US969527A - Printing-telegraph. - Google Patents

Description

A. C. GREHORE.

PRINTING TELEGRAPH. vN DPLIGMION FILED AUG. 15, 1904.

Patented sept. 6, 1910.

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A. c. GRBHORE.

PRINTING TELBGRAPH,

APPLoATIoN FILED AUG'. 15, 1904. 4 969,527 t Patented Sept. 6, 1910.

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A. 0. GRBHORE.

PRINTING TELEGRAPH.

APPLICATION FILED AUG.15, 1904.

65,5%@ Patented Sept. 6, 1910.

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ALBERT C. CREHORE, OF YONKERS, NEW YORK, ASSIGNOR TO TYPEWRITING TEILE- GRAPH COMPANY, 0F NEW' YORK, N. Y., A CORIORATIQN OF NEW YORK.

PRINTING-TELEGRAPH.

Application tiled August 15, 196%.

Speeication of Letters Eatent.

.rar-.eaten sept. e, 191e.. Serial No. 220,711. l

o all whom it 'may concern.'

lle it known that. I, Animar G. Camions, a citizen ot' the United States, residing at Yonkers, county of lVestehester, State of New York, have invented certain new and useful Improvements in Printing-Telegraphs; and in pursuanceiot the statute I have set forth in the accompanying duwing and specification, as an illustration o't' the invention, that forni thereot4 which I now regard as the best one ot the various forms in which the principle ot' the invention may be embodied.

In the drawings, Figure 't is a diagram of the receiving relays. Fig. 2 is a circuit diagram oi the printing magnets. Figs. 3 and l are circuit diagrams of 'the transmit-ting devices, and Fig. 5 shows mode of locking the shift-magnets. Fig. G is al diagram of both lines with both transmitting and receiving apparatus.

My invention relates to a system ot telegraphy in which the principal object is first, to transmit messages by means ot a keyboard arranged like the keyboard of an ordinary typewriter-each button operating a circuit-closer and second, to receive the messages in a corresponding manner on a similar typewriter, the keys being operated by electromagnets. I accordingly do not undertake, in my prisent disclosure, to show the details ot the transmitting keyboard, but simply indicate a series ot circuit elosers which may, in ways well known to the art, be arrang d with a button for each of the circuit-closers. Likewise at the receiving station I do not undertake. to show `thedetails of the receiving typewriter, but simply show a series of magnets which will, in any desired manner, operate respectively the several key levers of a typewriter, including the' key levers corresponding to the severalletters and characters and, in addition, suitable shift-keys for capitals and figures and a key for returning the. carriage atthe 'end of Athe line. typewriters are already known and my re ceiving magnets may be applied to any spe cial form thereof in any desired manner.

By the use of the shift-keysI am able to transmit as many as ninety diterent characters` using three cases of thirty each, with two shift keys.

In my system it is possible to transmit two messages, one in each direction, duplexl in keyboard forni` Such' ing the lines by the well known method; but it requires 4two line wires to transmit a single message. 'I'

My invention utilizes as its basis the plan ot employing' two line wires operated independently of each other, with a. ground rd turn for each. Each wire is employedto select and operate some one ot' six secondary relays, there being twelve such relays in all, six tor each line wire, and the selection loeing made on each line by three .currents :of (litter-ent strengths, each working in two directions. No two ot the set of six secondary relays operated over one wire canbe operi ated simultaneously, but any one of them may be selected and operated by the' transmitting operator. Since the two line wires are independent, any oneyse'condary relayv of the set ot' six belonging to lone line n aayy be operated simultaneously',with `any one of the six belonging to the other line, and by operating a. single secondary relay only on each ot the twolines there are GXISGdiferent combinations ot the 12 secondaryrelays which may be made. Each of these 36 combinations is utilized to control an indilv idual magnet, and it will thus be evident thathsince it requires a single operation Cil only, over each line wire, to operate a print? ing-magnet, we have a system in which a single current. impulse only, over each wire, is required for each character transmitted. It thus appears that for a series of receiving magnets thirty-six in number, there is provided, for the control of each magnet,

. but 'twelve relays in all, and the relays are thus less in number than the receiving magnets controlled thereby. Moreover, out of the group of twelve relays a specified portion thereof, which I term a fractional group, act in the selection of any individual rece ng magnet. Inv addition the fractional groups corresponding to the respecti'revreeeiving magnets contain each the same number or relays. For example, out of the entire group ot twelve relays eaebtractional group will contain two relays and there are available in all thirtyhsix fractional groups,

containing two relaysand each corresponding to one' of the'thirtysix` receiving magnets. This same general principle may be employed witlrlarger fractional groups.

