US936140A - Telegraph system. - Google Patents

Description

W. LEIVESLEY.

TELEGRAPH SYSTEM.

APPLICATION FILED AUG. 7, 1906.

936,140. Patented 061;. 5, 1909.

3 SHEETS-SHEET 1.

ff we #ffl S14/m1014160@ awo @HJM/14,09%# .A M @r @li/meg@ W. LEIVESLEY.

TELBGRAPH SYSTEM.

APPLICATION FILED AIIGJ, 1906.

936, 140. Patented Oct. 5, 1909.

3 SHEETS-SHEET 2.

ANDREW, a Gamm eo Pnomunwenmms. wAswNaIDN. n c.

W. LEIVESLBY.

` TELEGRAPH SYSTEM. APPLICATION ljlLBD AUG. 7, 1906.

Patented 0015.5, 1909,

3 SHEETS-SHEET 3.

m, n m w ausw4 a mum cm PHoTn-LITHOGRAPNENS. WASHINGTON. n c.

"UNITED STATES PATENT UEFIQ.

WILLIAM LEIVESLEY, OF SPRINGSURE, QUEENSLAND, AUSTRALIA.

TELEGRAPH SYSTEM.

To all whom it may concern.'

Be it known that I, IVILLIAM LErvEsLEY, a subject of the King of Great Britain and Ireland, residing at Eclipse street, Springsure, in the count-y of Denison, in the divisional district of Leichardt, in the State of Queensland, Commonwealth of Australia, have invented certain new and useful Improvements in Telegraph Systems, of which the following is a specication.

This invention relates to telegraph systems and combinations of apparatus used therewith.

In its broadest sense this invention comprises a system of switching and repeating, and although in regard to the purely instrumental parts, existing apparatus and 'well understood theories are used, it is peculiarly apart in its combination, arrangement, and working from other systems.

The object of the invention is to provide circuits and a simple combination of apparatus and switching gear to facilitate the transmission of messages direct to their destinations, over long lines and in a variety of directions, to permit any prearranged number of telegraph circuits to work with each other just as though they were all on one and the same circuit; to enable a number of stations on different lines, not ordinarily in direct communication, to communicate directly with each other without hand repetition. In newspaper messages the same news may be transmitted direct to its various destinations by one telegraphist by one operation of a telegraph key. This invention also allows of signaling four or more ways on the Morse system and at the same time may embrace or combine other systems. It provides for repeating direct on to main lines and different systems are enabled to work together and interchange signals harmoniously.

Other objects and advantages will be in part obvious and in part pointed out hereafter. But in order that this invention may be more fully understood and made comprehensible to those skilled in the art, diagrammatic drawings illustrating the same are appended as a part of this specification.

Figure 1 shows a cross-bar switch board in side elevation and partly in section. Only two of the lower bars are shown for convenience of illustration. Eig. 2 shows a repeater operating in accordance with the usual well known theories and is for work- Speccaton of Letters Patent.

`Application filed August 7, 1906.

Patented oct. 5, i909.

Serial No. 329,578.

ing four or a lesser number of wires or lines and is'capable of being reversed at the repeating station for transmission in the opposite direction. Eig. 3 illustrates the system indicated in Fig. 2 more particularly and is meant to'show clearly the working parts in simple form and how the arrangements shown in the said Fig. 2 act. Fig. t shows an automatic combined repeater' for working four or a lesser number of wires or lines and is capable of working in either direction withoutthe need of an attendant to perform any hand switching. Fig. 5 illustrates the system indicated in Fig. 4, more particularly and is meant to show clearly the working parts in simple form and how the arrangements in the said Fig. a act. Fig. 6 illustrates how the ordinary Morse line relays and the lines connected therewith may be connected by means of the switch board for the simultaneous working of all the lines so associated. A

