THE LEVER KEY.
This, as we have said, is the most simple form of the key, or correspondent. It is a modification of that shown atfigure 11. The following figure,21, represents a key, where the lever is taken advantage of to make a more perfect connection, with less application of power. A key of the above form has been used during the past winter for reporting the proceedings of Congress, and has been found tooperate with ease, with certainty, and with great rapidity. A A is the block or table to which the parts are secured. E represents the anvil block. J the anvil, screwed into the block, both of brass. B is another block, for the stop anvil, K, and the standard for the axis of the lever C. L is the hammer, and is screwed into the lever, projecting downward at V, almost in contact with the anvil, J. R is another screw of the same kind, but in contact with the anvil, K, when the lever C is not pressed upon. Under the head of each of these two screws, are tightening screws, which permanently secure the two hammers, to any adjusted position required for the easy manipulation of the lever, C. D is a spring which sustains the arm of the key up, preventing the hammer, L, from making contact with the anvil, J, when not in use. G is a screw connecting with the brass block, B, and F a screw connecting with the block, E. To these screws the two wires, I and H, of the battery are connected. Now, in order to put it in operation, it is necessary to bring the hammer, V, in contact with the anvil, J, for so long a time, and at such regular intervals as are required by the particular letters of the communication. When the key is pressed down, the fluid passes from the battery to the wire, H, then to the screw, G, then to the block, B, then to the lever, C, at the axis, S, then to its metallic anvil, J, then to its screw, F, then to the wire, I, and so to the battery.
Fig. 21.
Fig. 21.
In order to give some idea of the rapidity with which the circuit may be closed and broken, and answered by the motion of the lever, a figure,22, is here introduced to explain its construction and arrangement. The platform is shown at T, and the upright at S, to whichthe coils of the electro magnet, A, are secured by a bolt with its thumb-nut, E. D a projecting prong of the soft iron, and C the armature attached to the metallic lever, B, which has its axis or centre of motion at K, in the same manner as the electro magnet of the register; R being the standard through which the screws pass. O is the steel spring secured to R, by a plate, U, upon it, and the screw, N. L and M are adjusting screws, for the purpose of confining the motion of the lever, B, within a certain limit. P is a wire with an eye at the top, through which the end of the steel spring passes, with a hook at the other end, passing through the lever. The wire, Q, from one of the coils is connected with the plate, U, at the top of the standard, R. As the standard, R, is of brass, the plate U, the axis of the lever of steel, and the lever, B, of brass, all of them being metals, and conductors of the galvanic fluid, they are made in this arrangement to serve as conductors. I is the wire proceeding from the other coil, and is extended to one pole of the battery. The wire, H, coming from the other pole, is soldered to the metallic spring, J, which is secured to the upright, S, by means of the adjusting thumb screws, F and G. This spring is extended to J, where it is in contact with the lever, B. We have now a complete circuit. Commencing at I, which is connected with one pole of the battery, from thence it goes to the first coil; then to the second; then by Q to U, the plate; then to the standard, R; then to the steel screw, K; then to the steel axis; and then to the lever to the point, J; where it takes the spring to H, the wire running to the mercury cup of the other pole of the battery.
Fig. 22.
Fig. 22.
The battery being now in action, the fluid flies its circuit; D becomes a powerful magnet, attracting C to it, which draws the lever down in thedirection of the arrow, X. But since B and J are a part of the circuit at V, and since, by the downward motion at X, and the upward motion at V, the circuit is broken at J, the consequence is, that the current must cease to pass, and D can no longer be a magnet. Hence the lever at V returns, coming again in contact with J. Instantly the fluid again passes and the lever at V separates from J. Again the fluid ceases to pass, and the lever again returns. By this arrangement, then, the lever breaks and closes the circuit, and it does it in the best possible manner to show how rapidly the magnet can be made and unmade. When its parts are well adjusted, its vibrations are so quick that no part of the lever is distinctly seen. It appears bounded in size by the limits of its movement up and down, and the motion is so rapid as to produce a humming noise, sometimes varying the notes to a sharp key. In this way it will continue to operate so long as the battery is applied. We infer from this, the almost inconceivable rapidity, with which it is possible to manipulate at the key of the register in sending intelligence, far surpassing that of the most expert operator. This arrangement of the electrome, was devised by Mr. Vail in the summer of 1843.[8]
After the close of the session of Congress in the spring, 1844, a series of experiments were commenced by the request of Prof. Morse, under the direction of Mr. Vail, for the purpose of ascertaining what amount of battery was absolutely required for the practical operation of the telegraph. From the first commencement of its operations to the close of the session, so anxious were the public to witness its almost magic performances, that time could not be taken to put it in a state to test either the size of the battery required, or bring into use all the machinery of the register. On that account, butone wirewas used during that period for transmitting and receiving intelligence, and the capabilities of the instrument were shown to some disadvantage; requiring the constant attendance of those having charge of the two termini.