provided in each case all of thefractionalv groups contain the sameil number-ot relays.

sive where they are numbered trom l to 6` inclusive in Fig. l which illustrates the line A. K1, K2,-K are six dilerentially wound polar relays connected in series (they may be if desired in parallel or series parallel) one' half of the windings Ibeing in the line side and the other in the artificial line side, each half being connected vto groundA through the apex X. -Each relay armature is held by a spring (or by its magnetic bias) against its back stop when no currentliows vover the line, which is the normal position when not working. Three of the six relays, viz: K1, K2 and K3 are connected.v

in the proper sense so that a large positive current comingin .from line to ground will operate each of theml moving the three tongues over'to the respective front stops l, 1, l. -The other tlireb relays K4, K, K are'connected in the opposite sense so that a negative current going out from ground to line will operate them. "llie positive eurrent will then merely hold these three relay armatures K, 175, and K more firmly against' their back stops. In addition to this dierence in the sense of the relays, the relays K2 Y2 and K3Vv are wound and adjusted to respond. to different magnitudes of received current. To the smallest positive current, only relay Kv3 will respond; but to the next size of current both .l 2 and K2 will respond, while to the third size or largest current all three ot' the relays K1, K2 and K3 will respond.

lt will be noted that thev arnnitures of relays K1 and K2, K* and Ki", are provided with both front and back contacts while K and K have front contacts only, and that the back contact ot' 'K1 is connected with the.

intermediate set of secondary relays as. shown in liig. l, tor the customary purpose ot reinforcing the powei'ot the main. relays. rlhe iront contar-,t of the six relays, lil--l'i are respectively connected to six secondary .current operates secondary relay W2.

i-)peraling over line A.

relay magnets lit/l1, N2-lll and all the opposite terminals oit' these secondary relays connected to local battery l. rl`he levers of relays K1 and l* are connected to the op@ posite terminal of battery l2. By this dis-4 position of the local circuits it is seen that' if a small positive current is received over the line moving the armature of l alone to its front stop, there is a local circuit 'established from front stop l oli' li* to lever of Y2, to front. stop Zot K2,. to secondary-.relay "2 and thence tobattery. This rlhe circuit of secondary relay W3 isnow open 90 however and inoperative even -though its relay armature K3 1s against its iront stop Z.

YThe circuit from secondary relay ll passing through the front stop l and lever of K is open at. the back stop of lf2 whose lever is now against its front stop Z. Similarly, ify a large positive current is received operating all three 'of 'the relays lil, K2 and l@ simultaneously, the secondary relay lVl Iis the only one which will respond; for the circuits ol'fllv2 and W are open at the back stops of .K1 and li2; and the circuit of lll is closed. llence we may select any one olf the three secoinh'xnv relays N1 `W2 lVS by sending over thclinc a. large, intermediate, or small positive current; and similarly we may select anyY one of the three secondary relays XW, W1", lV by sending over the line a large, intermediate, or small' negativecurrent. A single impulse sent over the wire suliices to select and operate any one of the sixsecondary relays over one line wire 'By duplicating the ap aratus shown in l*1 ig. l a second group o secondary relays which may be referred to as l' TT-llm may may be referred to las line ll and which 'is illustrated in Fig. 6..

Fig. 2 illustrates one method of selecting any one of a group of 36 magnets by. means of the contacts controlled by the twelvesec-` ondary relays. ilhe several printing magnets are numbered and also marked .by the combination of the` two secondary relays which control them respectively. Thus the first print-ing magnet. 12-1, printing, say letter l), will lie controlled'by the secondary relays W12 operating over` line ll, and lV,

lays W1-JV, lope 'ating on line A, cach have los 115. `be operated over a second line wire, which rlhe secondary icand back ULL-71") contacts.

six independent contacts, and relays W7- `W12, operating on line B, each require a single contact only. It is evident from the diagram that the only path for current to "pass from the battery J when IV and IVl are closed is through magnet ,l2-1; for the magnets T-SG can receive no current, since their circuits are open atthe contacts V7-JW leading to the respective magnet groups 7a, 8, 9, 10a, and 11a. The magnets Q-G receive no current, since one terminal of each is open at contacts of the secondary relays 1V?, 1V, 1W, 75, and 1W. `In a similar manner any other one of the BG printing magnets might be selected, by 'closing the proper pair of secondary relays, one from the group Vfl to W and the other from the group VVT-IV.

