US1622A - Improvement in the electro-magnetic telegraph - Google Patents

Improvement in the electro-magnetic telegraph Download PDF


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US1622A US1622A US 1622 A US1622 A US 1622A US 1622 A US1622 A US 1622A
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Y 3 Sheets-Sheet 1. C. WHEATSTO'NE 8a W.' F. COOKE.


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Patented June 10 T mwyfmm) TH: Nomus PETERS co. HHQTQLITNQJWASHINQTON. n. c.


1\T0,.1`,'6.2Z.A v Y 'Patented June 10, 1842t Tu: Noams versus co.. PHoramo.. wnsunmwn4 D4 a sweets-sheen 3.. C. WHEAT STONE'& W. EUOQKE.4


No.1.622- Patented June1o,1a42.



Specification forming part of Letters Patent No. 1,1322, dated J'unelO, 1840'. y

To alta-hom it may concern We, CHARLES WHE'rs'roNE, of Conduit Street, Hanover Square, in the county of Middlesex, esqnire, and WILLIAM FoTHERGlLL COOKE, of Breeds Place, Hastings, in the county of Sussex, esqnire, severally send greeting:

Whereas we have discovered or invented certain new and useful improvements in giving signals and sounding alarms in distant places by means ot' electric currentsV transmitted through metallic circuits; and whereas we desire to obtain an exclusiveproperty incur said invention or discovery throughout the United States ot'America, and we are. therefore, about to make 'due 'application to the Commissioner of Patents in and for the said United States, expressing sucn our desire:

Now, therefore, know ye that, in compliance with all the laws and statutes ofthe said lUnited States, and more particularly ot an act passed on or about the 4th day ot' July, 1836, entitled. An act to promote the progress of useful arts, and to repeal all acts and parts Aof acts heretofore made for that purpose, we, the said CHARLES WHEATSTONE and WILLIAM Forn- ERGILL CooxE, do hereby and by the three sheets ot drawings hereunto annexed, fully,

pounding the same; and we do hereby and by the said sheets of drawings fully explain the principle of our said invention or discovery and the several modes in which we have contemplated the application ot' that principle or character by which our said invention or dis; covery may be distinguished from other inventions, and do particularly specify and point out the parts, improvements, or combinations which we claim as our own invention or discovery in the following mannerthatis to say: We shall first describe certain apparatus. or mechanism which is constructed according to our said improvements for giving signals and sounding alarms in distant places by means of electric currents transmitted through metallic circuits, and then at the conclusion of this our specification we shall point out the particular improvements whereof the exclusive use .is granted by the said Letters Patent.-

The description of the apparatus or mechanism will be 'facilitated by considering it as being composed of the following principal portions, which operate in concert for giving sig-l nalsorsoundingalarmsindistantplaces: One y of those portions is situated ata convenient f place (which may be called a terminus) and adapted for being operated upon by a person who intends giving signals or sounding alarms in distant places. Another portion (with du.-

another'in different distant places, all-:Which duplicates will operate simultaneously-that is,they will exhibitlike signalsor they may sound like alarms in all the several more and more distant places at the same time; but'the place Wh ere the most remote of all the said duf plicates is situated may be called 'the distant terminus.

And for communicating between the several portionsot' the apparatus which are situated, as aforesaid, at a distance one from another, a number of metallic rods or wires, which are suitably arranged and prepared for conducting electric currents throughout their lengths, are extended from the Erst-mentioned terminus and portion 'of the apparatus aforesaid to reach through all the other aforesaid more and more distant portions thereof to that portion which is at the distant terminus, the arrangement of the Saidconducting-wires being such that they form as many distinct lines of extension or courses capable of conducting electric currents from one terminnsto the other as there are wires, each wire being kept distinct or .insulated from all the other Wires; also, that in extending from the tirst-men tioned terminus and portion of the apparatus `to the'nearest duplicate of the distant portion and insulated from all the other wires, so as to Y be qua-lined for transmitting or conducting an electric current throughout its whole length from the rst-mentioned terminus and portion ofthe apparatus to the most distant'por tion thereof at the other terminus Without -interruption to the continuity ot' the said current in passing through as many duplicates of that most distantportion as maybe established at intermediate places between the two termini; but, note, it is not an essential part of the apparatus that there should be any such duplicates of the distant portion, for in cases where it is not 'required to give sign als or sound alarms at any intermediate places between the two termini, the first-mentioned portion of the apparatus'being situated at one terminus, as aforesaid, and the other distant p0r- 1 tion thereof beingsituated at the other terminus, .the several conducting-wires will extend from one terminus and portion to the other terminus and portion, the several wires being in all cases insulated and kept distinct one from another.

And, further, the first-mentioned portion ot' the apparatus, which is situated at one o't the termini, as aforesaid, should be provided with some such kind of electric apparatus as is usually termed a voltaic battery,`and which may jbe on any construction which is capable of exciting or producing electric currents through lmetallic circuits-thatis to say,it' one end of a great length of insulated conducting rod or wire of metal (forming a continuity of metal) lis broughtinto contact with one pole of such abatteryand the other end' of the samewire isbrought into contact with the other pole of the same battery, so that such rod or wire formswhat is termed a metallic circuit, then a continuous electric current will be transmitted throughout all the length of such wire or metallic circuit in consequence of a continual transmission of electric action, which, as soon as such a circuit is formed, begins to proceed from one pole of the battery and along or through all the length of the conducting-wire with a very `great velocity of transmission, in order to return to the other pole of the same batterythe electric current thereby performing a circuit from the battery and back again thereto; vand the said electric current or transmission of.

electric action in a circuit willf continue withont interruption or cessation so long as the metallic circuit is maintaiued-tha't is, so long as the aforesaid contacts of the two ends of the conductingwire with the two poles of the battery (and so long as the continuity of metal throughout the Whole length of that wire) is continued, provided that the battery is kept in working order-but note, by continuity of metal. in the couducting-wire, it is not meant that the whole length of such wire is necessarily made of one unbroken piece ofl metal, but merely that the ends of every separate piece of metal, whereof the whole length is.

composed, are efi'ectually connected together with suitable contacts for conducting electric currents.

And the person who intends giving signals or sounding alarms at a distance, can do so by application and pressure of his hands or ngers upon suitable buttons or finger-keys be-y longing to that first-mentioned portion of the Vbattery along one or more ofthe said particular wires to the distant portion of the apparatus at the other terminus, and thence back again through some other (or some others) of f the said particular wires to return tofthe other pole of the same voltaic battery, and 'thereby perform an electric circuit. The manner whereby such an electric current through a metallic circuit is caused 4to give signals or sound alarms in distant places will be hereinafter explained. The said electric current which is so transmitted through those particular wires which are thus formed into a metallic circuit passes, withoutinterrnptionto the continuity of the current, in makingits progress from the battery, through all the several duplicatesllof the distant portion of the apparatus, which may, as before explained, be situated at intermediate placesrbetween the two termini, or else the said current repasses, without interruption to the continuity ot' the current, in making its return toward the battery, through all the said duplicates; but in either case thev electric cur;ent is caused to produce alike and simultaneous effect, upon all the several dis-- tant portions of the apparatus-that is to say, whatever effect the electric current produces vupon 'the most remote portion ofthe apparatus, which is situated atthe distant terminus, it will alsoproduce a like and simultaneous effect upon all theseveralduplicates 0f that portion which may be situated at intermediate places between the two termini, and the said transmission of such an electric current will continue so long as the pressure is continued on the aforesaid buttons or finger-keys, but `no longer, because the metallic circuit is broken and mes .null the instant that .the said buttons or keys are released from pressure, and Ythat a cessation thereby takes place in those contacts and connections which had been for the time established, as aforesaid, between the two poles of the voltaic battery and certain of the conducting-wires, in order to form those particular wires into a metallic circuit for the transmission of an electric current through them, as aforesaid.

'And note, by applying pressure of the hand or fingers upon other suitable buttons or in ger-keys among divers such with which the said first-mentioned portion of the apparatus is provided, contacts and connections may be formed betweenv the aforesaid ends of the particular conducting-wires before mentioned and the contrary poles of the s aid voltaic battery to those poles thereof with. which the .same ends were before connected, wherefore, valthough the same metallic circuit will be formed among the several'conducting wires as before, nevertheless the transmission ofthe electric current will take place in a contrary direction through that metallic circuit, and such reversal of the direction of the transmission of the electric current through the samel metallic circuit is caused to produce corresponding differences in the appearance and signification of the signals which are given (in manner hereinai'ter described)in distant places by transmission of an electric current through the same metallic circuit.

And note, by pressure upon other suitable buttons or tin ger-keys among a diversity thereof, the ends of other of the conducting-Wires with which the apparatus is provided ymay be connected with the poles of the battery, so as to be formed in like manner, asalready described, into a metallic circuit, but which will be a dit'- fcrent circuit from that already described, because it will be formed by different' wires, and so,accordingtothenumberofconducting-wires with which the apparatus is providcd,'scveral different metallic circuits' may be formed, and the transmission of an electric current through -each of su'ch different metallic circuits as may be so formed (although excited bythe same battery) may be caused to give a different sig# nal in distant places, each of. which signals is susceptible of two different significations, according as the current is caused to yproceed through the particular metallic circuit in one direction or in the contrary direction.