On further reference to the drawings it will be seen that the switch board comprises metal bars 11 placed across each other'. The upper bars are hereinafter called the upper series and the lower bars are hereinafter called the lower series. Between the upper series and the lower series is placed insulating material 12 (Fig.'1). At the crossing or point of intersection of each of the metal bars is a plug hole. The plug holes in the upper series are marked 18. The plug holes in the lower series are threaded as shown in Fig. 1 and marked 14. At each end of each bar is a terminal screw 15 and between the outer ends of each bar and its fellow are bridging connection spaces 1G to unite any bar of the same series to the next adjacent bar. By varying the connect-ions of bars at the crossings or points of intersection by means of plugs and between the ends of the bars a variety of combinations may be made and the arrangement of any lines connected to the switch board may be diversified.

In combination with the foregoing two classes of plugs are used The first is a screw plug for connecting a bar of the upper series with a bar of the lower series and consists as shown in Fig. 1 of a milled knob or turning portion 17 composed of ebonite or similar insulating material and having below the same a head and a shank. The head is marked 18 and beneath it is a shoulder 19. The shank 2O is threaded as at 21.

The second class of plug has an entirely llO are marked at 43.

plain and preferably tapering shank. lt may be, however, of any suitable character, and is marked 22, (see Fig. G).

F 2, 3, 4 and 5: These figures indicate a combination of two systems of repeating apparatus with a simple means of using either one or the other as circumstances require. The change from Fig. 2 to Fig. 4 is effected by the placing of switches and plugs in the positions hereinafter described. The numerals 1, 2, 3, 4, in these figures represent telegraph lines earthed at distant stations (Morse systems). The plus signs show the positive lines or wires, and the minus signs or hyphens the negative lines or wires. The turning portions 17 of screw plugs indicate where a bar of the upper series is connected with a bar of the lower series. From the switch board extend four lines as shown. These communicate at 23, 24, and 2G with the four segments of a four way plug switch 27. From each segment a line is led to threeway plug switches marked 28, 29, and 31 respectively. From one of the segments of i each of the three-way plug switches isled a wire to earth at 32, 33, 34 and 35. rlhe relays 36 have the usual magnets and armatures with spring retraction and are inlluenced by main line currents. The armature Contact points of the relays are marked at 37. Transmitting keys with circuit closing switches attached are shown at 38 and are for use of local attendant to t `ansmit his own stations messages if desired. Galvanometers or current detectors are shown at 39. Manual switches are marked at 40. Plug holes at 41 ai'e for admitting local Sounders with their local batteries. Local sounder batteries are marked 42. Local sounders For bridging contact points of the repeating transmitters or allowing same to be operative plug holes at 44 are provided. The contact points of the arma` tures of repeating transmitters are marked at 45. The repeating transmitters 46 have the usual magnets and armatures with spring retraction. Plug holes 47 are to make or break local relay armature contact point circuit. rlhe local relays 48 have the usual magnets and armatures with spring ret action. rlhe contact points of armatures of local relays are marked at 49. Local batteries are marked 50. Plug holes to make or break local circuits are marked at 51.

It will be observed that the above instrumentalparts all appear on both the right and left hand side of the apparatus, and the parts will, for convenience, be hereinafter referred to as either right hand or left hand dependent upon the side of the apparatus being referred to.