This first experiment made was to ascertain the number of cups absolutely required for operating the telegraph. Eighty cups had been the number in use. Upon experiment, it was found, that two cups would operate the telegraph from Washington to Baltimore. This success was more than had been anticipated and urged on further experiments, whicheventually proved that the earth itself furnished sufficient galvanic power to operate the electro magnet without the aid of a battery. In the first experiment, a copper plate was buried in the ground, and about three hundred yards from it, a zinc plate was also buried in the ground. To each of these plates a wire was soldered, and the ends brought into the telegraph office, and properly connected with the key and electro magnet of the register. The battery not being in connection. Upon manipulating at the key, it was found that the electro magnet was operated upon and the pen of the register recorded. This led to another experiment upon a more magnificent scale, and nothing less than that of using the copper plate at Washington, and the zinc plate at Baltimore, with the single wire, connecting those distant points, and the battery thrown out. Here, too, success followed the experiment, though with diminished effect. By the application of a more delicate apparatus theElectro Magnet[9]was operated upon, and the pen of theregistering instrument recordedits success. From these experiments, the fact appears conclusive, that the ground can, through the agency of metallic plates, constantly generate the galvanic fluid.
Fig. 23.
Fig. 23.
In the above figure,23, let the right hand side represent Washington, and the left, Baltimore. The lines marked 1, 2, 3, 4, 5, and 6, betweenmandk, respectively, represent the six wires connecting (for example) Washington with Baltimore. Each cluster of black dots, P and N, represent the batteries of that line upon which it is placed. There are three batteries at W, and three at B;m1,m3, andm5, represent the three magnets, or registers, andk2,k4, andk6, the three keys, or correspondents, at Baltimore;k1,k3, andk5, are the three keys, or correspondents, andm2,m4, andm6, the three magnets, or registers, at Washington. C B is the copper plate at Baltimore, and C W, the copper plate at Washington, one at each terminus.
In order to operate the six lines, simultaneously, if required by the pressure of telegraphic communications, there must be three operators at each station, commanding their respective keys, and presiding at their respective registers. If the three operators at Washington choose to write in Baltimore, together, or in succession, on their respective registers at the latter place, the galvanic current of the three lines 1, 3, and 5, takes this direction. Commencing at the point, P, of the three batteries, 1, 3, and 5, at W, it passes tok, of the keys; thence along the wires tom, the magnets, 1, 3, and 5 at B; thence to the single wire, where the three currents join in one to C B, the copper plate; then through the ground to C W, the other copper plate; then up the single line to their respective batteries at the point, N, having each finished its circuit independently of each other.
If, in reply, the three operators at Baltimore wish to write upon their registers at Washington, either together, or in any succession, they may choose; the fluid leaves the point, P, of their respective batteries, at Baltimore, 2, 4, and 6; unite in the single wire to C B, the copper plate; then pass through the ground in the direction of arrows to C W, copper plate at Washington, then along the single wire to their respective magnets,m, 2, 4, and 6; then along the extended wires tok, 2, 4, and 6 at Baltimore; and then to N pole of their respective batteries. In this manner six distinct circuits may be operated independently of each other, at the same time, or in any succession, with only one wire for each, and the ground in common, as a part of the circuit.
It is obvious from the above arrangement that if one wire only, extended between two distant points, will suffice to enable communications to be exchanged with each other; that any number of wires extended, will also, each, individually, give a distinct and separate line for telegraphic purposes, independently of all the other lines on the same route.
Fig. 24.
Fig. 24.
Infigure 24, the same arrangement of wires is observed as respects their number, and the situation of the keys and magnets; but, with this difference, that instead of six batteries, one for each wire, there is but one, which is placed upon the single wire, with which the six wires join. The battery is represented by four black dots, marked N B P. The course of the fluid in this case is from P to C, the copper plate on the left side; then through the ground to C, the copper plate on the right; then through the single wire to any of the six wires, which may be required, then to the single wire on the left side to N, of the battery. It is obvious that in this arrangement there is a division of the power of the battery, depending upon the number of circuits that may be closed at any one instant. For example: if circuit 1 is alone being used, then it is worked with the whole force of the battery. If 1 and 2 are used at the same instant; each of them employ one-half the force of the battery. If 1, 2 and 3 are used, then each use one-third its power. If 1, 2, 3 and 4, then each circuit has one-fourth the power; if 1, 2, 3, 4 and 5 are used, at the same moment, then one-fifth is only appropriated to each circuit, and if 1, 2, 3, 4, 5 and 6, then each employ a sixth part of the galvanic fluid generated by the battery.
