-dash;l 'and if l'the iirst, third, and fourth be struck together, they will produce three dots. This key may be used for the inanipulator, thus making the segments of the circuit-closer lmuch smaller, only having four conductors to each; yor .it may be lused 'to advantage as afcall-key,'thus making the call-interval much shorter. The third and fourth conductors of the small group should beseparated by a space; or, lfor illustration, coimt on the diagram E4, Fig. 8, 'the first, second, third, and iifth, and you have the. group of four in proper position.

VI. The-sixth part of vmy invention has reference to the correction at certain intervals of the circuitclosers 4of the line as to unison, without necessarily retarding, or stopping, or changing., in any way, the speed of the motors'. Near the revolving circuit-closer is a magnet, H, which is affected by a main-line pulsator,7 which passes a strong pulsation through the line while the circuit-connectors of the -circuitcloser arey occupying .the short segment at D. The lever G of the armature of the magnet is provided with a lifting-cam andas the-'circuitconnector D reaches this cam, a spring-latch upon the surface of the connector, provided with a tooth passing through the body of the connector, -connecting with the vtoothed wheel F, as shown in Fig. 2, is lifted by its contact with cam of lever G,and, the tooth being freed from the toothed wheel, the circuit-connector is tripped at this point, having no driving power. The motor moves the wheel F, and is not affected by the tripping of the circuit-connector. When the line-'pulsator kcharges the magnets H of the line, all the armature-cams are withdrawn, the Vcircuit-closers are again connected withgthe motors, and make another revolution. The additional friction of the bearings of the wheel F, whenthecircuit-connector is tripped, is made to, as nearly as possible, balance the power required to drive the connector. The motor remains, therefore, unaffected by the vcorrections of thecircuit-closer. The connections may be made less frequent by gearing backward from the shaft of the circuitconnector, vand making the latch to connect with slower gear. l

VII. In circuit-closers made ofconductors with `dust maycollect upon 2these bearings, and still ors.

. ductors.

illga 4segment alone V,and yin this interveninggnon-conductingmaterial, if the connectors are allowed to have a bearing `upon the non-conducting substance, a metallic dust soon collects, and the insulation of the conductors is soon imperfect. If the conductors are made? Ato project from the surface,and the connectors are not allowed to have a non-,conducting bearing, the `friction of the circuit-.closer is variable, 1and -theconneotors are liable .to catch in their vmovement.

-To avoid these `difficulties I place the con-` nductorsin a trench. They are then surrounded L 4entirely by an open space.` I `make the connectors wide enough to have abearingat' their yedges upon the nonconducting material at the ysidesof the trench. Any amount of metallic not make any` connection between Itheconductshown as having such trenches for its con-g VDI. lSheetoffthe drawings, designated-as Fig. 13,shows therelative positionsofthe receivf ing and transmitting segments, which are seti for illustration-upon certain intervals, for transmission, ,or for receiving. The receiving-conductors correspond in position on the circle --with the transmitter from which it .is receiving. j .Each segment of each instrument has both transmitting .and receiving conductors, differ` as will be seen from the foregoing descrip-.1 tion, as to numberand form. Conductors ofthe line, in the plan, Fig. 13, all cut out bythe adjustment. Remembering that ,all the circuit-,connectors of the line are mov-1 ing in unison, `orare at least upon correspond-i ing segments, the intervals of the line may be traced out, and it will be `found that the message from station l is being received at stations 2 and 4; that tom 4 received at l,and that; from 2 received `at 3. A5 represents the maini line.; F6 the ground, and D4 the line-pulsatonf The switches of the Iinepulsator are toturn .the currentoi the line off or en. The short may connect with tho line' case the instruments may be kept regulated while the main `battery is thrown off for all `other intervals, which will allow business to be done between near stations of the line with local batteries with- .out using the main battery. Any intervall may thus be cutout from the main battery when desired, and thusconsume less batterypower.

IX. Theninth part ofmy invention,on whichI Shall make claim, `has been fully described in connection with the foregoing explanations.