And note, also, the apparatus or mechanism may be so arranged as that bypressure upon suitable of the said buttons.'4 or finger-keys two (or in some cases more) of the said difterent metallic circuits may be formed out of the several conducting-wires at the same timefor the contemporaneous transmission of two or more distinct electric currents which may beexcited by the lsame battery, and although each of such currents should only give one signal, (with one or otherof those two signiiieations which belong thereto, according to the direction in which the current acts,) nevertheless the combination or concurrent exhibition of two or more signals by means of as many distinct electric currents may have a different signitication to that signification which would appertain to the exhibition of -either of the signais by itself. But note, two concurrent sig' nals may be exhibited at the same time with out forming two distinct currents, aslast men-y tioned, but by the transmission ot' only'7 one electric current through one metallic circuit, because as each circuit is composed of two conductingwires-unlited for the time intoone. circuit, each wire may be considered 'as one halt' of that circuit,'andthe electric current in proceeding along ,one wireor halt of the cir cuit in a` direction from the battery toward the distantterminus may give one signal, and the same cnrrent'i'n' returning along the other wire orhalf ofthe circuit in-a direction t0- ward the batteryl (in orderto complete its eircuit) may give another signal, the simultaneons andA concurrent exhibition of which two signals may have a different signification from that which would appertain tothe exhibition of either ofthe signals by itself or to the concurrent exhibition of either ot' the'said signals with any other signal with which it might be brought into concurrence. But notwithstanding the two contemporaneous signals may'b'e thus exhibited in concurrence by transmission of only one'eleetric current through one metallic circuit which is composed of' two wires, nevertheless the two signals which are so brought into concurrence may be dittferently' paired, or their concurrence maybe diversified.

at the pleasure ot` the operator, because it' each;

distinct conducting-wire out ot', a number of such is adapted to produce its appropriate signal by transmission ot an electric current through that particular wire,.then by pressure of suitable butt'ons'or keys, as aforesaitl`,,ai.iy two of such wires may be conjoined into one metallic circuit, and theelectric current which is transmitted through that circuit will exhibit y'tw-o'concurrent signalait/nich may, at thepleasure of the operator, be the coucurrenceof yany twofof the whole number oi. individual signals-which the several wires are qualified to produceindividually.

And by virtueot' the several means above described the apparatus or mechanism may bearranged so as to be quali-tied to 'form (at the pleasure of the operator) 5a variety of dit'- i'erent metallic circuits, each such circuit being adapted to give its own-appropriate signal; but, nevertheless, the electric current which will be transmitted through each of those circuits can be made to give two dii'erent signications to the signal belonging to that circut,-a'ccording to the direction of the current 'or the apparatus or mechanism may be so arrangedas to be capable of forming two or more metallic circuits with a distinct electric current through each circuit at the saine time, .in order to exhibit two (orin some cases more) signals in concurrence; or the apparatus or mechanism may be arranged so as to be capa` Able ot giving two signals in, concurrence by the transmission ot an electric current through one metallic circuit, with capability ot' diversifying the concurrence' ot' the two signals which will be brought into concurrence by the formationof one metallic circuit; and hence, by one or other or all ot' those various means, a suicient diversity ot' signals and change in the significations of those signals can be given in distant places for constituting a telegraphic language or mode ot' communicating letters of the alphabet and numeral or symbolic characters.

And, furthermore, the manner. whereby the aforesaid transmission of electric currents through metallic circuits is caused .to give signals orto sound alarms in distant places is either by the angular motions which such currents are capable of giving to magnetic needles which are poised upon centers of mol,tion and placed in suitable proximity to the said conducting-wires throughwhich suchcuijrents are transmitted; or else by the attractive force of occasional magnetism which such cuf rents are capable of exciting in masses of iron which are not magnets themselves, but which' of the said modes ot action, combined 'in suchfV manner as is suitable for giving `such signals or sounding such alarms at a distance, as may be required. ,c

And respect-ing the adaptation of magnetic needles for giving signals the'same may be made like compass-needles, but fixed on axes passing through theircenters of motion, and those axes mounted delicately on pivots .at their ends in the manner of the arbors of Watchwheels, so as to render the needles capable of moving lvery freely with angular motion about their centers of motion. Each` needleV must have some slight tendency given to it to induce it topoint in one particular direction whenever it is left vto itself and uniniluenced hy the electrical current. The simplest,and perhaps the best, mode of giving such a tendency is by gravitation, in lwhichv case the axis of the nee. dle must be horizontal, or nearly so, and, one end otl the needle being madev rather heavier than the other, that heavy end of 'the needle will always point downward'when the needle is left to itself; 'and whenever the needle does so point upward and downward itdenotes that it is quiescent, or at rest, and that it is not giving' any signal. i

One of the comlueting-wires before mentioned is disposed vertically or in a direction parallel to the needle when the same is at rest,

4the wire being situate as near to the needle as can be to avoid touching, and when an electric current is transmitted, in manner already explained,through,the said wire so as to pass in proximity to the needle, that current will give the needle a slight tendency to move about its center with an angular motion .-or dellection from its previous parallelism to the -If the transmission oi' the current through the wire is in one direction the needle will acquire a slight tendency to deflectl one way from the saidparallelism, hutif the transmission is in the contrary direction the .tendency will he to deflect the other way. But note, as the tendency to deflection thus given to the needle is but slight, it requires to be multiplied by the same means as is resorted to for n like purpose in the instruments `well known by the name of galvanometersL-.that is, by causing the'conducting-wiretoform many convolutions around 'the needle or around a narrow space withinwhich the needle is left at liberty to move, -but without touching any of the convolutions that the wire makes, the order of the said convolutions of the wire being lsuch as that the wire shall always transmit the electric current in one direction at one side of the plaue'in which the needle-moves, but shall transmit the current in the contrary direction at the other side of that'plane.

`To produce such convolutions of the wire it must be coiled around the space in which the needle moves, all the ascending parts ot' the coils being at one side of the needle-that is,- toward one end of its axis-and all the descending parts of the coils being at the other side of the'needle, (or near to the other end of its axis.) With this arrangement of the conducting-wire each ascending as well as descending part of the several coils will transmitthe electric current in the proper direction for giving the needle a tendency to detlection' one way or other, according to the direction in which the current is transmitted through the lcoiled wire, and the concurrence of an adequate number of such coils may be made to multiply' the before-mentioned slight tendency ofthe needleto'deiiection until it becomes sufticientto turn the needle (notwithstanding the gravitation ot', its heavy end) with a sudden and decided ymotion to one v .side or other of its' quiescent or vertical position the instant that the transmission of an electric current through the wire is commenced by the formation of two ol" the conductingewires into a metallic circuit by pressure on suitable buttons or finger-keys as already mentioned.

T he extent of deflection or angular motion that the needle is permitted lto perform in consequence of thc tendency to deflection which it then acquires is limited byjflxed stops, and the instant thatby pressure on the said buttons a metallic circuit is formed, and an electric current beginsv to be transmitted through the coils' of wire, the needle moves suddenly from its ,quiescent or vertical position until it comes 'to-rest in anl inclined position against one of its said stops; and it will remain moi tionless in that inclined position so long as the current is continued; and when the needle is at rest in such an inclined position it will point to some character, letter, ligure, or symbol which is marked on asuitable dial or tablet, and it is by so causing a needle to point to such character, letter, figure, or symbolgthat-a signal is given. When the needleis thus made to in eline to vone side of its quiescent or verticalposition as far as itstop will allow, it will point to and signify one character, letter, ligure, or symbol on the dial or tablet; but when, by reversing the directio'nrof the electric current through the ,coiledv conducting-wire, as already;Y mentioned, the needle is made to incline to the other side of its quiescent or vertical positicn,

it will'point to and signify a different character, letter, figure, or symbol on thes'amc dial the electric current was transmitted, then the needle returns hy thwgravitation of itsheavy end to its vquiescent or vertical oposition,'in which it will not point to or signify any character, letter, figure, or symbol on the dial or tablet, and the needle will remain at restin tha-t quiescent or vertical'position until the transmission ot' an electric current is resumed in man,- ner before stated. And it will in most eases be expedient to affix another second magnetic needle upon the same axis as that needle already mentioned, which is ineludedin the space within the coils of the conducting-wire, as aforesaid, the said second needle bein g parallel to the former, but so far along the 'axis thereof as to he beyond or exterior to those coils of the wire within which the first-described or principal needle is situated.

rlhe second needle, which may be called the exterior needle7 must be reversed endto end in respect of the first-described or principal needle,whichinaybccalled theinteriorneedle7 -that is to say, if the north pole of one needle points directly upward when they are both iu their vertical 0r quiescent position, the north pole of the other needle must point directly downward. By this reversal of the poles the exterior needle will be in proper relative position in respect to those coils ofthe conductingwire which are .nearest to it, so as to be suitably situated for receiving the detlecting iniiuence of those coils, and therefore the exterior needle will be caused to concur with the interior needle in assuming the required inclinin g position. Also, by'their reverse poles the two needles neutralize each others terrestrial magnetism, or tendency to assume the direction ot'dipping-necdles or of compass-needles,

the two needles whenthus reversed forming what is well known by the term of au astatic combination.

The exterior needle is that which should point to the characters, letters, figures, or symbols which are marked on lthe dial or tablet before mentioned in preference to the interior needle, vwhiehi s too much concealed within the coils of the wire to be convenient for that purpose. The axis of thel two needles may pass throughthe plane ot' the said dial or tablet and .have the exterior needle 'fixed on at the front of that plane, the coils of conducting-wire and the interior needlebeing behind the same plane.