The great advantage which this telegraph possesses in transmitting messages with the rapidity of lightning, annihilating time and space, would perhaps be much lessened in its usefulness, could it not avail itself of the application of a secret alphabet. We will now proceed todescribe some of the various systems by which a message may pass between two correspondents, through the medium of the telegraph, and yet the contents of that message remain a profound secret to all others, not excepting the operators of the telegraphic stations, through whose hands it must pass.
For this purpose let the telegraphic characters representing particular letters be transposed and interchanged. Then the representative ofa, in thepermanentalphabet, may be represented byy, orc, orx, in thesecretalphabet; and so of every other letter. As there are twenty-seven characters in the telegraphic alphabet, they can, by transposition, furnish six hundred and seventy-six different kinds of secret alphabets; nearly two for every day of the year. Two persons have agreed to use, in their telegraphic correspondence, the secret alphabet. From the six hundred and seventy-six combinations, they have selected one for each day in the year, and given each their particular date. In the course of their business, it becomes necessary on the first of July, for one to transmit important information to the other. He then refers to the telegraphic book, for the alphabet belonging to that date, and from it writes his communication, as follows:The firm of G. Barlow & Co. have failed.He runs his eye along the alphabetical column fort, and finds that for the first of July it ise, thathisj,eisn, and in the same manner, he proceeds with the remaining letters of his message, which, when completed, reads as follows:Ejn stwz ys & qhwkyf p iy jhan shtknr. As every person employing the telegraph has his name, occupation and place of business registered in the record book of the office, with his telegraphic number, we will suppose, thatMr. Hammond, Builder, 57 Anson-st. Philadelphia, sends the above communication to the office forMessrs. Talford & Co. Lumber Merchants, 41 Bradford-st. New York. In the record, the former name is numbered 14; and the latter 31. The private message is then directed thus,No. 14 to No. 31, and reads thus: Mr. Hammond, &c. sends the following communication to Messrs. Talford & Co. &c. “The firm of G. Barlow & Co. have failed.” This message, in substituted characters, is copied at the receiving station, and immediately delivered. The messenger returns with the following:Syw fjhe hzyxce.To which is prefixedNo. 31 to No. 14. This is sent to Mr. Hammond, who, on translating it, discovers that it must be answered by figures. He then refers to the secret numerals, under the date of the first of July, and finds the private numerals required are 897, 312, adding to it a few letters, when it reads thus,No. 14 to No. 31, 879, 312 rykkm. If it should happen, that on the 6th of December, or 13th of May, it was necessary to send a private communication, the secret alphabets of those dates are used, and so for any date of the year.
The transposed secret alphabet is not perfectly secure for private messages, when the message contains more than eight or ten words. It is, therefore, necessary to adopt some of the following modes of making it perfectly incomprehensible, and beyond the power of any person to decypher it. Any one or two, or more, of these modes may be selected and combined for this purpose. Let the following key or transposed alphabet, be used in illustrating the following rules:
1st. Let the last letter of a word remain unchanged, viz.Rome, transposed,lqde.2d. Let the first letter of a word remain unchanged, viz.Rome, transposed,rqds.3d. Let the first and last letter remain unchanged, viz.Rome, transposed,rqde.4th. Let the middle letter of a word of 5, 7, 9 or 11 letters remain unchanged, viz.First, transposed,xwrfo, and in words of 4, 6, 8, 10 or 12 letters, let the two middle letters remain unchanged, viz.Rome, transposed,loms.5th. Let the first, middle, and last letters of a word remain unchanged, viz.first, transposed,fwrft.6th. Let the middle letter of words of 5, 7, 9, 11 or 13 letters commence the word, viz.first, transposed,lxwfo.7th. Let the two middle letters of a word of 4, 6, 8, 10 or 12 letters commence the word, viz.Rometransposed,qdls.8th. In a word of 4, 6, 8, 10, 12 or 14 letters, let the first half of the word be substituted for the