Fig. 2: In the condition as shown in the drawing Fig. 2 is arranged to repeat automatically in four directions on telegraph wires earthed at distant stations. then arranged as shown, the apparatus requires an attendant at hand to attend to the manual switches to suit the requirements of distant stations. rlhe right hand relay 3G is in condition to receive currents and signals from lines 4 and 3 and its armature which makes contact at 37 is in condition to repeat. Assume a key to be open on line 4 the right hand armature contact point 37 would stand open as shown. lVhen the key alluded to be closed however, a current passes through the apertures from line 4 through the bar of the lower series connected thereto, through the connecting screw plug marked at 17 and outwardly along the first bar of the upper series and line connected thereto to 26, thence through the three-way plug switch 30 by means of the plug shown therein, via line to the left hand and closed manual switch 40, to right hand galvanometer 39 and key 38, right hand relay 36 whose armature makes contact at 37. The current passes through 44 on the left hand side by means of plug shown therein, through three -way plug switch 29 by means of plug shown therein, along line to second top bar of upper series, through connecting screw plug therein marked at 17 to bar of lower series line 3. So far it will be observed lines 4 and 3 are in direct communication. It will now be shown how currents and signals are conveyed to the lines 2 and 1. Contact at 37 having resulted from the current through magnet of right hand relay 36 a current would pass on the lines 2 and 1 from line 2 along bar of lower series connected thereto through connecting screw plug marked at 17, along bar of upper series and line connected thereto to 24 thence through threeway plug switch 28, right hand local sounder 43 and battery 42, through right hand relay armature contact point 37, right hand local relay 48, left hand galvanometer 39 and key 38, to left hand relay 36, through 44 on right hand side to and through three-way plug switch 31 to 23 along line to bottom bar of upper series, through screw plug' marked at 17 to bar of lower series connecting line 1, and then to distant stations. 1n consequence of current passing as described all four lines receive signals at each movement of any key on lines 4 and 3. There is a` further result in the apparatus locally. A current passing through magnet of left hand relay 36 attracts the armature to contact point 37. This action forms a local circuit from said left hand contact point 37 via left hand local relay 48, closed switch 40, left hand local sounder 43 and battery 42, back to the Contact point. The current in this local circuit from the battery 42 operates through magnet of local sounder 43 whose armature is audible locally. (The right'hand sounder 43 is not audible by reason of right hand manual switch 40 being open). Now should any station on lines 2 and l require to transmit signals to lines 4 and 3 the telegraphist at such station on line 2 and l would break circuit by opening the key switch, when signals 'from the opposite. line 4 would cease to be recorded on left hand sounder 43. Under such condition the local attendant would close right hand manual lswitch 40 and open the le-t hand manual switch 40. lVith switches now in this condition any station on lines 2 and l could transmit signals via left hand relay 3G in a manner as described on the opposite side of apparatus.

It may be noted that the armature of either relay 36 repeats direct on to main line when either manual switch 40 is open. lVhen both switches 40 are closed the signals on lines 4 and 3 do not pass to lines 2 and l nor vice versa; line 4 is simply in communication with line 3 direct, and line 2 in communication with line l. Both Sounders locally then become audible.

To work independently, any line may be earthed at the segment ot its three-way plug switch by inserting an extra plug to join earth at 32, 33 34 or 35. Any line so earthed is not affected by signals from other lines, nor the signals of the repeating apparatus locally.

@ne line may be substituted for another and as the line Vwires and apparatus wires are shown atixed to switch board in Fig. 2 the method of substitution is as follows For clearness, call the upper part of the Vswitch board where numerals l, 2, 3, 4, ap-

pear North, the lower part of switch board South; the right hand East, the left hand lVest. To transpose or exchange the places ot' lines l and 3 by way of example the screw plug on bar connected to line l would be removed to two holes farther North, and the screw plug on bar connected to line 3 would be removed to two holes farther South. To exchange line wires the movement is either North or South in direction.

It will be seen that local circuits at 5l and 47 are broken. This is because they are not required when relays are to repeat direct on to main lines. Batteries 50 are therefore dormant. Plugs being out at 41, admit the local sounder batteries 42 to work Sounders 43 as previously explained.