It hasbeen found dicul't to secure strong` pulsations to thearnraturelof a magnet, and, at the same time, have such .pulsations rapid. AIt requires time for the `core-of a magnet to become charged,and then it requires .a certain amount of time for it to lose its magnetism. The time ,required to charge va magnet is in Vproportion to its size, the time differing in proportion to the squares ofthe diameters of the The circuit-closing E2, Fig-2, is`

The operatingasadjusted, are shown s the others having been 1 .cores. "A small magnet `is therefore charged `quioklys but it is proportionately voo-kln lorder to affect the armature s quickly, and still with great power, I use a group of small magnets, each acting upon the armature withquick effect, while all together` give the power required. The circuit-wire may connect with each magnet separately, or pass from one to another, asshown Ein Fig. 9, H2. lin-any broad sense this is not acombination-magnet, Aas each .small magnet exerts its own independent power .upon the armature. There is, however, another advantage in. grouping lthem together, if `not too far separated. Itis the Amutual induction caused by such position.

. Toproducestillmore rapid-magnetic-pulsations `Iuse a number of electro-magnets, such as previously described, shown at V1 V2 V3`7 Fig. V5, 'a side view of lone with its positivelyreturmng armature being shown in Fig. 4.

i The wheel Z is ldriven bythe motor of the instrument, and in unison with the `circuit-closer. .To oooh.magnet-io.givenooirouit-oonnootor, o3, connecting with a conductor on one-third of the peripheryof the wheel Z. `The armatures Y are counterpoised, so that the least power of the magnets will cause lthem todrop. VThempulses which `pass the circuit must .affect the magnets successively as the wheel Z turns on ,its axis. 'A cam, S, is placed `.upon the-under face of the wheel Z; and, if anyone of the ,armatures is Vcaused to drop by its magnet, the oam strikes the armature-lever, and gives-ita positive return movement before the power of the magnet is 4diminished enough to be overcome by a spring or the like. The wheel, driven very rapidly, will thus record, `by the return movements ofthe armatures, very-rapid electric pulsations. ne of the magnets is be- .ing aiiected while another is losi g its magnetism, and so on. c

XII. Fig-6 shows a magnetic indicatorfor the lreceiverwhenoperated byveryrapidpulsations, which is very sensitive, not only `to rapid pulsations, but to those electric pulsations which are veryweak. It is constructed of a wheel, T, which maybe very carefully balanced and hung on iinely-jeweled points. All illdicating- .scale is shown marked upon this wheel, V,and a pointer to indicate how far it fturns at each movement. The wheel X is covered with hairs of fur, or `ne silk, or the like. This wheel is driven by a motor, and the ne hairs turn the wheel T by very light frictional contact, which is easily overcome bythe slightest e'ect of the retarding-magnet shown below wheel T, and placed very near to its periphery, the rim of the wheel being made of soft iron. 1f the pulsations through the circuit ,are not too rapid, their lengthmay be easily read bythe means of theseal and pointer, and their num- -ber counted. If, however, the electric pulsations are too rapid for such reading, 'I use two magnets, as incase of Fig. 5, :and also three wheels, T. I make the wheel X to correspond to the wheel Z, with conductor and connectors for the magnets acting in rotation. ll have now divided up the impulses among'the other mag- I give the wheel X the time of a dash for its revolution. If the first Wheel of the order makes a stop, it is a dot; if the third next stops, it is a second dot; if the first succeeds the first, it is read a dot, a space, and a dot;77 and if the entire number stop, one after the other, apparently together, it is read as a dash. In this manner very rapid and very faint electric pulsations can be made to indicate properly, and be easily read.

XIII. By examining Fig. Lit maybe seen that the duration of the return movements of the armature will be in proportion to the incline of the cam or cams S acting upon it. If the cam be long 4and its incline gradual, the return movement will be lengthened thereby. A circuit is shown passing into the support of the armature lever to a connector, which, during the return movement, closes the circuit, with a line passing into the shafts of wheel Z. Thus the short pulsations of the magnets may be repeated by pulsations corresponding to the duration of the return movements of the armatures, and caused thereby.