last half, viz.Rome, transposed,dslq.9th. Let every other entire word be reversed, viz.What is the news, transposed,ntro fw ots fns&.10th. Let every third word be reversed.11th. Let every fourth word be reversed.12th. Let every fifth word be reversed.13th. Let the three middle letters of every word of 5, 7, 9, 11 or 13 letters be reversed, viz.first, transposed,xflwo.14th. Let every word of two or three letters be prefixed to the beginning of the following word, or affixed to the end of the preceding word, viz,State of Maine, transposed,forosqx drw&s.15th. Let one, where double letters occur in a word, be excluded, viz.willtransposed,nwv.16th. Where two or more words, of two or three letters, follow each other, let them be joined together, viz.Cotton is on the rise, transposed,zqoq& wfq&ots lwfs.17th. Make no separation between words of less than eight letters, viz.Cotton is on the rise, transposed,zqoq&wfq&otslwfs.18th. Make no separation between words.19th. Reverse the order of the letters of the whole message, viz.Cotton is on the rise, transposed and reversed,sfwl sto &q fw &qoqz.20th. Change the key, alternately, every ten or fifteen words, using two keys.21st. Let the two first letters of all words of four letters be affixed to the end of the preceding word, and the remaining two letters be prefixed to the word following, viz.stocks have fallen, transposed,foqzuftr gsxrvs&.22d. Change the key irregularly, thus, for example, the first three words transpose from one key; the next three words from another key; the next three from another key, and so on.23d. Reverse the termination of those words ending withtion,sion,ness,less,tive,ty,ly,ed, &c.24th. Make a division of long words into two.25th. Let those words which occur frequently and have only two or three letters remain unchanged, viz.to,a,the,of,and,for,with, &c.26th. Let every two words, or every three, or every four, be reversed.27th. Omit one vowel in every word.28th. Omit the lettereat the beginning and end of a word.29th. Omit the letterioryat the beginning and end of a word.30th. Omit the letteroat the beginning and end of a word.31st. In words of 4, 6, 8, 10 or 12 letters, let the first of the two middle letters commence the word, and the last of the two middle letters end the word.32d. Lettsignifythe;eforof the;fforof;uforyou;wiforwith;iforby;ttforthat;tsforthis;frforfrom;nfornoornot;wforwill;tdforto-day;tmforto-morrow;sforwas;shforshall;wdforwould;sdforshould;cdforcould;teforto the.
1st. Let the last letter of a word remain unchanged, viz.Rome, transposed,lqde.
2d. Let the first letter of a word remain unchanged, viz.Rome, transposed,rqds.
3d. Let the first and last letter remain unchanged, viz.Rome, transposed,rqde.
4th. Let the middle letter of a word of 5, 7, 9 or 11 letters remain unchanged, viz.First, transposed,xwrfo, and in words of 4, 6, 8, 10 or 12 letters, let the two middle letters remain unchanged, viz.Rome, transposed,loms.
5th. Let the first, middle, and last letters of a word remain unchanged, viz.first, transposed,fwrft.
6th. Let the middle letter of words of 5, 7, 9, 11 or 13 letters commence the word, viz.first, transposed,lxwfo.
7th. Let the two middle letters of a word of 4, 6, 8, 10 or 12 letters commence the word, viz.Rometransposed,qdls.
8th. In a word of 4, 6, 8, 10, 12 or 14 letters, let the first half of the word be substituted for the last half, viz.Rome, transposed,dslq.
9th. Let every other entire word be reversed, viz.What is the news, transposed,ntro fw ots fns&.
10th. Let every third word be reversed.
11th. Let every fourth word be reversed.
12th. Let every fifth word be reversed.
13th. Let the three middle letters of every word of 5, 7, 9, 11 or 13 letters be reversed, viz.first, transposed,xflwo.
14th. Let every word of two or three letters be prefixed to the beginning of the following word, or affixed to the end of the preceding word, viz,State of Maine, transposed,forosqx drw&s.
15th. Let one, where double letters occur in a word, be excluded, viz.willtransposed,nwv.
16th. Where two or more words, of two or three letters, follow each other, let them be joined together, viz.Cotton is on the rise, transposed,zqoq& wfq&ots lwfs.
17th. Make no separation between words of less than eight letters, viz.Cotton is on the rise, transposed,zqoq&wfq&otslwfs.
18th. Make no separation between words.
19th. Reverse the order of the letters of the whole message, viz.Cotton is on the rise, transposed and reversed,sfwl sto &q fw &qoqz.