Fig. 3: It will be observed that this tigure is, as hereinbefore stated, a simplification of the figure 2 and its working parts, as will be readily understood. Tt shows clearly how the relay armature repeats direct on to main line with plugs out ot the body of Fig. 2 and is meant, as hereinbetore stated i for the purpose of more clearly understanding Fig. 2. An attendant locally is required to arrange the manual switches 40 to suit requirements of distant stations. To the segment of four-way plug switch 2T at 23, 24, 25, 26 line wires are attached, which line wires are earthed at four distant stations. Assuming a distant'station on line 3 opened a key thereby breaking circuit, the right and lett hand relay armature contact points 3T would be open as shown. On closing`*such key a current would pass via, 23, right hand galvanometer 39, through the closed right hand manual switch 40 and relay 36, right hand key 33 to 2G, line 4 and earth at distant station. The result would be that magnet of right hand relay 36 would attract its armature to its contact point 3T which armature completes the circuit on the lines 2, 3. The armature.alluded to performs the otiice of key at the right hand Contact point 37. A current would pass from line l via. 24, lett hand relay 3G, right hand contact point 3T, right hand battery 42, magnet of right hand sounder 43, left hand galvanometer 39 and keys 3S to 25, and thus to distant stations on line 2.

It will be noticed right hand switch 40 is closed. This forms a local circuit whose sounder 43 and battery 42 are coniined each time a current operates on the magnet of right hand relay 3G closing such local circuit, and the lett hand sounder 43 is audible at each impulse of: current. hould such lefthand sounder cease to record signals, the attendant locally would close lett hand manual switch 40, and open right hand manual switch 40, to allow any station on lines l and 2 to communicate signals as already described on the opposite side of apparatus. The right hand galvanometer 39 is simply to show the strength of current on lines 3 and 4. The left hand galvanometer 39 is simply to show the strength of current on lines l and 2.

Fig. 4: This ligure constitutes an automatic repeater for four ways, without an attendant locally; certain plugs are inserted and others withdrawn from apparatus to form certain local circuits as will be hereinafter explained. Telegraph lines, carthed at distant stations, are joined to terminals ot switch board and are marked l, 3, 4. lf any key be opened on line 4 no current would be passing on main lines, and the apparatus would stand as shown in the drawing. The Contact pointl 37 of the armature of right hand relay 3G is open as also is contact point 3T of the armature of left hand relay 36. The right hand repeating transmitter 4G at its armature cont-act point 45 is open, but the left hand repeating transmitter 4G at its armature contact point 45 is closed.

Assuming now the distant key on line 4 be closed, a current passes from line 4, to bar ot switch board in lower series connected thereto; through screw plug` marked at 1T, along bar of upper series and line connected thereto to section of four way plug switch at 23, via three way plug switch 30 to lett hand manual switch 40, right hand galvanometer 39 (which shows the current),right hand key 33, magnet of right hand relayy 36, left hand repeating transmitter contact 45, three way pluO` switch 29 to 25 through segment of fourway switch 27 along line or wire to bar of upper series through screw plug 17 in switch board to bar of lower series connected to line 3 to distant stations. This shows that lines 4 and 3 are in direct communication. It may be mentioned, when all keys are closed in every lines stations, the armature of relays 36 make Contact at 37, so also armatures of repeating transmitters are closed at 45, locally. The eiifect of the key on line 4 being closed causes the magnet of the right hand relay 36 to attract the armature to its Contact point 37 which causes a closed local circuit via right hand local battery 50, magnet of right hand repeating transmitter 46, plug at 51, back to 37. The magnet attracts the armature of right hand repeating transmitter to contact point 45, which forms a signal on lines 2 and 1, so that all four lines get the signal. It has been explained that lines 4 and 3 are in direct communication, but the lines 2 and 1 get their signals by the right hand contact point 37 which acts and performs functions of a key operating the magnet of right hand repeating transmitter 46. The armature of riOht hand repeating transmitter lls the oce of key on the lines 2 and 1. The several armatures are detracted by springs which are adjusted to suit the respective currents main or loca-l. The right hand battery 50 gives a stronger iniiuence in the upper local circuit, when the armature of right hand relay contacts at right hand contact point 37. It then embraces the one magnet of right hand repeating transmitter 46 and consequently has a stronger influence than when the right hand contact point 37 is broken. The same battery then embraces the right hand magnet of local relay 43. Now assume the distant key on line 4 is again opened, the armature of right hand relay 36 leaves its contact point 37 when the right hand battery 50 operates on magnet of right hand relay 4S which attracts its armature to. contact point 49. This closes a. local circuit, without a battery, which bridges magnet of lett hand relay 43 rendering it inoperative. The lett hand battery 50 in consequence retains its strong influence on magnet of left hand repeat-ing transmitter 46 which holds its armature firmly on its contact point 45. A course is thus provided by wire clear through the apparatus to allow the said key on line 4 to make the next signal. Assume for clearness, that the magnet of right hand relay 36 is on the eastern side otl the apparatus, and the magnet of left hand relay 36 on the western side of apparatus. `When the eastern side or lines afecting the eastern side are signaling the following is the result-*An opening at right hand contact point 37 causes an opening at right hand Contact point 45, and a closing at right hand contact point 49. A closing at 37 causes a closing at 45, and an opening at 49. An opening and closing of any key affecting the eastern side make suclretfects at every moment. Signals are recorded from the eastern side to the western side at the right hand repeating transmitter armature contact point 45 which takes the function of a key. The western side, being constructed similarly to the eastern side, is capable of similar actions to those described.