It remains to be explained how some one 'of ditt'erent kinds of current can be trans- -initted simultaneously over each line wire in order to select one of the thirty-six printing magnets the required currents being the thi'ee values of positive current and the three values of ijiegative current.

Referring to Fig. 25, S and S2 represent two grounded batteries-or one large battery grouiided at its middle {mint-eso that one battery S, willv send positive current and the other negative current to line. Dl-D represent six separate circuit closers having 'qb-g with both iront (Zik-7M) The levers are held by springs in contact with the back contacts U-/if which is the normal position. Then in this position there is a completed circuit from line to `ground through the back contacts ot the sii: circuit closers in series and through the. resistance R which is inserted so as not to disturb the balance in duplex working. This circuit is from line A to lever qu of circuit closer 1), to back contact i. and thence to lever gt; back contactr, lever y* etc., until ive-reach resistance R and yround E. The normal condition is thereiore line grounded and batteries open. Now let lever g1 be operated and move from its back stop 71.1 to its front stop k1. The path through resistance R from line to ground is thus opened at h1, and the circuit is now completed from line through the back contacts of the tive circuit closcrs IDL-D as before, and thence to/ir1 and protective resistance R1, to a and through the whole Elositive battery S1 to ground E. In a simir manner if the lever g2 of circuit closer -D2 -is the'only one of the six to be operated,

i circuit a2 through ay portion'of positive batl lsmallest Apositive current to line. D4 sends tory Sl and ground E. In a similar manner lever g3 of circuit f closer I)3 sends the the largest negative current and D5, the int-erinediate negative current, and Da the-r smallest negative current. By supplying-for v the duplicate arrangement on line B, six other circuit closers D7-D12 and connecting theni to the saine `l'iatteries S1 andS2 ot F ig. 3 in a niannerprecisely similar to the diagram of Fig. 3 the second rline wire B may be made to receive in like manner any one of six kinds oi' current for operating the set ot six secondary relays I TT-w as already de,- scribed. These circuit closers I)-D2 niight be operated by hand, in which case it would be necessary for the operator to learn which coniliiinations correspond to particular characters. A better plan is to provide twelve electromagnets one to control each circuit closer and operate these electromagnets from 'a keyboard. In Fig. al. I have shown such an arrangement-` In this drawing P clz represent the coils of twelve magnets which control respectively the twelve circuit closersr l1 and (i12 in series whenever the key 1412 is closed. Moreover the only path established for current by closing 1 12 is through magnets (Z1 and lll?, all of the other magnets Z2- dll remaining on open circuit,`

as an inspection of the diagram makes evident. rFliese thirty-six circuit closers may be arranged in the forni of a keyboard con-A venient for an operator; or they may be atf tached to the keys of a typewriter similar to the receiving typewriter, so that the transmitting operator sees the record printed on the home transmitting typewriter and makes an exact duplicate of that. made by the re-V ceiving typewriter.

If a keyboard only-is provided instead of a transmitting typewriter, there is an additional requirement to provide means of warning the operator of the approach of the receiving typewriter tothe end of the line when thecarriage must be` returned. This may easily be arranged by providing a counter attachment to the transmitting keyboard i which will ring a bell or give suitable warn-` say the letter S, from'the time the transmitting operator transmits it, until it is received and the apparatus restored into condi* tion to receive the next letter. the key l-ll Fig. l corresponds tcthe letter S. rilhe operator depresses this key and simultaneously operates the two transmitters D1 and 311. The lever g1 (F ig. 3)

moves into contact with front stop k1 and leaves the back stop itl. This operation puts the largest positive current from battery S1 on the line In a similar manner transmitter D (corresponding to D for line A.) moves its lever to its front stop and puts an intermediate negative current from battery S2 on line B (not shown in the drawings). The current on line A operates the three relays K1, K2,and K3 moving the armatures to the front stop Z, Fig. 1,'butholds' the armatures of Kt K5 and K more firmly against the back stops. rlhe only circuit established through the local battery P is through secondary relay TV1 all the other five remaining open. Similarly on line B relays K10 and K will be operated by the intermediate negative current (correspond` ing to K''and K5 on line A.) and the secondary relay )V11 will be the only one or" the set NLJi/t which is operated. Secondary relay W closes the single local contact (Fig. 2) connecting with wire leading to group lla including the set of six printing magnets 7-12, and, at the same time, secondary relay Vin closes the six contacts leading to six printing magnets (one in each of the several groups 7Bf-12) numbered l, 7, 13, 19, 25 and 31. The printing magnet No. 7