20th. Change the key, alternately, every ten or fifteen words, using two keys.
21st. Let the two first letters of all words of four letters be affixed to the end of the preceding word, and the remaining two letters be prefixed to the word following, viz.stocks have fallen, transposed,foqzuftr gsxrvs&.
22d. Change the key irregularly, thus, for example, the first three words transpose from one key; the next three words from another key; the next three from another key, and so on.
23d. Reverse the termination of those words ending withtion,sion,ness,less,tive,ty,ly,ed, &c.
24th. Make a division of long words into two.
25th. Let those words which occur frequently and have only two or three letters remain unchanged, viz.to,a,the,of,and,for,with, &c.
26th. Let every two words, or every three, or every four, be reversed.
27th. Omit one vowel in every word.
28th. Omit the lettereat the beginning and end of a word.
29th. Omit the letterioryat the beginning and end of a word.
30th. Omit the letteroat the beginning and end of a word.
31st. In words of 4, 6, 8, 10 or 12 letters, let the first of the two middle letters commence the word, and the last of the two middle letters end the word.
32d. Lettsignifythe;eforof the;fforof;uforyou;wiforwith;iforby;ttforthat;tsforthis;frforfrom;nfornoornot;wforwill;tdforto-day;tmforto-morrow;sforwas;shforshall;wdforwould;sdforshould;cdforcould;teforto the.
We have here given a few of the various modes, by which a message can be made so complicated, that no clue will be given that shall enable the inquisitive to decypher it. Others may be easily devised, and as it is better that those using the secret alphabet should devise their own modes of transposition and reversion, none others need be given.
The following is written from the secret alphabet, and afterwards rendered more obscure by one of the methods laid down above. The key does not accompany it. Who can decypher it?
zbpvp yslup nbguxpyu zbyi, lovmy-&-yux gxp, zlegvt lovappai lubyizlvji hozovpsg zplup cbynb zbvloxbgmthejpgvizl nlep ibgm izgua zlnvlvlcutheinypvnp lhlov xmlvyloi mgua,thepnpuzvyn wmgrhzb gzhmgibpili’pvtheitjcbputhegypagvlpuiand theizlveyi byxbwj wlma yu & puzylaandiovsguyux ilymulc wlci, giowkpnzlthebvegu cymicyhzpv zbgu zbloxbz zb’ yuzpurpandiowzmp. Zlal egu’i wyayux hmypi gmluxthecyop. Lmazyep yinlufopvpa, ayizgunpyi l’ pvbvlcu,andul&g rpewmy klyuithezlvyarlup. Hgep ibgmwp byicblip ipgvnbyux eyua byixy&pu. Zlegutheslcpvzl oipthehyvpofbpg&pu,and thelmahgwmpi, cbynbyu mpxpuai voulh bgvpiyuxtheblvipiof theiou, sppeulc ulhgwmpi, iyunp, elvp cluavloihgv, bpjltpithemyxbzuyux zlbyi vgsya ngv; pgepibgmwp byi;andcbpuyu hozovp agji sbymlilsbj bpveluvepuz ibymgyzp zlzbip cblwlmapiz mgci, luth eigep zgwmpz cyzblov hvgulmyu’i ugep zbyup, elvip, yuwmgryux nbgvgnzpvi ibgmhmgep.
The following is from another key.
grvlvhmz agcxv hrvyall thezacyavzwe rexzgvlcekz, gvmarcyohc gradevn neelz; rmqcyogrvcl cycgcmgvn, grvclredt dmyokmova ndgrvcl blvxmzeylt, srlcaz, ovexvglt, xvncacyv, olmxml, rczgelt,all weregmkorgi ndmgcy,theyzmcdvnin theadcknz, bmlmueqvtheqkdoml;and theydvgbmd mgth ekgxezg. Lex grvcl zkudexv umbwa bohnvgmarvn dvmqvz hrcar xvywere togmwvks hcgrolvmg lvzsvag, ukghrcarthey were notsulxcgvnt opknov, yehvqvlt greyoi sarmyovn, ovycqz odelcozi nxmwcyo cyzvdb kynvlzgenby thexmyt;andmbgvl rmqcyo zemlvnto thevgrvlvmd lvocyzo fzacvyavinelnvl grvlvtozucivtheglqt grinrvlrcorvzg lvglvmgz,itvxsdetz, cgsehvlinmzalgmcycyothehmtumaw,tovrnlgrand inmslemarcyo odezvdtto usgrmgi txmt zrehus thelekgvit hasglmqvdvn,and thezvalvgzit hasglmqvdvn,and thezvalvgzit hasncx aeqvlvn, ukg, cbzkar isye hthemdxezg kycqvlzmd gvynvyatof therkxmy zaev yavzit wasvgvlthenczgcyagcqv armlmayvlczgcaofglkv zacvyavz amynczsvyzvwith thesvesdvas thesvesdvas thesvesdv nczsvyzvwith them; glkvgrvedeotey the aeyglmlt, rmzyvnof thesvezdvmzthesvesdv rmqvv frvl zrvokmlnz grvcl lvdcocey;andgrvcl lvdocey,incgzgklx, okmlnz rvlhe togrvx hrvy grvedeot dmyokczrvz,andnevzyeg zsvmwtogrvx;he torvlhrvgthelvdcoceyof thearklarvz yvodvag rvlandavmzvztovzgvoxrvl; hvxkzg grvyzvto it. uegrey rvlmaekygandeygrvclz, grmgzrv zsvmwzto themrvmlzthemzgkncvzinlvbvlvyavto them andwvsz grvcl zarcedz esvymz eklgvxsdvz mlv.