Besides the plugs inserted in the three way plug switches 23, 29, 30, 31 to connect lines to apparatus, it will be observed that there are three other plugs inserted at 51, 41, 47, on each side of apparatus to form local circuits. As batteries and Sounders embraced by plugs 41 are not needed in the automatic arrangement shown in this figure their respective local circuits are bridged and inoperative. An extra plug at segments of three way plug switches 23, 29, 30, 31 which lead to earth at 32, 33, 34, 35, would earth the lines attached to such three way plug' switches so that one or all lines could be debarred from the influence of the repeating apparatus. 1n this arrangement of Fig. 4 the manual switches 40 remain closed. rPhe right hand galvanometer 39 shows the eurrent on lines operating the right hand relay. The left -hand galvanometer 39Ashows the current on the lines operating the left hand relay. The right hand key 38 operates the right hand relay and the lines attached thereto. The le-t hand key 38 operates the lett hand relay and the lines attached thereto. With all plugs out at 28, 29, 30 31, the apparatus in Fig. 4 is totally disconnected from main lines. Now by inserting a plug to join any two sections of four way plug switch 27 the lines so connected could work direct with each other. Assuming the top end marked 1, 2, 3, 4 of switch board is north; and the lower, opposite end, south; by moving screw plugs north or south one line may be made to substitute another line in a manner similar to that described for Fig. 2. The arrangement shown in Fig. 4 is purely automatic and requires no attendant.

Fig. 5: The apparatus shown in this figure operates exactly as described in Fig. 4 and is meant for the purpose of more clearly illustrating that ligure. This Fig. 5 therefore occupies the same relationship to Fig. 4 as Fig. 3 does to Fig. 2, and should be read with the description already given.

Fig. 6: It will be seen that in this figure the numerals 1, 2, 3, 4, 5, 6, 7, 8 indicate eight Morse telegraph lines. Line relays having the usual magnets and armatures CII essaie with spring retraction are marked 36 and the relay armature contact points are marked 37. Transmitting keys with circuit closing switches attached are shown at 33. Local batteries are marked 42. Galvanometers are marked 39. Sounders are marked 43. Plug` holes to contine Sounders are marked 41. Plug spaces to connect a pair of bars are marked 1G. The turning portions 17 of screw plugs show where a bar of the upper and a bar of the lower series are connected. Three way plug switches are marked The points of communication of lines with said switches are marked 23 and 24, and lines may be earthed locally at 32, 33, 34

Ain attendant is required only to alter the position oit the plug marked 22 to north or south on the switch board (that is assuming the upper part where lines are attached to switch board is north and the lower opposite end south) to suit the station on any line wishingl to signal the other.