And note, it vmust be understood in all eases vnot only that the several conducting-wires with which the apparatus is provided are eifectually insulated one wire from another wire, as before mentioncd,'bnt also that the ditferenteoils which the saine wire is caused to make, as

aforesaid, around the space in which the interior needle is included, are also etfectually insulated one coil from another adjacent coil, in'

order that the electric current which is to be transmitted 'through the conductingwlre may be really transmitted-from one end of each wire to the oth er end thereof without being able to nd a shorter' course or circuit by lateraltransmission out of one coil or wire into ano-ther adjacent coil or wire'.

The requisite insulation of the wires may be made in the usual manner of preparing the wire used inthe instrument called galvanometersviz., by surrounding or covering the metal ot' the wires with coils of thread of silk or cotton or other suitable substance, an d such thread covering may be coated with some suitable resinous varnish which will be impervious to moisture.

An apparatus or mechanism containing a suitable number of magnetic needles of the kind above described (astatic or otherwise)l for pointing to or exhibiting upon a suitable dial or tablet all-the various characters, letters, iigures, or symbols which are intendedto be used in giving signals in distant places is to be provided at that portion of the apparatus which is situated at the distant terminus hereinbefore same apparatus or mechanism are to be provided at any intermediate yplaces*between the two termini, where simultaneous and like signals are required to be given. Also, another such duplicate is to he provided at the hereinbefore lrst-meutioned terminus, in view of the operator who intends to give signals in the several more and more distant places (the most remote whereof is the distant terminus) by aid of the other several duplicates ofthe said apparatus'or mechanism. .l

The conducting-wires must be arranged so that there is one such wire for each of the astatic or other needles which is contained, as aforesaid, in every duplicate of the apparatus, that one wire irst making its com-*olutions or series of coils around one of the needles 4in the duplicate which is situated at' the rst terminus in viewof the operator; thenceextending onward in continuation from the endlnost ot' those coils to the next nearest duplicate apparains, and there making like convolutions around the corresponding needle' thereof; then extending onward to the next nearest duplicate, and making like coils around its correresponding needle', and so on to that apparaltus which is situated at the distant terminus, where the same wire must also make like convolutions around the corresponding needle of that apparatus. In like manner another such conducting-wire, which is insulated from the other. wires, is extended in a similar course of ceiling round another needle in each ofthe several duplicates of the apparatus, and so with other wires, in order that every distinct needle in each duplicate may have its distinct insulated wire, but that all thecorrcsponding needles in each duplicate may be connected' by the same wire.

There may also be an additional wirejor wires extending direct from one terminus to the other without making any coils or having any connection with any needles. v

Now, if one of the before-mentioned wires which is connected with a set of corresponding needles is formed (by pressing suitable buttons or nger-keys) into a metallic circuit by conjunction with a wire which has no connection with any needles, then the electric current which is transmitted through that circuit will cause simultaneous and like motion in all the said corresponding needles, but in no others. If such current is transmitted in one direction, all those said corresponding needles will incline one way, and will all point to and signify one and the same character, letter, iigure, or symbol on their respective dials ortablets 5 but if the current'is transmitted in y'a 'contrary direction, the same needles will incline the other Way, so as to point to and signifyanother character, letter, figure, or symbol on their saiddials or tablets.

That duplicate of the portion of the appara' tus which-contains needles, and which, as before mentioned,'is placed at the terminus in view of the operator, enableshim to see what signals he is actually giving when he presses particular buttons or finger-keys, and thereby he 1n. avoid makingv mistakes.

The apparatus containing needles at the distant terminus will exhibit like signals, which v may be observed by the person who is to re-I ceive them, and so. will the several duplicates of the apparatus containing needles which may be situated at dierent intermediate places between the two termini, for, as' before mentioned, the needles belonging to every distant portion of the apparatus will exhibit the same signals at the same time.

Itis obvious that by releasing the last-mentioned buttons or finger-keys and pressing others insteadv thereof another of the beforementioned conduct-ingwires lwhich is connected with anotherdifferent set of corresponding needles from those last mentioned maybe formed into a metallic circuit with 'the same (or with another) wire which has no connection with any needles,and then the same effects as before mentioned will be produced, but upon di'erent needles, and will therefore give different signals, and .so on, any other one of those wires which, as before mentioned, is connected with a set of corresponding needles, niay,when ever it is required, be formed into a metallic circuit for bringing into operation and giving signals by the corresponding needles to which f that wire belongs; but so long as only one needle in each duplicate of the apparatus or mechanism containing needles is rendered operative at the same time, so long will the signals thereby given be confined within aseries of simple significations or two si gnications to eachneedle, according` as itis made to inclinel wires which have no connection with needles,

together with as many of thosel wires which belong to sets of corresponding needles, and V then the transmission of a distinct electric current through each such circuit, although from the same battery, will actuate two or more needles at once in each of the duplicates of `the apparatus containing needles, and it is obvious that any two of the needles contained in each duplicate may be thus brought into concurrent operation, according,

as the buttons or finger-keys are pressed; or, instead of thus forming two or more distinct metallic circuits t'or transmissionl of as many distinct electric currents, another 'and more convenient mode of obtaining the same re-v -.sult,ofactuating two needles at once, is to form a metallic circuit by conjunction of anyy two of thosecond ucting-wires before men tioned whereof each one is -connected with its own set of corresponding needles, and then the one electric current which will be transmitted through the metallic circuit sov formed will actua-te both-,such sets of corresponding needles--that is, it will actuate two needles in each of the duplicates of the apparatus containing needles--and by pressure on suitable of the buttons or finger-keys any two of the said lastlmentioned'conducting-wires may be formed into the one metallic circuit which, as aforesaid, is to bring twoneedles into concurrent and cotemporaneous operation,wherefore any two out of the whole number of needles in each duplicate ofthe apparatus containing needles may be so brought into concurrent and cotel'npora-neous operation, and that 'is done without making use of any of those other wires, before mentioned, which have no connection with any needles; but one of the latter wires must be usedfor forming part of any metallic circnit'whereby it is required to bring only one of the needles in each duplicate apparatus into operation by the 'electriccurrent which -is transmitted through'that circuit.

And in cases where it may be required 'to bring three of the needles in each duplicate of the apparatus` into concurrent and coamporaneous operation the same may be done by forming two distinct metallic circuits for two distinct electric currents, one of those circuits being formed by conjoinin g one ofthe said wires which has no connection with any .needles to one of the wires helongin g to a particular set of' needles', the other circuit being at the saine time'yformed by conjunction of two other of the llast-mentioned wires belonging to particular sets of needles; but, note, three needles in each duplicate apparatusmay the electric current through the last-mentioned halt' of its circuit will be divided between the two wires of the said couple, and, although so divided, it will actuate both the sets of needles belonging to those two wires at the same time lthat the corresponding transmission through the first-mentioned half otthe circuit will he confined to one wire,iand will only actuatc the one set of lneedles belongingthereto, thusmaking three sets of needles in' all which are ,brought into concurrent and eotemporane ous operation by transmission of only one electric current.

And not`e,it is obvious that four sets ot' needles may, if required, be brought into concur-y rent and cotemporaneous operation by transmission of only one electric current if the metallic circuit for that transmission is formed by .coupling two of those wires which belong to particular sets of needles to each pole lof the battery, in which case the transmission of the electric current through both thehalves ot its circuit will be divided betweenthe two wires of each couple, and,although so divided, it will actuate all the sets of needles belonging to all those four wires which are thus coupled, and whereof the couples are conjoined into one circuit for the transmission of one electr-ic current.

And note, in order that the conductin g-wires may be capable ot' being conjoined together, any one or two ot' them with any other one or two of them, into a metallic circuit, or into metallic circuits for the formation of a variety of such circuits', as before explained, the said wires must all (or else so many of them as are intended to retain that capability) beconnected together at the most distant terminus by one cross-piece of metal in a suitable manner for the free transmission of electric currents from that distant end of anyone wire to the corresponding end of the other wires, wherefore when the contrary ends of any one, two,or morev of the same wires (which ends are atthe rst-men tioned terminus) are Y tobe brought'by press'- ure on the buttons or linger-keys into connection with the two poles of the volt-aio battery in any of the various ways of connecting them which may be ,necessaryftorl forming the wires which are so connected into such metallic circuits as are required, it will in'all cases happen that the saidl twoor more. wires whichare sc formed into acir'cuit or into ,circuits will be alreadysuitably connected by the saidcross-piece lot-"metal at the distant termin usfor the trans mission of electric currents through those circuits; and, notwithstandingthat the said crossiece of'imetal' also forms a' communication etween the distant ends of the wires then for the time belonging to those circuits and the.

distantends of otherconducting-wires which do not for the-time belong to those circuits, nevertheless, as the last-*mentioned wires have no connection at their other ends with the poles of the battery, the vi'\,lectriccurxen t will not be transmitted (or not in any sensible degree) through -those lastmentioned wires., because the current will be confined to the other wires which are actually connected with the .poles of the battery, and which therefore constitute the intended metallic circuit or circuits. And, furthermore, the apparatus or mechanism hereinbefo're set forth, although it has been hitherto described as if it were merely for enabling a person stationed at the first-mem.