Another example of the manner of writing secret correspondence is here given, and for those to decypher who can.
ibeg pycydc peocyenxez yndexc tcacbp bepkpaetzo pcpcgkocevd pqzpeuw bpwuaqy iatdd pctpcawu uyyc elgcvkwl tytp wlwlxgy ppe kepcuwnc ptkeb badokecy in vkqunwac wuatza qodazw prvsaue tpeoebztqg ckphvkwv epgyecp wzqv adyge zcgtey eppd wubk prozlwy pwzopwzieydt. tytp wzqv tytp qznokw ptpcawu yclep tcbbcg epdptp tytzenncyp ywzpw lccypetglydcn ezwgo eppd igwdc czgt tbzwp lhzuczpowxck, acktepzgh tvkextpc aeptveg jezpcktncw epcgh gwvcncxc cgbtpy iatdd pvgcvcw itgzcxch qkcczn zwkkepcpwgc pzuczpowxck tzckptutzo pwcytmp, eppd ypepcb zoypdtinlceppd pypvw watbc, in tpykpeptwzpkezyvw beyawkcyzwvnczac jiyzc, in geozwp dkqwy lqphyne txnled ppkeztuyytwz cucye zoypdt wodpdk ezdpwck tquucn; jeppd etquucn lcqozwtzo pwvkextpe tzntntxqegy jawzwkpgcn pvkextpc xictyj kypytzpc.
Another plan for sending secret intelligence, is, that of using select sentences, previously agreed upon by correspondents. In this plan, the first letter of each word in the sentence, combined, is made the representative of that sentence, as in the following examples:
Another arrangement, equally adapted to the same purpose as the last, is that of taking the first letter of the sentences, then arranging them in alphabetical order, and numbering them, thus:
These two systems have been found to answer in practice, and were much used in telegraphic business during the last session of Congress.
[From Silliman’s Journal.]
Art. XVI.Experiments made with one hundred pairs of Grove’s battery, passing through one hundred and sixty miles of insulated wire; in a letter from Prof. S. F. B. Morse, to the Editors, dated New York, Sept. 4th, 1843.
Dear Sirs—On the 8th of August, having completed my preparations of 160 miles of copper wire for the Electro Magnetic Telegraph, which I am constructing for the government, I invited several scientific friends to witness some experiments in verification of the law of Lenz, of the action of galvanic electricity through wires of great lengths. I put in action a cup battery of one hundred pairs, which I had constructed, based on the excellent plan of Prof. Grove, but with some modifications of my own, economising the platinum. The wire was reeled upon eighty reels, containing two miles upon each reel, so that any length, from two to one hundred and sixty miles, could be made at pleasure to constitute the circuit. My first trial of the battery was through the entire length of 160 miles, making of course a circuit of 80 miles, and the magnetism induced in my electro magnet,[10]which formed a part of the circuit, was sufficient to move with great strength, my telegraphic lever. Even forty-eight cups produced action in the lever, but not so promptly or surely.
We then commenced a series of experiments upon decomposition, at various distances. The battery alone (100 pairs) gave, in the measuring gauge in one minute, 5.20 inches of gas. When four miles of wire were interposed, the result was 1.20 inches; ten miles of wire, .57; 20 miles, .30 inches; 50 miles, .094. The results obtained from a battery of 100 pairs are projected in the following curve: