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strand coated with tar, pitch, and India rubber, negative currents are transmitted many times from Governor's island to the Battery in New more rapidly than successive impulses of the York, and the next morning was beginning to same character. After being laid, the wires receive communications through it, when the were first worked by the Ruhmkorff induction wire was caught in the anchor of a vessel get- coils and a Smee's battery, and afterward with ting under weigh, and being hauled on board a Daniell battery; but the current was for the was robbed of a considerable portion which most part so weak as scarcely to work the the sailors carried away. It was to avoid the most delicate relay, susceptible to an impulse risk of disturbance that Prof. Morse entered that can hardly be perceived on the tongue. upon those investigations which led to his dis- The effect was indicated at the Newfoundland covery of a method of transmitting the current station by the deflection of a delicate galvanomacross a body of water by means of extending eter, and at Valentia in Ireland by that of the the wires a distance proportionate to the width reflecting galvanometer of Prof. William Thomalong the banks on each side, and causing the son, the effect of which is to multiply the movepoles to terminate each pair opposite each other ment in a ray of light reflected from a mirror atin large metallic plates in the water. Mr. tached to a very delicate magnetic needle. This Samuel Colt laid a submarine cable in 1843 ray being thrown upon a surface at some disfrom Coney island and Fire island, at the tance, a movement of the needle, that is othermouth of New York harbor, up to the city, wise imperceptible, may be even measured upon and operated it successfully. (See Colt, Sam- a graduated scale. The transmitted current UEL.) The first submarine telegraph wire laid was, much of the time that the cable continued in Europe was across the Rhine from Deutz to in action, so weak that every expedient of this Cologne, a distance of only about half a mile; kind was necessary to render the signals per. it was insulated with gutta percha, and laid by ceptible. From the first there appears to have Lieut. Siemens of the royal Prussian artillery, been a defect in the part of the cable laid toThis appears to have been the first application of ward the Irish shore, and this caused a temgutta percha to this purpose, the substance about porary interruption of the communications that that time first beginning to attract attention. passed between the ships, and excited much The grand attempts to connect the European fear for the result of the enterprise until these with the American continent by laying a cable were soon renewed; and it is generally believacross the Atlantic, commenced in 1857 and ed that the very imperfect signals and variable perfected Aug. 5, 1858, have been noticed in conditions of the cable during the time that the article FIELD, Cyrus W. Before these were signals passed through it from Aug. 13 to Sept. undertaken great encouragement was given to 1 were attributable to this original defect, at the enterprise by the successful experiments least as the main cause. During this time 129 made on Oct. 9, 1856, in transmitting distinct messages were sent from Valentia to Newsignals at the rate of 210, 241, and even 270 per foundland, and 271 from Aug. 10 in the other minute through a number of connected coils of direction. The number of words in the former wires insulated with gutta percha, and making direction were 1,474, and in the latter 2,885. a total length of about 2,000 m., increased to a The message from Queen Victoria to the presivirtual circuit of 2,300 m. by the interposition dent of the United States, consisting of 99 of fine wires at the joinings of the coils. The words, occupied in its receipt at Newfoundland wires were excited through the magneto-electric 67 minutes. The rate of reception of messages coils of Mr. Whitehouse, and the signals were at the two stations was however very variable, received upon the ordinary recording apparatus the signals being often unintelligible and reof Prof. Morse. But a great difference was quiring several repetitions. The retardation afterward experienced in the working of the consequent upon the phenomena of induction, wires when submerged. Before the laying of incident to the wire assuming the character of the cable it was ascertained that insulated wires a Leyden jar, was considered by W. T. Henley, acquire a new character when submerged, and telegraph engineer, of London, so great that in instead of transmitting the current as simple the most perfect cable across the Atlantic no conductors, they are of the nature of the Ley- more than 4 words per minute under the most den jar, the gutta percha corresponding to the favorable circumstances could be transmitted glass, the inner wire to the interior coating, and on the plan of the dots and lines; but if a letthe iron coating or the fluid surrounding the ter could be indicated by one or two signals, cable to the exterior conducting surface, and the rate of course would be proportionally inthat consequently the cable must be charged creased. The feebleness of the current through throughout the entire length before any ef- the cable in consequence of any defect rendered fect is produced. Among other interesting phe- its working liable to be interrupted by the natnomena, it was observed that the voltaic current ural currents of electricity in the earth, which is not transmitted so rapidly through such a by induction excite in an insulated wire curconductor as the magneto-electric current; that rents moving in a contrary direction to their several distinct impulses may pass in succes- own, and overcome any artificial electricity of sion at the same time, one after the other, little force in the conductor. The changes in through the wire within certain limits without the natural currents from positive to negative interference; and that alternating positive and and back again may be often mistaken for those

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transmitted from the opposite station. With bay on the Atlantic side were recovered in perfect insulation the natural currents would 1860, and in the short time that it had been in general be overcome by the greater power submerged the iron covering was found to be of the battery. On the failure of the cable to much eaten by rust, so as sometimes to fall off communicate intelligible signals, every effort as the cable was hauled in. In those parts was made to ascertain the exact cause with a that were wrapped with tarred yarn the iron view of remedying the defect if possible. The wires were preserved bright and free from most able electricians were sent to Valentia, rust. The gutta percha and copper wires and the most powerful batteries, as well as the seemed to be in as good condition as when the great magneto-electric machine of Mr. Henley, cable was laid. The cost of the Atlantic cable were applied to test the condition of the cable. was as follows: for 2,500 m. at $485 per mile, On Oct. 20, in the course of these trials, a com- $1,212,500; for 10 m. at $1,250 per mile, $12,munication was received at Valentia and im- 500; and for 25 m. shore ends at the same perfectly read as follows: "Two hundred and price, $31,250 ; making altogether $1,256,250. forty t- k- Daniells now in circuit.” The expenditures of the company up to Deo. These were the last intelligible signals trans- 1, 1858, had amounted to $1,834,500.-After mitted through the wires, and it afterward ap- the failure of this great enterprise the attention peared that the full message was: “Two hun- of some telegraphers was directed to the pracdred and forty trays and seventy-two liquid ticability of extending a cable across the AtDaniells now in circuit.” The power thus em- lantic from Labrador to Scotland, by way of ployed was more than 1,000 times what would Greenland, Iceland, and the Faröe islands. The be required in an ordinarily well insulated con- route is about 1,800 m. long, and would present ductor to give perfect signals to the mirror gal- no continuous length of submarine cable for a vanometer; and the hopelessness of further greater distance than that between Labrador attempts to transmit through the cable was and Greenland, which is about 600 m. Mr. T. apparent unless the faulty points could be re- P. Shaffner, of the United States, had obtained paired. The report of Mr. Henley of Sept. 30, in 1854 from the king of Denmark a concession 1858, to the directors of the Atlantic tele- of exclusive rights in Greenland, Iceland, and graph company, is full of interesting infor- the Faröe islands for this purpose. Failing to mation as to the methods employed and the interest the government of the United States, principles involved in these experiments. To Mr. Shaffner_chartered a vessel and sailed the end of the cable a voltaic battery was con- from Boston, Aug. 29, 1859, to make the prenected by one of its poles, a galvanometer was liminary surveys at his own expense. After his placed in the circuit, and the other pole was arrival in Glasgow, Scotland, the project was connected with the earth. The current being brought before the British government, and in then transmitted, the resistance it meets is in- June, 1860, a steamer of the royal navy was dicated by the deflection of the galvanometer. despatched to take the deep sea soundings, and The comparative resistance of the cable and a private steam yacht was also sent to examine that of a given fine copper wire being known, the landing places for the cables and the prowhich for one of No. 40 gauge may be as 175 posed overland routes. Mr. Shaffner with this to 1, and the degrees of deflection caused by expedition again visited the islands and the inthe cable being accurately read, with bat- terior of Greenland, and it is said that a report teries of different degrees of strength, the pro- favorable to the route was carried back to Engcesses are repeated with coils of fine wire, the land. No further steps however have yet been length of which is added to or diminished until taken for establishing this line, and the prosthe readings of the galvanometer exactly coin- pects of its being constructed are not encourcide in every case with those noted when it aging. The failure of a number of submarino was connected with the cable. The length of lines, some of which are named below, causes the fine wire will then give that of the cable great distrust as to the practicability of keepto the extreme end of the circuit, or to the ing up a telegraphic communication across the point where the battery current leaves it to Atlantic with the knowledge and resources at return through the earth. By this method present available; and the whole subject was chiefly the electricians came to the conclusion generally regarded as abandoned, when, in Feb. that the fault in the cable was about 279 m., 1862, Mr. Cyrus W. Field again visited London or not more than 300 m., from Valentia ; and with the view of carrying out the original enthey also inferred that the wire was not sepa- terprise. He there received from Messrs. Glass, rated, inasmuch as obscure signals were re- Elliot, and co., manufacturers of most of the ceived through it from the other station. This, submarine cables that have been made, favorand the establishment of a current through able propositions for furnishing and laying a the wire and back by the earth, also proved good and durable cable, in the practicability of that the copper wire could not at the faulty which they showed their confidence by offering place have come in contact with the iron cov- to share the risk. The cable which they laid ering of the cable. The impossibility of rais- for the French government between France ing the cable from deep water without break- and Algeria, 520 m. in length, they state, is in ing it rendered any attempt to remedy the de- perfect and successful working order, under fect hopeless. Portions of the cable in Trinity water as deep as any between Newfoundland

Date when laid.

Conductors.

From

То

Size of O. P. per Bir-
mingham wire gauge.

No.
Size.

1854 Sweden

Denmark
16 No. 2 10

12
13541 Italy.
Corsica

1 12 1 110 660 1854 Corsica..

Sardinia...

16 1 12 1 10 1853 Egypt

16 2 101 1 10 1856 Newfoundland. Cane Breton

1 12 9 85 1856 P. Edward's island. Sew Brunswick

1 12 9 12 1837/ Norway, across .... Fiords..

1 10 6 49 1857 | Across mouths of.. Danube.

129 3 1858 England.

Holland

13 0 10.00 183. England. Hanover

3 12 641 290 1858 Norway, across.. Fiords ..

1 10 6 16 1859 Alexandria.

3 10 1 2 1859 England. Dcomark

3 12 54350 1,050 1859 Sweden Gottland

1 12 9 64 64 1850 Folkstone Boulogne.

3 12 0 24 1,44 1859 Liverpool.

Holyhead 2 16 3 12 6 25 50 1939 Across rivers. In India..

13 0 9 2 10 1859 Malta Sicily...

1 10 5% 60 1859 England.

Isle of Man

16 2 10 64 1560 Jersey Pirou, France..

12 5% 21 166 France. Algiers

0 10 141 520 1860 Corfu Otranto..

0 10 5% 80 1861 Toulon. Corsica

0

10 141 60 1861 Valta Alexandria

1,518 1,518

Outside wires.
Length of cable in

statute miles.
Length of Insulated

Size.
8888:87 Sasw=2*3$$wire in statuto miles.

Total...

3,497 5,702

• Strand,

Steel covered with hemp.

and Ireland; and they refer to the following the cable had been made for this purpose at & list of cables manufactured and laid down by cost of £400,000. All these failures are exthem, all of which, except three short lines, plained chiefly through the neglect of the parbroken by ships' anchors, are in successful ties employed in laying the cables, and in no operation:

case through insuperable natural obstacles. The Atlantic cable was no doubt originally defective, and was injured beside, first in the way in which it was exposed to the sun, and afterward in the handling, and finally in the laying. Its weight was about 19 cwt. per mile. Some of the earlier cables were much heavier-even 7 tons per mile. For cables to lie in deep water, whero no disturbance from anchors, cur

rents, or drifting materials is likely to reach 40 them, great weight beyond that required to

sink them is considered of no especial advan

tage, and the heavy iron coating is found to be 1.80 5.00 altogether useless; but near the shore cables

of greater strength and weight are required to withstand the disturbing causes to which they are exposed. The principles of the electric

telegraph are treated in many of the works on o electricity, and the ablest papers upon this subNject by the most eminent electricians are found

in the volumes of the transactions of the scien

tific societies of Europe. Of the works spein. 118 11

cially devoted to this subject may be named “The Electro-Magnetic Telegraph, with Reports

to Congress," by A. Vail (Philadelphia, 1845); The line from Malta to Alexandria is laid in sec- “ The Electric Telegraph, its History and Progtions by direction of the British government; the ress," by Edward Highton, O. E., a number manufacturers would have preferred to make of Weale's series (London, 1852); “Historical it a single continuous line. The gutta percha Sketch of the Electric Telegraph,” by A. Jones company of London also express full confidence (New York, 1852); "The Electro-Magnetic Telin the successful working, and their readiness egraph," by L. Turnbull (Philadelphia, 1853); to guarantee this, of one of their manufacture. " The Telegraph Manual,” by Tal. P. Shaffner England is connected with the continent by 7 (New York, 1859); and “ History, Theory, and submarine cables. The line from Dover to Practice of the Electric Telegraph," by George Ostend, laid in 1852, is 75 m. long, and contains B. Prescott (Boston, 59). 6 wires. The lines laid in the Black sea in TELEKY, or TELEKI, László, count, a Hun1855, for communication between the Crimea garian patriot, born in Pesth, Feb. 11, 1811, and Constantinople, were in two sections, one died there in the night of May 7–8, 1861. Befrom Constantinople to Varna, 200 m. long, longing to a family distinguished by its possesand one from Varna to Balaklava, 150 m. sions and connections in Hungary and TranThese contained but one wire each. Their cost sylvania, as well as by political and literary when laid was £22,000, and they worked with merits, he early prepared himself for a political complete success. In 1857 a line was laid, at a career, studying at Pesth and Patak, gained a total cost of £125,000, from Malta to Corfu in reputation for rare attainments, contributed to the Mediterranean, on which 400 m. of cable political and miscellaneous periodicals, and in similar to that adopted for the Atlantic route 1837 was elected a corresponding member of the was paid out. This is reported to have failed. Hungarian academy, of which his half brother The Dutch laid down a cable in 1861 between Count Joseph Teleky (born 1790, died 1855), Batavia and Singapore, a distance of 660 m.; the author of the great history of “The Age of and after conveying a few messages it was the Hunyadys," was the president. In 1842 he several times broken by anchors or coral reefs, published his Kegyencz ("Favorite"), a drama, and was finally abandoned. The English govo which has since successfully maintained itself ernment a few years since attempted the es- on the stage. Having been for some years a tablishment of a line through the Red sea to member of the diet of Transylvania, he in 1843 connect the telegraphs in India with those took his seat in the upper house of that of of the Mediterranean. This prored entirely Presburg, where he soon became prominent unsuccessful, never conveying even a single for his eloquence, boldness, decided opposition message throughout, and the project was aban- to the rule of Metternich, and a consistent addoned, although the government had given vocacy of liberal reforms. He subsequently a guarantee of 4 per cent. on £1,000,000 for became president of the “Opposition Club" at half a century. A project to connect Falmouth Pesth; and on the advent of his party to power in England with Gibraltar was abandoned after in 1848 he was elected to the reorganized house