XIV. In a multiplex instrument using only certain intervals for its receiver, it is desirable that the paper should move only on the receiving-interval. To accomplish such result, I either slip or connect a gear for the movement in the register by means of a local circuit arranged with the circuit-closer for the receiv-v ing-interval in similar manner to the local keycircuit for the transmitting-interval; or I use a partial gear, comlected with the motor. Such partial gear is shown in Figs. 11 and 12, the wheel M2 being the driver, and the wheel L2 `connecting with the paper-motor. The different intervals occupy different portions of the spaces between the teeth of wheel M2. The

'device is set to its proper interval as follows:

An extended hub or thimble is shown on the wheel M2, Fig. l2. This hub has in it a diagonal slot, in which is a pin entering the shaft. The wheel and hub are loose on the shaft, which may be moved to the right or left by moving the shaft longitudinally, so as to cause the pin to take the positions in the slot represented by the dotted lines. The relative positions of the gears will be set to any of the four intervals.

XV. In similar ways and with similar means I give to a type-wheel its revolution on the proper interval to which it is set.

I f a printing-register is used, it should also be understood that the number of conductors in each transmitting-segment of the circuitcloser should be equal to the number of char- 1 acters upon the type-wheel, and that each operating-key should connect only with one of the group representing the letter indicated by `the key.

XVI. The sixteenth part of my invention, on which I shall make claim has already been fully explained in connection with the operation of other parts.

What I claim as my invention, and desire to secure by Letters Patent, is

l. An automatic circuit closer having a group of conductors representing the short dashes of a telegraphic alphabet, and sufficient in number to fill a space equal to the length of the longest letter of such alphabet, in combination with transmitting-keys, each key connecting with such a selection or combination of the conductors of said group as to produce any letter of the alphabet indicatedby such key.

2. In a line of instruments arranged for multiplex transmission by allotting to different instruments different intervals of time for operation, the combination, with a transmitter or receiver, of devices for changing such transmitter or receiver from one interval to another, thus setting the instrument to any unemployed interval desired, substantially as specified.

3. A transmitter having in connection therewith an automatic circuit-closer with an interval-circuit, cutting out the transmitter during the intervals not allotted to it for transmission, in combination with devices for allowing the working of the operating-keys during an interval or intervals allotted to other instruments, and holding such key or keys until their proper interval of transmission has arrived, substantially as specified.

4. The combination, with a line of multiplex instruments, of call-receivers, arranged upon a given interval or intervals, allowing all the stations of the line, or any part of the line, to be in constant communication with, each other, for calls or explanations, without interrupting the message-intervals, substantially as specified.

5. The combination-key G2, in connection with its conductors, substantially as specified.

6. The magnetic latch-escapement G d D F, or equivalent, for tripping the circuit-closer and correcting its time of revolution without affecting the motor.

7. A circuit-closer made of .conductors separated by non-conducting material, having nonconducting bearings for the connector or connectors, which bearings are separated from the conductors by intervening trenches, substantially as set forth.

8. In combination with an automatic circuit-closer, a receiving conductor or conductors, .occupying a space equal to a group of transmitting-conductors, from which group combinations are made for producing different characters. Y

9. The combination, with a transmitter and receiver arranged for a multiplex system of intervals, of devices for securing one interval to the transmitter while another is being used by the receiver, substantially as set forth.

10. The combination of an armature with a number of magnets operating therewith, substantially as specified.

11. The armature of a-magnet, in combination with a device which applies positive mechanical force for the return movement ofthe armature after it has been attracted by the magnets, substantially as speciled.

12. A magnetic yindicator consisting of a Wheel moved by slight friction-power, and stopped or retarded for its indications by means of a magnet.

13. The combination, With a telegraphic transmitter or receiver, of a relay or repeater, which gives its repeated pulsations by means of the return movements of its armature, Which impulses are measured by the duration of such return movement, substantially as set forth.

14. The combination, with a register, of devices for ,setting the same for movement of the paper at appointed intervals, corresponding with the intervals on which it is to receive,

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