As shown by the drawing with screw plugs connecting upper and lower series of bars of switch board at 17, and one plug 22 the apparatus is in position t'or any station on lines l or 2 to signal to lines 3, 4, 5, 6, 7 3, which are earthed at distant stations. Assume that line 1 desires to transmit signals. As Fig. (5 is shown all keys on the lines are closed. A current passing trom line 1 enters locally the segment ot its three way plug switch 55 at 24 thence to bar ot lower series connected thereto through screw plug vand from 17 along t-he connected bar of upper series to plug at 22 back along adjacent bar joined at 22 to next screw plug marked at 17 passing through same to bar ot lower series to galvanometer 39, magnet of relay 36, to segment ot' the same three way plug switch 55, but at point marked 23, to earth at distant stations on line 2. Thus lines 1 and 2 are in direct communication with each other.

The main current as traced creates magnetism in magnet of relay 36 which attracts its armature to Contact point 37 and such contact at 37 acts like a key on the next lines 3 and 4. Now to trace current on lines 3 and 4, start at segment of the three way plug switch 55 where line 3 is joined and marked 24, thence to connected bar of lower series to screw plug marked at 17 through screw plug and connected bar of upper series, along wire to local battery 42, to Contact point 37, along wire or line to magnet of sounder 43 along connected bar ot' upper series to screw plug through same and along connected bar of lower series to galvanometer 39, magnet of relay 3G, to point marked 23 and then to distant stations on line 4. Lines 5 and G may be traced by similar letters and figures. Lines 7 and 3 may be traced by similar letters and ligures. Now assume that a station on line 1 opens a key, such key breaks the circuit on line 1, the magnet of relay 36 on line 2 loses its magnetic power, consequently the armature loses contact at 3T which breaks lines 3 and 4. Lilies 3 and 4 having lost current the magnet of relay 3G on line 4 loses magnetism and its armature 37 breaks circuit on lines and G. The lines 5 and 6 having lost current the magnet of relay 3G on line G loses magnetism and lines 7 and 8 are broken at 37. Thus the 3 lines are void of current.

It will be seen that when a key breaks circuit all relay armatures, which act as keys for other lines, ily open in response to their respective armature springs and no current Hows on any line. Then the key is closed on line 1 a current flows and all relay armatures are attracted to contact points marked 37. In Fig. G all armatures of relays are closed at 37 and it will be observed that the armature at line 8 closes a local circuit via plug 22 on the right hand side of switch board. Trace the local circuit starting at armature contact point 37 of line S via local battery 42, along wire to screw plug marked at 17, still along bar of upper series to plug 22, back along the top or uppermost bar, via screw plug marked at 17 to magnet of sounder 43 to 37 the starting point. rlhe magnet of sounder 43 embraced in such local circuit is the only one confined in a local circuit and its armature acts with every impulse of current and is audible locally. It while the key on line 1 be forming signals a key on another line breaks a circuit the sounder described as being confined ceases to sound.

Any individual line may be earthed by inserting a plug in its respective three way plug switch or commutator 55, so as to allow it to work independently ot' the other lines. rlhe screw plug on the switch board may be moved to north or south to vsubstitute other lines in substantially the same manner as hereinbetore described; or the said screw plugs may be moved right or lett to other crossings or points ot' intersection to form various combinations. The keys 33 are for use of the local attendant.

That I claim is:

1. ln a telegraph system, a main circuit., a key and a principal relay therein, a second circuit, a repeater and a battery therein, a third circuit controlled by the repeater, a local relay in the second circuit, a circuit controlled by the armature of such local relay, a contact cont-rolled by the relay irst mentioned, and means for permitting current from said battery to operate the re` peater when sa'id contact is closed, suoli clos` ing operation simultaneously short-circuiting the local relay.

2.111 a telegraph system, a main circuit, a key and a principal relay therein, a second circuit, a repeater and a battery therein, a

third circuit controlled by the repeater, a local relay in the second circuit, a circuit controlled by the armature ot' such local relay, a second local relay connected with the circuit last mentioned, a contact controlled by the armature of the relay iirst mentioned, means permitting current from said battery to operate the repeater when said contact is closed, such closing operation simultaneously short-circuiting the local relay previously in circuit with the battery mentioned, said means permitting the last mentioned local relay when such contact is open to bridge the second local relay.

3. In a telegraph system, a switch com` prising several divisions, a main circuit connected with two of such divisions, a key and principal relay in said circuit, a second circuit, a repeater and a battery therein, a third circuit controlled by the repeater, a local relay in the second circuit, a circuit controlled by the armature ot' such local relay, a contact controlled by the relay iirstmentioned, and means permitting current from said battery to operate the repeater when said contact is closed, such closing operation simultaneously short-circuiting the local relay.

l. In a telegraph system, a switch com` prising several divisions, a main circuit connected with two otl such divisions, a key and a principal relay in such circuit, a second circuit, a repeater and a battery therein, a third circuit controlled by the repeater, a local relay in the second circuit, a circuit controlled by the armature of such local relay, a second local relay connected with the circuit last mentioned, a contact controlled by the arma ture of the relay first mentioned, means permitting current from said battery to operate the repeater when said contact is closed, such closing operation simultaneously short-circuiting the local relay previously in circuit with the battery, said means permitting the last mentioned relay when such contact is open to bridge the second local relay.

5. In a telegraph system, a plurality of main circuits, a key and a principal relay in each of said circuits, a plurality of associated circuits, a repeater and a battery in each of said associated circuits, said repeater controlled by their corresponding principal relays, the armature contacts of each of such repeaters when closed permitting of the operation of the principal relay in a main circuit other than the one from which the repeater receives current, and independent means connected with each oi the associated l I l l l circuits for' causing the operation of the re-I peater of the main ,circuit last-mentioned when the armature contacts of the repeaterv in the corresponding main circuit are open.

6. In a telegraph system, a plurality of main circuits, a key and a principal relay in each of said circuits, a plurality of associated circuits, armaturecontacts for each of the principal relays, such contacts having connect-ions across each of said associated circuits, a repeater and a battery in each of said associated circuits, a local relay in each of the circuits last mentioned, armature contacts for each local relay arranged to complete a circuit through the magnets of one of the repeaters, the magnets of each ot' the local relays being connected across the circuit completed by the contacts of the other local relay, means permitting current from one of the batteries to operate one of the repeaters when the armature contacts of one of said principal relays are closed, such means operating to permit the local relay in circuit with the battery last mentioned to bridge its corresponding local relay when such principal relay contacts are open, whereby the magnet of the other repeater receives a maximum current.

T. The combination with a switch board, comprising a plurality ot series of bars, ot a series of telegraph'circuits connected with the ends ot the bars, differential polar relays, repeating transmitters, transmitting keys, batteries, diiierential repeating sounders connected with such circuits, and means for causing any one of the circuits to repeat on any of the other circuits.

8. In a multiplex telegraph, a switchboard comprising a plurality of series of bars, switches connected with the bars, transmitting keys connected with said switches, relays connected with the transmitting keys, galvanometers connected with the relays, local sounders connected with the relays, a duplex telegraphic circuit comprising a comw plete set of telegraphic instruments and including a differential polar relay, a difierential neutralrelay connected with the switchboard, and means for causing any one of the relays to repeat onto any one ot the other relays or onto the duplex circuit.V

In testimony whereof I atliX my signature in the presence of two witnesses.

IVILLIAM LEIVE SLEY.

Titnesses REEs RUTLAND JONES, FREDERICK CRAWFORD.

Images