also marked with the combination ll-l is' the only one common to the two groups, and the only one vwhich `will be operated; and this magnet depresses the typewriter key thus printing the letter SA as would be the case it the operator depressed this same key with the finger. T he printing magnet 7 will remain excited as long as the transmitting operator continues to hold down the key (l-ll Fig. 4i). key, the various transmitter relays and secondary relays involved are immet-liatcly restored by their retractable springs, and the system 1s ready for the next character to be transmitted.

-way and remain se till released by the re- Suppose that As soon as he releases th s senaat' l leasing magnet. One mode is shown in Fig.

5, wherein the Cap shift-magnet F1, and the Fig shift-magnet F2 are each provided with a. retaining coil, f1 and f2 in the circuit ot battery P2, these coils being automatically energized whenever their respective magnets F1 or F2 act, and remaining en.

ergized until the circuit of battery P2 is broken by release magnet It will be evident that in the use o't three different current values, any large leakage on the line will tend to cause trouble by reducing the current strength of a large value to the lower value of the next smaller current. This may be compensated .for by re adjusting the several relays to a lower power While still retaining the same ratio of power between them, or it may be compensated for by increasing the electric pressure I prefer however,

at the sending station. to shunt the receiving relays by an adjustable resistance Z, Fig. l, so that an adjustable portion of the current will pass through the shunt and by increasing or decreasing its resistance a larger or smaller portion ot the current may be diverted into the relays. t

lt is to be understood that my invention may be embodied in various specific forms by one familiar with the art.

ln l? ig. 6, I have shown an assemblage diagram of the apparatus on both lines which will be readily understood from the description already given. I will alsoadd that while it is much preferable to employ the secondary relays, yet it is only the l2 main line relays whichare relied upon for selecting and, if desired, operating the individual magnets to be operated. By combiuingthese 12 relays in groups of two, (on my general principle of combining a given number of' rela-'ys in fractional groups, each group containing the same number of re-V lays,) l am enabled to utilize the entire selective capacity of the relays in a simple manner. By means of this principle I can secure a maximum number of combinations with a minimum number of relays. From another point of view it may be said thatthe number of relays in each set is equal to the square root of the number of receiving magnets controlled thereby. Thus, each ot' the six relaysin one set combines with first one and then 4another ot' the relays in the other set, until it has coperated in turn with each ot the six, making a seleption of some one receiving magnet at each coperation. Each of the six in one set thus cooperating in turn with cach of the six in the other set give .is six times six, or 3G selections. The same is true of the relation between the 12' relays and the 3G transmitting keys at the sending station. .'Each key, by controlling two contacts, selects two relays at the receiving station, one` from each set and there being, as described, 36 possible combinations of t-be l2 relays in groups of two, there will be 3.6 keys, the'number ot keys being equal to thesquare of. the numr ber of relays in each relay set.

That I claim as new and desire to secure 'fractional groups coxitaining the naar ber of relays, and means for simultaneously energizing trom a distant station the relays contained in any vone of the said fractional groups. Y

Q. In a telegraph system, the combination with a series ot" receiving magnets, of a series of controlling relays therefor less in number than the said magnets, each magnet being controlled by a fractional group of the said relays independently 'of the controlling contacts of the remaining relays and each of the said fractional groups containing the same number of relays, together with two line wires and means for simultaneously energizing trom a. distant station the relays lcomposing any one ot said fractional groups a part otl the component relays ol each tractional group being energized over one line wire and another part over the second line wire.

ln a telegraph system, the con'ibination with a series of 'receivingfmagnetg of a series ot controlling relays therefor less in number than the said n'rignets, each of the said magnets being controlled by a 'tractional group ot said relaysindependently of the controlling contacts ot the remaining relays and each fractional group containing the same number of relays, two line wires` each containing a portion ot said relays and vmeans for energizing the relays trom a dis tant station by currents ot a ditferent and distinctivevalue. transmitted over each ol; said line wires,

4.2111 a telegraph system, the combinationrate line circuits, a local circuit for cach of said magnets and two circuit closers in series in each ot said local circuits, the said circuit closers controlling the said circuits and operated respectively by two relays one from each of the two sets aforesaid.