tioned terminus to give signals to other persons situated at the distant terminus, and also,'if required, at such other intermediate -places between the t-wo termini as may be provided with duplicates of that portion of the apparatus which is at the distant terminus,

municate 'intelligence in either direction for carrying on a mutual telegraphic conversation between the persons at the two termini. Thel said additions'are another voltaic battery and .set of buttons or finger-keys with suitable mechanism for them exactly like those' parts. valready mentioned as being situated at the frst-mentioned terminus. The said additional batteryand set ot' buttons or finger-keys, be-

ing applied 4to that portion ot' the apparatus which is situated at the distant terminus will enable the person whois stationed there.- to

connect the distant ends ot' auyoi the conlducting-wires withthe poles of the distant.

battery, so as to form those wires at the will of that person (according as he chooses to press the buttons or ngerkeys)'into suitable metallic circuits for tl1e.transmission of electric currents from one pole ot' the battery at the distant terminus along those conductingwires whichconstitute one half of the circuit to the other rst-mentioned terminus, and from thence back' againfalong those other conduct ing-wires which formv the other half 'of the same circuit to the contrary pole ot' the same battery, and such transmission is caused to produce all the 'same signals and diversity 'of signals by means 'ot' the ldifferent needle ,ass

.already explained, the transmission beingequally'operative upon the needles in all the severalv duplicates of the apparatus which con,- tain needles. Y

The arrangement of the buttons or fingerneedles to give a particular signal or signalsv at every portion of the apparatus containing needles, it follows from the similarity of arrangement and reversal ot' the poles of the distant battery that by pressing the correspond ing buttons or finger-keys atthe other terminus they-will cause the needles to give a like signal or signals at every such portion. Wherefore, all that has been hereinbefore explained respecting the mode ot' giving signals bya person stationed of the first-mentioned terminus to other persons stationed at the several mre and more distant intermediate placesv and at` the distant terminus is also to be understood to be equally 'applicable to the mode of giving lsignals by a person stationed at the distant terminus to others stationed at the intermediate places and at the first-mentioned terminus.

And ncte,.it is by that duplicate ot' the portion of the apparatus containing needles which, as hereinbet'ore stated, is placed in view of the person stationed at the first-mentioned terminus that he is enabled to. see and receive the signals which the person at the di'stant terminus intends to give to him.

And note, althoughin genera-l it is intended that the operator stationed at one terminus shall complete the signals or series of such which will constitute a distinct idea o r .communication from him before the person at the other terminus-begins to return any signals in reply, nevertheless the apparatus vand mechanism will admit, it required, ot' some signals being made by one party at the same time that other different signals arey makin g by the otherparty, because some of the conducting-wires maybe formed into a circuitwith the battery at one terminus, while others ot' those wiresare formed into a distinct circuit'with the battery at the other terminus, and it is obvious that distinct-electric currents may be transmitted through those circuits at the same time without interference of one with the other, and

. each of those distinct transmissions will produce its own propere'cc't upon diii'erent needles.

And note, there is a cross-piece of metal for connecting the ends of some or all 'therconductfingwires at the trstmentioned terminus similar to that cross-piece already mentioned as they niaybe required to form with the distant battery-but when such a cross-bar is provided at both endsnof each of the wires it`follows that whenever any one of those ends is to be connected with its battery in order to form one halt' 'ot' a circuit, the said end must be previously disconuectedfrom its said cross-piece. This disconnection. ismost conveniently edected by the same pressure on the button or iin'- ger-key which causes the intended connection of the'said end ot' the wire with its battery to be effected.

And before proceeding to state the inode of exciting occasional magnetism and of decomposing water, we shallexplain the detail and drawings of an apparatus and mechanism which is constructed according tothe foregoing description.,` g

v Figures A andB, Sheet I, is the dial or tablet, on which twenty letters are marked, in order to be pointed to, when required for giving signals, by tive magnetic needles, l, 2, 3, 4:, and 5, which are the external needles of as many astatic needles, whereof the details are drawn full size in Figs. C, D, E, F, and G. 6 in all thoseis the horizontal axis whereon the two astatc needles are fixedY fast, 1 being the exterior needle and 74 the interior needle, which latter is included within the numerous coils, 8,-

that the conducting-wire makes around aslight frame, 10, of `thin wood, (or ot' metal, which must not be ironV or contain iron.) The use of the frame -10 is to retain the coils in place and to preserve a narrow space within the coils for the interior needle, 7, to move in, as shown in Fig. F. The frame 10fis in two parts side by side, (seeFigs.`D and G,) leaving a small interval between them for the axis 6 to pass through, as'is shown in the horizontal plan, Fig. C, and that interval also enables the axis 6, with the interior needle, 7, to be inserted into its place in the narrow space within the coils. The two parts ofthe frame 10 are united together by their two endmost pieces passing across from one part to the other and being common to both, also'by other cross-pieces,`1`1, which serve likewise to fasten the frame l() to the back of the vertical board A in Fig. A, which forms the dial.

. The pivots at the two ends of the axis `6 are' sustained in pivot-holes formed in the ends of screws which are screwed through two horizontal Ametal bars, l2 12, one in front of the dial A and the other at the back, both bars l2 being sustained at the ends of horizontal pillars 13, which project out each way from the vertical board. AThe dial Ais very thin at the places where the coils l0 apply behind it, in order that the exterior needle, 1, which is in front of the dial A,may not be fardistant from the coils 8. The conducting-wire which `is to operate on each needle (or on each pair of needles 1 7, which constitute one astatic needle) is first coiled, as at 8, around one half of the frame 10, and then it crosses over to the other halt` and proceeds to coil around the same,

the. coils being in the 'saine direction in both. The effect ofthe two halves is nearly the same as one continuous coiling would be. The said coiled wire is copper wire closely covered with silk thread, in the same manner as isnsed for vtoo' far from the interior needles, 7, toexert a due iniiuence thereon. A lengthv ot' about two hundred yards in the coils S 8 around each interior needle, 7, and making about eight huudred convolutions, is what we have found most suitable. A

Note, in order more eft'ectually to insulate the coils ot' wire, one coil from another coil, it is bestv to line all that part of the frames 1()I with which the coiled wire will come in convtact with woven-silkcloththat is, in case those frames are made ot' metal-and also to interposc a small piece of woven-silk cloth between each successive, layer of coilswhich are laid over a preceding layer ot' coils just at the two ends ot" the iframe 10,- wl'rere the bending ot' the wirev causes the coils to apply closer to the Vpreceding coils than they do in the straight parts; also, in winding on the succeeding coils, which are to lie side by side on the frames l0, they should not be laid so close together as to press very tight laterally one against another. The tive needles, which are placed side by side ina row, being all of them astatic, as het'ore explained, do not exert magnetic influence on one another; but each astatic needle, when left to itself-that is, when left free from the influence of any electric current through the coiled wire S-will settle into a vertical position by preponderance ot' its heavy end.

The stop before, mentioned, by which the angular motion ot' the interior needle is limited when, by action of an electric current through the coiled wire S, the needle is dellected from its vertical position, is fixed at 14 to the sides of the frame l0, across that ope-ning thereof wherein the interior needle, 7, moves. Those stops must be ot' metal not susceptible of lmagnetism, and may be -wound with silk thread, to diminish any tendency of the needle to rebound when it moves suddenly toward and strikes them, that the needle may rest quietly against them. v

Note, stop-pins hxed into the face of the dial A to intercept'the ends of the exterior needle l would answer the same purpose as the stops 14. In either oase the stops must be so fixed as to limit the inclination of the needle either way to conformity with the inclning lines marked on the face of the dial-gure A,

which contains twentyletters, disposed at the several intersections of those inclining lines,

and the concurrent pointing of two of the tive needles always designatessome particular letter, which is the signal that they give by so pointing in concurrence. For instance, on the drawing needle 1 inclines with its upper endy toward the right hand, and. needle 4 inclines with its upper end toward the left hand." The mutual convergence of the upperends of those needles toward each other shows that the signal they are to give isto be found in the upper half of the dial, and the respective directions in which those two needles lpoint being continued upward by aid of thev inclined lines marked on the dial, their intersection is the.

letter B, which is the signal they now give, but if the lower ends of those needleshad converged toward each other instead of their upper ends, then the si gnalthey would give would be found in the lower halt' oi' the dial at the intersection of their respective lines of incli;

nation, at the intersection ot'which is the letter V, and so on of all the other needles; but note, this dial is onlyadapted for giving signals bythe concurrent pointing ot' two needles, and there are tive conducting-wires, 21,22, 23,24, and 25, each belongingtoits respective needle, (or pair 'ofneedles,) which constitntetive astatic needles,

1', 2,3, 4, and 5, so that there is no wire of that kind which, as before explained, is not connected with any needles, such wire being unnecessary unless it be required to give signals by inclination of only one needle, and the dial figure A is not adapted to give signals hy one needle.7

rlhe dial A and exterior needles are covered in front with a glass, and the coils and interior needles behind the dial are inclosed by boards framed to the vertical board of the dial in the manner of a close box, to keep ot't dust and dampness.

Figs. H, I, and J represent a set ot' buttons vor finger-keys whereby the person who intends to give signals in distant places can at pleasure connect thel ends of any'ot` the ve conductingwires with either ot' the poles ot'y a voltaic batterypvhich is assumed to be charged and properly prepared for action.

31, 32, 33, 34, and 35 are tive finger-keys, of metal, fixed fast by one end oi' each key. to a piece of wood, 19, which is erected on one end of the key-board 18. lThe other end of the keyIk may be pressed down, and then the key will bend like a spring, but with a tendency to rise up again when permitted. To these tive keys the ends of the five conducting-wires 21, 22, 23, 24, and25 are connected, at the fixed ends of the keys, andthe keys, being conducting bars of metal, may be considered as prolongations ot :the several conducting-wires, so that the movable ends of the keys may-be considered to be the ends ofthe conducting-wires, which have been hereinhel'ore mentioned as being occasionally connected to the'poles of the battery.V

-17 is the cross piece of metal before mentioned, for connecting those ends of all the several wires, one to another, inreadiness for forming partof some metallic circuit. The

cross-piece 17 is fixed upon legs erected upon the board 18, soV as to extend horizontally across the ends otl all the five keys, which spring upward by their elasticity soas to touch beneath the cross-piece 17, and that forms the stop to the springing up of each key. There are'two bnttons, as 4l 51, for instance,.ap

plied to each key, as 31, for instance, for the operator; to press down either one or other with his fingers, one of which buttons, 41, being pressed, will bend down the key 31, and connect that key (and consequently the conducting-wire 21, whereof it forms the end) with one pole-say the positive pole-of the voltaic battery, in consequence of the lower end of the stem of the button 41 going down in eontact with a fixed cross-bar, 26, called the polebar,7 `,which is connected with the positive pole of the battery by any suitable connecting-wire, 27, and at the same time bythe bendingV down of the key 31 its' extreme end'is disconnected from the cross-piece 17, and thereby the end of the wire 21 becomes disconnected from its previous 'connection with the other four wi res; wherefore, by pressure on the button 41, the key 31, which may be considered to ,be the end of theconducting-wire 21, is become connectedwith 'the positive pole oi" 'the battery, so as to form one-halfof a metalliccireuit, vButin order to constitute a complete metallic circuit which will transmit an electric` current, some other wire must be connected with the negative pole of the same battery, and to do that another button, (54, for instanee,)which is one ot' the buttons belonging to the key 34 of t-he conducting-wire 24 being pressed down, will bend down its key 34 so as yto disconnect the end 4thereof from the cross-piece 17, and also the end of the button 54 will go down into contact with another fixed pole-bar, 36, which is connected by a wire, 37, with the negative pole of the battery, and therefore by such 'pressure on the button 54 the key 34, which may be con-- sidered to be the end of the wire 24, is become connected with the negative pole of the same:

battery; andnote, this being done only on that setof buttons or finger-keys, Figs. lH l J',which is situated atv one terminus, the other like set of buttons or linger-keys at the other termi-nus, which are represented by Figs. 7L i j, will stand with its corresponding keys 31 and 34 in those igures(which keys maybe considered as the distant ends of the said two conducting-wires, 21`

-has just been pressed down into contact therewith, as above explained,) and thence along the key 31 of that button, and along the conducting-wire 2l ot' that key to the coils (8, Fig. G) which that wire makes around the interior 11eedle,l7, Fig. C, belonging Vto the exterior needle, 1, Fig. A; and the said transmission ot' the electric current (being in the direction from the positive pole of the battery through those coil s)'eauses the needle 1, Fig. A, to incline instantly lfrom its previous vertical or quiescent position to turn its upper end toward the right hand as far as its stop 14 will lallowit to go, and' the electric current so transmitted through the coils belonging to the needle 1 thence proceeds along all the long extension of the conducting-wire 21 to the nearest of the distant portions of the apparatus containing needles, which, supposing for a moment that there are no duplicates at intermediate places A between the two termini, will be that portion or dial and set of needles which is situated at the distant terminus, and which is represen ted edgewise Aby Fig. b, and is in every respect a duplicate otl what has been already described by Figs. A, B to Gr. At that distant terminus the electric current, which, as aforesaid, is transmitted through the conducting-wire 21,

and which wire theremakes coils around the' first needle ofthe dial, Figs. a. b, will, in passing through those coiis, incline that yfirst nee-l dle with its upper end to the right, the same as before described respecting the lother dial,

Fig. A, and tlieelectric current so transmitted through the said coils thence proceeds along the continua-tion ot' the cond netin g-wire 21, Figs. b and 7L, to the key 3l, Figs. h and fi, and along that key to the cross-piece 17, 'with which the key 31 is in contact; thence, pass'- Ving laterally through the piece 17, the electric current gets to the key 34, which is also in contact with 17 and begins its return toward the battery along the conducting-wire 24, and

thereby to the coils which that wire makes' around the fourth needle ofthe dial, Fig. b, at the distant terminus; andv the said transmission through those last-mentioned coils being in a direction toward the negative pole of the battery, causes the said fourth needle to incline with its upper end toward the left hand, and the electric current transmitted through the said coils thence proceeds along all the long' extension of the conducting-wire 24 to lreturn to the first-mentioned terminus, supposing, as before, that there are no duplicates at intermediate places between the two termini; and at the first-mentioned terminus the electric current, returning along the conducting-wire 24, is transmitted through the coils which that wire makes around the needle 4, Fig. A, and that transmission being in a direction toward' the negative pole ot' the battery, as before mentioned, respecting the fourth needle of the distant dial, Fig. b, causes the needle 4 to incline with its upper end to the left hand, as is represented in Fig. A, and.

thence from the said last-mentioned coils the electric current returns alongl the eonductin gwire 24., Fig. A, to the key 34, Fig. H, and along that key and through its button 54 (which has just been pressed down in contact with the pole-bar 36) the electric current enters that bar, and thence, by the connectingwire 37, passes to the negative pole of the battery, thus completing its long and-very intricate circuit above described, but which may be brieiiy recapitulated to be proceeding from the positive pole 27 along all the continuous extension of the wire 21, including lall the coils that it makes around needle l, Fig. A, and around the tirst needle of Fig. b to the crosspiece 1 7, Fig. h, at the distant terminus, and passing laterally by that piece 17 tothe other wire, 24, returns along all the continuous extension of that wire, including all the coils that it makes around the fourth needle of Fig. b, and around needle 4, Fig. A, to return to the negative pole 37 of the battery. vThe said long and circuitous transmission of the electric curren-t begins instantaneously on pressing down the two buttons 41 and 54'so as by their respective contacts withv the pole-bars 26 and 36 to conjoin the two wires 2l and 24-into a metallic circuit, and the needles belonging to those two wires assume their respective inclining positions almost instantaneously, wherefore they present precisely the same` appearance at the saine time on the dial, Fig. A, atene terminus, and on the dial, Fig.`b,at the other terminus, the signal which they indicate being the letter B on botlrdials; and note., vif there were duplicates ot' the apparatus containing needles situated at intermediate places between the two termini, the same would be eX'act duplicates of that which has been already described by Figs. A to G, and the conductin g-wire 21 would in passing .through each such duplicate make coils around the rst'nedle thereof, and the wire 24 would make coils around the fourth needle of each s'uch duplicate, wherefore the eiect of the electric current would be the saine on the needles in each of the duplicates, as already described rcspecting the dials at the two termini, and the same signals will be exhibitedby the needles ot'all the several dials, as well at intermediate places as at the two termini. The electric current will continue to be transmitted through the circuit so long as the two buttons continue to be pressed, provided that the battery continue in vigor, and the two needles, which have in consequence been/thrown into an inclining position,will continue steadilyin their vinclining and pointing position; but when the operator who has given them that position (in the present case that is he who is at the iirstmentioned terminus, and who has pressed the ltwo buttons 41 and 54,l Fig. H) has keptthein pressed down during a sufficient and previously appointed time for ythe person at the distant terminus to have observed the needies of the dial there, Fig. b, and to have recorded the signal which two of the needles thereof point tolthatis,in the presentcase, the first and fourth needles pointing to the letter B--then the person at the first-mentioned terminus' releases the two buttons 41 and 54, Fig. H, whereupon their keys 31 and 34 spring up by their own elasticityraising the lower ends of the stems of the buttons from contact-with the' two pole-bars 26 and 36,' andl Athereby disconnecting the two wires 21 and 24 from the poles of the battery, and the ends of the keys Bland 34 come up in contact with the crosspieee 17, that contact connects the 1 two wires 21. and 24 together; and the instant that the4 buttons are so released, the metallic circuit being therebybroken, the electric current ceases, and then the two needles of each dial which.

had been inclined by action of that current to him, or else to return an answer to what' he has received, or to make some'appointed signal in acknowledgement of the receipt, the best and surest mode of doing which will be to repeat orsend back Athe same signal he has just received as the nal signal ot'a series. For this purpose the person at the ldistant terminus has only to press the two corresponding buttons, (in this case buttons 41 and 54, Fig.h,) and they will connectthe conducting-wire 21 with'the 'negative pole of the battery at the distant terminus and the wire 24 with the positive pole thereof, and thereby the first and fourth needles will be caused to point out the letter B on all the dials, Figs. A and b, just Vas before described, because a metallic circuit will be formed and an electric current will be tramsmitted through those two .wires 21 y 54 and their needles 1 and 4in each of the several dials and duplicates thereof, is equally true ot any other two ot' the tive conductingwircs with theircorrespom'lingkeys and buttons and needles, and cannot, therefore, require further description. But note, each key is provided with two buttons, as hereinbefore mentioned, whereof one button is for connecting that key and its wire with the positive pole of the battery and the other button is forcennecting the same key and wire with the negative pole of the same battery.

,The usc of two buttons is to be enabled to cause each needle to incline either way from its perpendicular position and thereby to point to aditl'erent letter on its dial. For instance, if

the buttons 51 and 44 are pressedrdown instead ot`r41 and 54, although they belong to the saine two keys 31 and 34 and'wires21 and 24 and needles 1 and 4, as already described, nevertheless'the result will be to transmit the electric current through both those wires 21 and 24 in a contrary direction to that already described, and consequently to incline the needles in a contrary direction-that is,.needle 1 will turn its upper end to the left and needle 4 will'turn its upper end to the right-consequently their convergence or ccncurrencewill be downward, and by examination ot' the sockets independent to the key, but the extent" of that motion is limited by two slioulders on each of thc stems ot' thcbuttons, and slender springs aflixed to each key are applied to each button to bear the same upward in its` socket as far as the lowermost shoulder on the stein will allow the button to rise up from the key. The said springs ot' the buttons are more yielding` than the elastic ilexure ot' the keys; the consequence is that whenever a button is pressed it first moves down in its socket through the key bythe yielding` ot' its own slender spring without moving the key until the upper shoulder ol' the stein comes to act upon the key, and then `the further continuance ot' the pressure on the button bends down the key until the lower end of the stem ot' the button touches on the one or other of the pole-bars 26 or 35 beneath it, so as to form the intended connection ofthe key with one of the poles of the battery Ybut the other button ot' the same key, which is not pressed, being borne upward as far as it can go up in its socket through the key by its own slender spring, will not be carried down low enough by the bending ot' the key to cause its lower end to touch that polebar 26 or 36 which is beneath it. By this means there is no risk of both buttons of the saine key forming contacts at the same time unless both were to be pressed upon, which is.

theircontacts with the cross-piece 17 whenever l that contact is required, and where the coinmnnicating wires are connected to the keys the thread-covering and varnish lmust be removed and the bare metal ot' the wire held in actual contact with thel metal of the keys by screws, and the additional precaution of soldering' will be proper.. And inlike manner the junctions ot the several pieces whereof the long extension ofl each conductingwire is formed should 4be'uuited by removing the threadcovering and looping o r twisting or otherwise joining the ends, so that the metal of one connes in actual conta-ct with the metal 'ot the other, and such contact may be rendered secure by soldering, and then a covering otthread is to be wound about the joint.

The long extensions of theconducting-wires, which may be called telegraphic wires, may be lodged in channels forinedin wood rails and lined with any suitable resinous matter, with a covering-rail of wood over the channels to protect the wires from injury and from damp. Such wooden rails may be, according to the sectiomlig.V 21, Sheet III, formed in as long pieces as can be readily procured. The rail containing the wires may form the lower halt and the covering-rail the upper half of a ,square rail, which maybe fixed with one ot' its angles upward on the tops ot' upright posts fixed in the ground,in the manner very commonly y used for post-and-rail fences along embankments and other places on public roads. The rails, being lodged in 'angular notches on the tops ot' the posts, are bound down and secured therein by straps of broad hoop-ironV bended over the Lipper angle ot' the rail and reachi'ngdown the sides ot' the posts and nailed thereto. Large posts may be applied at the junctions of the pieces ot' rails to receive and sustain the adjacent ends of two pieces, and

the joint may be made firm by any suitable application ot iron.

The joints of the pieces comprising the upper half, may be interspaced to those of the lower halt, and smaller supporting-posts may be applied in the intervals between any joints.

As many parallell channels as there are conducting-wires may be cut out with circular saws along the middle part of the lower halt' of such rails, and after these rails are laid in place on their posts, andthe channels` being lined with suitable resinous varnish, then the wires,lsuitably coveredwith thread, it' necessary, and varnished, may be lodged in the channels, and iillets of wood may be driven in to ll up each' channel over *the wire, which, being thus inclosed, the upper half or coveringlrail may be applied, with felt interposed in the joint, and secured by the iron straps over the posts, and such otheriuterinediate bands of iron as will be requisite t'or fastening the two securely together like one Vrail to keep out wet and giveit suiiicient strength to resist injury;l

or the bottom yhalf may be a square rail with a covering-rail, as in Fig. 21, placed angle upward over it, that form being best for a covering, because the rain-water will not rest upon it. Fig. 22 is a section of another form of rail, containing distinct channels for the several wires,

each of which channels is closed by a fillet ot wood driven into it. Such rails may be laid un der ground when that is more convenient than to place them above ground upon posts, and some parts ot' along line may be under ground and other parts above ground, and may extend along thc sides of public roads, or railways, or otherwise, as is most convenient and suitable to go from one terminus to the other.

And tor telegraphic commrniications between places which are too distant for an electric current to be transmitted all the way with sufficient vigor to be certain in its operation, a chain ot' apparatuses, as hereinbet'ore described, must be `established to communicate one to another through the whole distance, in which case what has been called the distant terminus77 ot' one apparatus will be situated close by the commencing terminus of the next apparatus, and the signals received there from one apparatus must be sent forward by the next, and so on, all which requires noexplanation, because it is well known in the usual system of telegraphic communication, and forms no part otourpresent invention. And the same may be said. of the telegraphic language or system ot' signals and their significations. Those systems which are well known and in use for other telegraphs may be used or they may be modified, but they i'orm no part ot' our invention. And note, instead ot inclosing the several comlncting-wircs in distinct channels', as above described, they nia-yall be carried along one channel, for, provided that they are kept dry, their covering ot thread and varnish will form a sntlicient insulation et' each wire from its neighbors. rlhe whole number of coinlucting-wires may be bound together in abnndle by a wrapping of coaisethread and varnished over, thatmay, it required, be covered aga-in with a spiral tillet ot'hcmp, and then covered with pitch or tar to keep out wet. The one channel receiving a set of wires, either when so bound together ory when detached one from another, may be formed in wood rails pnt together in two halves, or in iron troughs ortubes formed ot hoop-iron bended up and put together in two halves, and united with screw-bolts at suitable intervals, having tarred felt interposed in the `joint between the two halves; or tubes may be formed by bending up hoop-iron with a sufficient longitudinal opening lett between its meeting edges to introduce the wires one by one and afterward closing up the opening by inserting` tarred felt and pinching the edges together thereon by screw-bolts applied at suit able intervals.

Fi g. 23 represents such a tube and explains how the ends of the several pieces thereof may be united by sockets ot the same description, made large enough to receive the ends of the tubes.

Fig. 24 explains how a rail ot' wood may have an inverted gutter or trough of iron applied upon it to cover over andprotect the l wires which are laid upon the wood without being let in to channels therein. The two edges of the inverted iron trough may belet into two channels cnt in the wood, and cemented in with pitch or tar, and the iron may be tastened to the wood by iron staples 'applied over it and driven into o'r otherwise fastened tothe wood. The junctions of the several lengths ot' iron may be covered over with shortlengths ofsimilar gutter-iron, but ot' larger size, to form sockets for receiving the tivo ends ot' the lengths which are to be joined; and note, the set of buttons a-nd tinger-keys represented in Figs. Ah t' j, Sheet I, are ot' exactly the same construction as what has been hereinbetore described in Figs. H, I, J, Sheet r.

And note, the apparatus represented in Sheet I (as the same has been hereinbel'ore described) mustnecessarily give all its signals by the concurrent and cotemporaneous operation of two needles, because each ot the tive conducting-wires makes coils around one ot1 the five needles in each dial; and whereas two.

wires must ot' necessity' be employed to form any metallic circuit, it follows that whichever two ot the five wires may be so employed they must bring two needles into concurrent and cotemporaneous operation. Wherefore, in order to give signals by operation ot' one needle at a time, another or sixth wire may be added to eXtenfLdirect from one terminus to the other without forming coils around any needles, and the two ends of that sixth wire must be vconnected to a sixth key, which isfadded to l the set of keys at 'each terminus, that key having its two buttons precisely the same as all the others. Then it'is obvious that the appa ratus will be qualified for operatingl at pleasure upon one needle at atime as well as upon two needles at a time, as already described,or upon three needles at a time, or upon four at a time, or u on five at a time, for each set of buttons and keys will consist, as before, of two rows of buttons, those in one row being` adapted on pressure to cause the needles belonging to them t0 incline and point in one-direction, the buttonsin the other row on press. ure causing the same needles to incline and point in a contrary direction, all which is as before described; but, now, instead of tive, there are six such buttonsin each row, the additional key, with its two butt-ons, may be disposed 4at the commencement of the series or ve already described-that is, by the side of the first key, which is marked 3l iu Figs. H and h, Sheet l, and its two buttons are marked 4l 5l-the additional key may be marked 30, its two buttons 40 and 50, and the additional or sixth wire 20, and they may. be considered as the blanks or zero of the series; and vit is obvious that on pressing down either of the blank buttons 40 or 5() no needles will be moved in consequence of so pressing, but by pressing down at the same time any other one of the buttons the particular needle thereto `l'oelonging,will be moved by itself alone, and

that one way or other, according to the row in which the buttonithat is pressed is situated.

'The dial, Fig. A, as it has been already described, containing twenty letters, none of them can be pointed out by singleV needles, but a row of numeral figures may be marked in red ink, as there shown, and it will be ap parent that when only one needle is inclined at a time it will point to some one of the red gures 1 2 3 4 5 6 7 8 9 0 on the dial, and not to any of the letters thereon, and if thought more convenient such numeral characters may be marked in red around the border or margin of that part of' the dial which contains the letters.

Butnote, in cases where the use of six conl' ducting-wires may be objectionable on account of the expense of very long lines thereof, ve wires and five keys, with ten buttons, as beforedescribed, and as represented-by Figs. H;V

and h, may be retained exactly, but the fth key,v 35, and wire 25 will be the blank, which has no connection with4 any needles, and `one o f lthe five needles of each of the dials willmbe omitted, and only four of them used, 'with a.'

suitable dial, such as is represented by Fig. Z, Sheet HI, which dial is adapted to give significations by the pointingof any one needle as vwell as by the concnrrent'and cotemporaneous pointing of two needles.

And now, respecting the means of applying the attractive force of occasional magnetism which may be excited in masses of iron by electric currents, as hereinbefore alluded to- Fig. Y, Sheet I, represents a Inode of actuatinga magnetic needle, 7, which may, for the;

present, be supposed to be one, of those belonging to the dial, Fig. A, and that the parts represented in Fig. vY are placed at the back,

of the vertical board of the dial A, in place ot' the frames 10, represented in Figs. D to G5. U U, Fig. Y, are two pieces ot' soft malleable iron, bended into the form ot' a fork or-of the letter U, or what is termed a horseshoe form,77 one such horseshoe being over the needle 7 and the other under it, but both being in the same plane in which` the needle is to move. The four extremities of the two horseshoes come very near to the ixed stops 14 14, by which the inclining motion of the needle 7 either wayis Ito be limited, in manner already explained. l

21 is the conducting-wire by which the nee` dle 7 is to be actuated. That wire is covered with silk, as before explained respecting Fig. Gr, but it is now wound in continuous spiral coils around the four ends or prongs of the two horseshoes, U U,-that is to say,the wire of coils, t, around one prong of the lower horseshoe, and then passes across to form a like mass of coils, e, around the other prong, and from the last of those coils the wire 21 continues in its course of extension, in the same mannerasif it had formed coils as before explained by Fig. Gr. When an electric current is transmitted through thel wire 21 and all its several coils r s t c, magnetism will,

is transmitted .in the contrary direction it will cause the-needle 7 to incline the other way;

or, if the electric current is discontinued, then the two horseshoes will cease to be magnetic, and will allow the needle to return to its quiescent or vertical position by the gravitation of its `lowerend, which must be heavier than its 'upper end, as already fully explained' respecting the needles having heavy ends wherefore the effects produced upon the needle by the means explained Ain Fig. Y will be similar in every respect tothe effect produced thereon by the means hereinbet'ore described in respect to the Figs. D to G.

And note, the two horseshoes U U are to be `fixed fast to the back of the vertical board A by any convenient means, but the'four extremities of the prongs of the horseshoes U U must not'be so situated as to be too near to the ends of the needle 7 when the same is inclined as far either `way as its stops 14 will allow it to go, because the magnetic attraction ot' the needle itself for the iron ends of the horseshoes (although that iron has ceased to be magnetic) might, if they cametoo nearto gether, impede the free return of the needle to its vertical position by the gravitation of its heavy end. And note, the needle 7, Fig. Y, corresponds to the interior needle 7, Fi gs. E, F but the exterior needle belonging to Fig. Y, which is to be in front oli the dial, is to he a mere pointer, of brass or copper, and not a magnetic needle, wherefore the needle actuated in the manner of Fig. Y will not be according to an astatic combinatiomwhich it is advisable for the needles Figs. E F to be, as already explained. And respecting the sounding of .alarms in distant places by means of electric currents transmitted through metallic circuits, the same may be effected' by the attractive force of occasional magnetism excited in masses of iron by such currents, and may be applied in a distinct apparatus which is only adapted for sounding alarms without giving any other signals than such alarms. (See Sheet II.)

Fig. Rn is a well-known piece of clock-work, having a bell, g, which is sounded,when required, by a hammer actuated by the wheelwork, that wheel-work being turned by force of a spring or a weight, with a cord and barrel which has been previously wound up, but all motion ot' the wheel-work is stopped by a detent, p, mounted .on a horizontal axis, L, catching into the teeth of any of the wheels l, as will best'snit; and when that detent p is removed out of the way of the teeth ot' the wheel Z, then the alarm begins sounding` its bellall which is so well known as to require no furtherexplanation, particularly as there are or maybe various constructions of such alarms. Our improvements therein only relate to the mode of disengagingand re-engaging such detentp by means of electric currents.

Let K represent a voltaic battery on any of the constructions commonly usedand one vot the most simple, consisting of a fiat vessel coils the continuation of the conducting-wire- 21, Fig'. R, is extended to such place as is most convenient and accessible to the person who intends to sound the alarm, and there the said wire 21 is connected to a finger-key, 31, which is fixed fast by one of its ends, and the other end is capable of beingbended down by pressure to bring it down into contact with a pole-bar, 26, which is fixed beneath it, and from which another conducting-wire, 22, proceeds to the other (which is in this case the negative) pole,37, of the battery K. When the key 31 is not pressed it springs up by its own elasticity so as notto touch its pole-bar 26, and no metallic circuit isi'ormed, and so lon g as that is the'case the detentp ofthe'aiarm is kept by action ofitsown spring, mjin the way otl the teeth of the wheel l, so as to prevent the alarm from sounding; but there is a mass of soft malleable iron, V, tixed across the lever'or tail end otl the detent p and extending horizontally across parallel to the axis k ofthe deteut, the two ends of the piece of iron V being opposite to'and at a' small distance from the ends of the two prongs ofthe horseshoe U, as is shown in perspective atFg. S, Sheet Il; but neither the piece V nor the horseshoe U being magnetic they do not attract each other.

The person who intends soundiu g the alarm can do so by merely pressing vdown the key 31, which he may either do by applying his hand or finger to the key 31 or by pulling down a cord or bell-pull, w, which may be appended to it. In either case, by bending down the key 31 vto touchits pole-bar 26 the required circuit is formed, and an electric current being transmitted through the conducting-wire 2],

which is coiled round the prongs ol the horseshoe U, it excites magnetism therein or converts it for the time into a voltaic horseshoemagnet, which attracts theA piece of iron V at the lower end of the detent p and draws it toward theend of thehorseshoe U,` although it is not allowed to touch them. rThe upper end of the detent is thereby withdrawn from out ot the way of the wheel l, and then the alarm commences sounding or hammering its bell by its own action derived from its previously-wound-up weight or spring, and if the key 31 is kept down so long, the alarm will continue to sound until its said weight or spring is run down; butit' the key 3l is released, so that it can spring up andseparate from its pole-bar 26, then, the circuit being broken, no electric current will be transmitted through the coils ofthe wire 21, and the temporary magnet ism ot' the horseshoe U will cease'altogether, and it will no longer attract the pieceofiron V, but the spring mot' the detentp will withdraw the piece V from the horseshoe U, and will bring the upper endot the detent p into the way of the teeth ot' the wheel Z, so as to stop themotion thereot',and consequently thesounding of thealarm.

And note, in order that no adhesion may take place between the ends of the piece ot iron V andthe iron ends ot' the horseshoe U, v

it should not, as before mentioned, be allowed to actually touch those ends, which may be managed by suitable stops to limit the motion of the detentp about its axis k; or else two small copper studs may be tlxedinto the ends ofthe horseshoe, orinto the ends ot' the piece V, to form prominences of copper, which may be lallowed to come in contact, and they will preveut the contact of the iron with the iron 32 26. Fig. lt shows a duplicate key and polebar, which'may be provided in another di'erent place from those alreadydescribed at 31 and 26. The key 32 having abranelri'rom the conducting-wire 21,*and its pole har 26 having a like brauch to the conducting-wire 22, they will. give the means ot' sounding the 'same alarm from that different place as well as from thel place first mentioned, and so on as many other' keys and pole'bars as may be required may bev provided at different places for sounding the samealarms.

The said apparatus, Fi g. R, may be applied in dwelling-houses, inns, theaters, or other large buildiugs,tor the same purposes as the it, in order lo strike against and sound the bell q, in the manner represented in perspective, Fig. S, by a 'direct action of the force of the occasional magnetism which is excited in .the v the detentip from the teeth of the wheel Z. In

such situations the apparatus Fig. S is to be `preferred, wherein the voltaic battery K and the iron horseshoe U, together with the piece ot' iron V at the lower end of the detentp, are -all the same, as already described respecting Fig. R, and the hammer for sounding the bell q of the alarm may be either at the upper end of the tetentp,.as representedv in. F-ig. S, `or else the hammer may be moved by clock-work,

r"as already mentioned, apd as is represented in Fig. R, the office of the upper end of the detent p being in that case to catch the teeth of the wheel L, in order to prevent the sounding of the alarm until the dctent is removed, as already explained. But instead of forming a longmetallic circuit, to extend all the way from that battery K tothe distant place or places where the person who attends to sound the alarm may be situated, and -thence back again to the battery K, as isl the case in Fig. lt, the battery K, as is the case in Fig. S, is devoted solely to the purpose of excitingoccasional voltaicrnagnctism in the horseshoe U by transmission of an electric current through no greater lengthof metallic circuit than is most suitable for that purpose-that is to say, a considerable part of the length is accumulated in the coils around the prongs of the horseshoe U; The electric'current which is to he transmitted through the long circuit which extends to the said distantrplaces is derived from adistiuct batter-y, M, Fig. S, and that currentdoes not operate directly upon the alarm,

but it causes theother battery, K, (which may for distinction b'e called the alarm-batteryb to be brought into action in order that it may sound the alarm, in manner already explained It may therefore be considered that the bati tery M and the electric current which is transmitted from it through the long metallic circuit formed by the two conducting-wires 24 25 is caused to produce the same eiect ou the alarm apparatus as has been already described to be done by pressing down the key 31, Fig. R, in contact with its polebar 26, viz: It esi tablishes the requisite contact between the en ds of the wires 2l and 22, Fig. S, to form them into aj metallic circuit for the transmission of au electric current from the positive pole 27 of the battery K along the wire 21 and through the coils which that wire makes around the two prongs of the horseshoe U and back again along wire 22 to the negative pole 37 ofthesame battery K. This connection is eected by caus ing the two ends of a small fork, 60, Fig. S, to

descend into two small cups, 61 62, formed atthe upper end of ltwo upright pillars, 21 22,

which may be considered as prolongations of' the wires 21 22.

A small quantity of mercury is con-tained in each of the cups 61 62, and when the fork 60 is brought down to dip therein, as is representedby dotted lines, it forms the two wires, 21 and 22, into a metallic circuit, and that will cause t-he alarm to begin sounding the same as would follow from pressing` the key 31, Fig. R; but when the fork 60 is raised up, as represented iu Fig. S, that circuit is broken and' the alarm ceases to sound in the same manner as would follow from releasing the key 3l. v

This being understood, itis easy to explain how the small fark 60 is brought down or raised up by the motion which is given to a magnetic needle by transmission of an electric current from thevdistaut battery M through a long metallic circuit, which may be formed, when required, by the long wires 24 and 25. The

fork '60 is formed out of one end of a slender lever, 63 64, which is fixed on the horizontal axis65 of a magnetic needle which is placed within a set of coils, 8, which the wire 8 makes around a frame, 10, in the same manner as al ready described respecting Figs. D, G, Sheet I, the only difference from the structure there represented'being that the axis 65 of the needle, instead of being mounted ou pivots at its ends, is suspended by the tension of horsehairs, `which are extended horizontally inl prolongation of the axis 65 from each end thereof' to small regulatingscrews 66 66 'supportedy at the npperends of two small standardsi 67'., which are erected on the same wooden base as the uprightA pillars 21 22 for the cups 61 62, andtheframe l0 for the coils 8 of wire is also erected onthat same base; also, thatframel 10,v instead of being made in two parts, as is representcdby Fig. D, and as before explained,

is here represented in one part, with a small tube projecting ont horizontally to admit the axis 65 of the needle and keep the coils of-wire Sjapart out of the way of the axis 65. I

lhe lever 63 64, which carries the fork l60,

-isv fixed-on the axis 65 at right angles thereto,

and also at right angles to the magnetic nee d'le, which latter is concealed in Fig. S Within the frame 10. The end 64 of the lever 63 64 has a small weight, which overbalances the weight. of the fork 60, so as to raise the same up out of Ithe cups 6l 624 as high as the stops 14 will permit whenever there is no electric current transmitted through the coils'8 8; but

the twoends of therwire 8 composing those coils are connected at 75 76 with'the ends of thev two long conducting-wires 24 and 25,as is clearly shown in Fig. S. The wire 24 is connected with the positive pole 87 ofthe battery M, i

and .from .the negative pole 97 of the' same'battery a connecting-wire, 36,extends to the tinger-key 3l, and to the pole-bar 26 beneath that key the" 'wire 25 is connected; wherefore, if

-the key 31'is pressed down into contact with its polebar 26, the two lou g conducting-wires 24-and 25 will become united intoa metallic circuitfor the Itransmission' of. an electric curr rent ythrough the following course, viz: From the positive pole 87 of the battery M along the long conducting-wire 24 to the button 75, and

thence throughvthe wire 8, which is coiled around the frame 10 in the space whereof the magnetic needle is situated, and continuing from those coils to the button 76 there ,enters the other long conducting-wire, 25, and alongrv that to the pole-bar 26, and through thatand its key 31 and connectingwire 36 to the negative pole 97 of the battery M, and the said transmission through the coils'S causes the magnetic needle to incline from its perpendicular in the proper direction, and so much as is requisite to put the fork 60 down into the cups 61 62, which, as already stated, will cause the alarm to begin sounding by the action already fully described in respect to Fig. It; but when the key 31, Fig, S, is. released, then the said metallic circuit is broken, whereupon the electric current, lceasi n gto be transmitted through the coils 8, ceases to influence 'the magnetic nee(lle,and therefore, by the preponderance of the weight 61, the fork 60 is raised up out of the cups 61 62 as highas the stop'14 will allow, and then thcsounding of the alarm ceases for the reason alreadycxplained in respect to Fig. 1t; and note, it is obvious that the weight or spring which actuates the clock-work ofthe alarm might as that weight descends `or that spring unwinds be made to pull a string which is tied around the wrist of a person who is,

vbecause the person who intends giving"sig nals in distant places can first call the attention of -his correspondent or correspondents at the distant places by sounding the alarm or alarms previously to commencing, giving visible signals. For this purpose an apparatus with an alarm, like Fig. S, but constructed and adapted to be actuated with clock-work, as in Fig. R, is to be provided at each terminus or place where there is a set of buttons and finger-keys, Figs. H, I, J or Figs. k, j, Sheet I, and also at each intermediate place where duplicates of the dials with needles may be situated; but` the llong conducting-.wires 24 and 25, Fig. S, together with the vbattery M and finger-key 31 and pole-bar 26, are not required, because the functions of those parts are'to be performed by twoof the iive long conducting or telegraphic wires-viz., 2l and 25, Sheet I-together with their sets of buttons and finger-keys; for it is evident that the sounding of the alarms may be performed by transmission ofthe same electric current which produces ,some particular signal-'for 1nstauce,

that convergence of the upper ends of needles? i and@ which signifies the letter A on the dial Fig,L A, and which is occasioned by the' transmission of an electric current through the wires 21 and 25 and their keys 31 and 35 but aslit would be inconvenieut'to suffer the alarms to be sounded everytime when the signal-letter-A is .to be exhibited, the alarm should be only kept connected with those two wires in the intervals between the making of telegraphic communications when the apparatus is not in use and ou proceeding. to resume the use of it for .giving signals.l The prelude or first thing willbe for the person at the rstmentioned terminus to make'the signal for letter A by pressing down buttonstl and, which, producn g all the saine results as press-n ing down the key 3], Fig. LS, in the manner already fully described, will begin sounding the alarm at the distant terminus, and also those at -the'in termediate places, those buttons 41 andbeing held down only a very short time and then released; and the soundin g may be repeated,if necessary, until the attention ofthe person at .thedistant terminus'is called toit, and "as soon as lie is ready to receive signals he'y will .communicate ,that fact by sounding the alarm at the first-mentioned terminus, which he'does by pressing the buttons 41 and 55 ,Fig.1i and by those means a mutual understanding will' have been establish/ed between the two persons that they are both prepared to commence' a telegraphic communication, he who commenced by tirst sounding an alarm having the right of precedence-therein, and then, the alarmsv being unnecessary for the present, each person may disconnect his own alarm from the telegraphic wire; but that is merely to avoidv the annoyance of itslbeing sounded every time the signal-letter Ais made by either` 'personinthe course of their communication; but when the person who has, as before stated, acquired the right of precedence therein intends to put anend to it forthe prescnt, he expresses that intention by some unusual signal which has been previously agreed upon-such, for instance, as pressing down at once two of the buttons 41 42 in one row and two of thebuttons 54 55 in the other row, which will turn theupper ends of the needles 1j and 2 to the right and the` needles-4 and 5 to the left, and immediately after the 'making of. such A'signal it is to be imperative on 'each person to lconnect his alarm with the vtele- -graphic wires and to wind up its clockwork weight or spring, lif neo safety', 1n -ord'erthat the alarms may 'never f i-l-of be ng ready for sounding during all cessations, however short,

in the ltelegraphic conversation, andin order that every resumption ofthe conversation may be p rcluded by sounding an alarm. And as to the'several alarms at intermediate places between the two termini, they will all begin to be sounded at the same time with that valarm at either of the two termini which is first sounded, and the persons who are stationed at those intermediate places, on hearing the 'sound and



Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102015200042A1 (en) 2015-01-06 2016-07-07 Volkswagen Aktiengesellschaft Bi-directional communication in the vehicle
US9812825B2 (en) 1998-04-10 2017-11-07 Chrimar Systems, Inc. Ethernet device

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9812825B2 (en) 1998-04-10 2017-11-07 Chrimar Systems, Inc. Ethernet device
DE102015200042A1 (en) 2015-01-06 2016-07-07 Volkswagen Aktiengesellschaft Bi-directional communication in the vehicle
DE102015200042B4 (en) 2015-01-06 2018-09-06 Volkswagen Aktiengesellschaft Bi-directional communication in the vehicle

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