(l. ln a telegral'ih system, the combination with a series et' receiving magnets, of two sets ot' relays included respectively in separate lines and operated by distinctive circuits,a local circuit tor each of said magnets, and two circuit closers in series in each of the said local circuits, the said circuitv closers controlling the local circuit in which they are contained and being operatedA respectively by two relays one from each cf the two sets aforesaid. v

7. lin a telegraph system, the combination with a series ot receiving magnets of local circuits t'or said magnets respectively, each local circuit containing and controlled by two circuit closers in series, and a series of relays in number than the said magnets operated by distinctive currents and each group ot two of the said relays cont-rolling respectively the said circuit closers in one of the several local circuits of the receiving magnets independently of the controlling contacts ot the remaining relays. i

ln a telegraph system, the combination with two line wires,"of 'a series of relays 'contained in lach line wire and responding to currents ot distinctive value, local circuits control-led by each oiE the said relays, the local circuit controlled by a weaker relay being also controlled by a more powerful relay, and a series ot receiving magnets, each having a local circuit controlled by two relays, one'in each ot the said series.

9. ln a telegraph system, the combination with a series of magnets divided into groups, ot a series ot controlling relays therefor less in number than the magnets, and circuit closers operated thereby, cach magnet being controlled by a fractional group ot the said .relays indepeiulently of the controlling con- `tacts ot the remaining relays and each of the respective fraction-al groups containing two relays, one oi' the two controlling al group ot said receivingy magnets and the other controlling one of the individual magnets in said group.

lO. In atelegraph system, the combina-y ico iso

erated by distinctive currentsof a series of local circuits, each containing a receiving magnet controlled by V.t\vo circuit closers in series operated respectively by two relays one from each of the aforesaid tivo sets, the circuit controlled by a ivealier relay being also controlled by amore powerful relay.

l2. ln a telegraph system, the combination ot a 'series ot' receiving magnets, a series ot relays less in number than the magnets and divided into groups of two, each group controlling one ot the said series ot-magnets, means for operating the said magnets by currents of' dilterent values,l and a shunt around the said relayscontaining an adjustableresistance.

13. ln a telegraph system, the combiniii tion with a series ot receiving magnets, -ot' controlling relays therefor ot'vvhicli a plurality included in the same line` circuit and of which the number is less than the. ninnber ot said magnets, each magnet being controlled by a group of tivo relays independently of the controlling contactl of the remaining relays, 'and a series olr transmitting circuit closets each controllii'ig' a pair of the said relays.

l-l-. l'n a teiegraphsystem, the combination with a series ot receiving magnets, ot a series et receiving relays responding` to distinctive currents, a'series ot local circuits for the respective magnets, tivo circuit closers in each et the said local circuits operated respectively by two of the said relays, and controlling one of the receiving magnets .inde Jendeu'tly of the controlling contacts ot' tlie remaining relays and a series of transmitting circuit elosers corresponding to the receiving magnets and each controlling a ditierent pair of said relays by currents of distinctive value and polarity.

l5. in a telegraph system, the combination with a series et receiving relays spending respectively to currents of ditierent value, of a line wire, and transmitting devices comprising a series of electric generators of ditlierent values, circuit-closer connecting each o said generators to the said line wire, and a ground connection for the line Wire at the transmitting station adapted to be. broken sutcmaticaily by thev operation of said circuit closer.

i6. in av telegraph system., the combination with a series of receiving relays responding respectively 'to cu. nts of diliiei'ent values, et a line wire containing said relays, a series oi.E generators, a. series of circuitclosei's corresponding to the said generators for connecting them to the said line Wire, and a ground connection for the line Wire passing 'through the said circuit closers in series, whereby the operation ofany one of the circuit closers will break: the sind ground connection.

cease? 17. In a telegraph system, the combina- .tion with a series of receiving relays recurrents of 'ditierent values, va normally open.

connection from each generator containing a resistance, a circuit'closcr for each generator 'for connecting it to the line Wire through its respective resistance, and a ground connection for the line wire containingv a. resistance 'and controlled by each of the said circuit closers.

18. In a telegraph system, the combination with a. series of receiving magnets, of local circuits therefor, a series of relays less in .number than the magnets, circuit closers in series in the local circuit ot each receivt'ractional group of the said relays, a locking device t'or one or more of theV said magnets, and a release for saidr locking device controlled by another of said magnets.l

19. In a telegraph system, the combination with a series ot' receiving magnets, ofa series of receiving relays less in number than the magnets, circuit closers in series in ing magnet simultaneously operated by, a

the circuit of each magnet,v and a retaining series of relays less in number 'than the receiving magnets and responding in -fractional groups to distinctive currents, circuit closers in the circuit of each magnet voperated simultaneously by each fractional group of relays, a line Wire, a series ot generators giving currents ot' dilferent value, a series oi' transmitting circuit closets, an operating magnet -or each circuit closer, and a series of transmitting keys each controlling 'afractional group of said voperating magnets.

2l. A telegraph system comprising the combination of two sets of six relays each, two line Wires each containing one of said sets, a plurality of receiving magnets. each havingits circuit controlled by two circuit eloses in series operated respectively by two relays one from each of the two sets aforesaid, andI means for selecting and operating' a relay from each set by a single current impulse on each line Wire transmitted simultaneously from a, sending station.`

22. A telegraph systeiiicomprising the combination of tWo line Wires, receiving relays in scrieson each line wire, means for operating any selected one ci the relays upon each line Wire independently of the remainingrelays, and a series of receiving escasa? magnets each controlled individually by a predetermined pair of`^--relays so selected.

23. A. telegraph system comprising the combination of a series of selectingrelays of Which a plurality are included in the same line circuit, a series of receiving magnets greater in number than the said relays, each magnet being controlled by a fractional group of said selecting relays and each fractional group containing the same number of relays, together with means for energizing from a distant station the relays composing any one of said fractional groups.

2a. A telegraph system comprising in combination main line relays, a plurality of receiving magnets greater in number than the said relays and connected in groups' equal in number to one half the number of said relays, the groups being in multiple are with one another and the individual' magnets being also in multiple are with'one another in eachgroup, circuit closers for the individual magnets respectively, circuit closers for the respective groups, two econdary relays, one operating a group circuit closer and the other operating a plurality of individual circuit closers one from each group, and means for energizing the secondary relays by the operation in the fractional group of said main line relays.

Q5. A telegraph system comprising the combination otl a plurality of receiving relays, a plurality of receiving magnets divided into groups, a local generator, a plurality of contacts connected in multiple to one terminal of the generator each contact being controlled by a relay and controlling a group of said receiving magnets, a plu- 'ality of wnta'ets connected in multiple to the opposite terminal each controlled by a relay and controlling a plurality of individual lreceiving magnets from different groupsVand means for selecting the said cfgtipllillg relays in pairs from a sending station. i

26. In a telcgrapli system', the combination with a local generator at a receiving station, of a plurality of contacts connected in multiple are to each generator terminal, the contacts on one side controlling groups of' receiving ma nets, while those on the other side contro each a plurality of individual receiviiw magnets from different groups, and 'relays operating in pairstq.i

close the contacts on opposite sides of said generator respectively.

27. In a telegraph system the combination with a set of transmitting keys each having a single pair of contacts, of two sets of Vmagnets at the receiving station, each set having magnets equal in number to the square root of the number of said keys, and means for selecting and operating a single one from each of said sets of magnets by the operation of one of said keys. y

28. In a 'telegraph 'system the combination with a set of thirty-six transmitting keys each having a single pair vof lcontacts, of two sets of magnets at the receiving station, each set consisting of six magnets, and means for selecting and operating a single one from each of said sets of magnets by the'operation of one of said keys.

29. In a telegraph system, the combination with a series of receiving magnets of two sets of relay magnets controlling the said receiving magnets, each set of relay magnets being equal in number to the square root of the number of receiving magnets, and means for selecting and operating one of the said receiving magnets by the operation of two relay magnets, one from each of the aforesaid two sets of relay magnets independently of the controlling contacts of the remaining relays.

30. In a telegraph system, the combination with thirty-six receiving magnets of two sets 'line relays, and recording mechanism controlled by said secondary relays.

In witness whereof I have hereunto set my hand before two subscribing witnesses,

this 10th day of August, 1904.

ALBERT C. CREHORE.

Witnesses:

e G. W. HOPKINS. w L; T. SHAW.

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