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of representatives, in which he sided with the then set out to seek information of his long radicals. In Sept. 1848, he was sent as envoy absent parent. Accompanied by Minerva, who of the Hungarian government to Paris, where had assumed the appearance of Mentor, a faithhe published Le bon droit de la Hongrie (1849), ful friend of his father, he visited Pylos and Sparand zealously but vainly strove to gain the rec- ta, and was hospitably received by Nestor and ognition by the French government of the in- Menelaus. From Sparta Telemachus returned dependence of Hungary, on its proclamation at home, and on his arrival found his father with Debreczin. After the close of the Hungarian the swineherd Eumæus, disguised as a beggar. war, residing alternately in Paris, Brussels, Their mutual recognition followed immediateand Geneva, he continued active in rousing ly, the suitors were slain or driven out, and Tethe sympathies of the western nations for the lemachus accompanied his father to the aged cause of his country by contributions to the Laërtes. He is called by different authors the press, and in securing by personal representa- father of Latinus, and the founder of the town tions the moral support of men of high stand- of Clusium in Etruria. ing. He gained easy access to the French TELEOSAURUS, a genus of fossil crocodilcourt, during the war of 1859 was a member ians of the secondary epoch established by of the Hungarian national committee in Italy, Geoffroy, differing from the living crocodiles in and toward the close of the following year having biconcave vertebræ. The general form secretly repaired to Dresden. Here he was of the cranium was that of the gavials; the arrested by the Saxon police, and surrendered nostrils opened anteriorly at the end of the to the Austrian government, who 10 years be- muzzle and posteriorly on a level with the jufore had sentenced him to death. The changed gal arch; the lower jaw was spoon-shaped at condition of affairs in that empire, however, the end, with teeth on the sides like canines, made the execution of the sentence a political the other teeth being small, equal, conical, and impossibility, and the emperor Francis Joseph, adapted for seizing a fish prey; the body was in a personal interview with the prisoner (Dec. protected by larger and more solid plates, the 31, 1860), restored him to liberty on the promise anterior limbs were smaller, and the posterior of severing his connection with the Hungarian more fin-like than in the present crocodilians. refugees and of abstaining for a time from po- The strata which enclose their remains indicate litical agitation. The returned exile was re- & marine habitat, and their habits were probceived by his countrymen with the liveliest ably those of the gavials. The genus has been demonstrations, and was soon elected by his divided by modern paleontologists into several former constituents to the newly convoked subgenera, as given by Pictet. In the lias is house of representatives. The diet was opened found mystriosaurus (Kaup), having a very April 6, 1861, and the leader of the more mod- long muzzle, flattened head, and eyes directed erate supporters of the laws of 1848, Francis upward. The T. (M.) Chapmanni (König), Deák, prepared an address to the monarch, on from the upper lias of Yorkshire, England, is which the debates were to open on May 8. described in the “Philosophical Transactions Teleky, the leader of the radicals, who opposed of 1758; the vertebræ were 64, 16 being dorsal, any measure looking like a recognition of and the teeth about 70 in each jaw; some of Francis Joseph as king of Hungary, and any the dermal plates were 3] inches in their transadvances on the part of the house toward a verse diameter; it attained a length of about compromise, prepared an elaborate and states- 13 feet. Macrospondylus (H. de Meyer) had manlike discourse on the situation, in opposition longer vertebræ and the S-shaped femur not to the address. This discourse was found on longer than the leg; pelagosaurus (Bronn) had his desk, on the morning of the 8th, and near the eyes more widely separated, a shorter symit on the floor the dead body of the writer, physis of the lower jaw, and the anterior limbs pierced by a pistol ball. Doubts on the ex- relatively small. The name has been generally pediency of his almost revolutionary policy, restricted to the species found in the oolite, scruples concerning his word of honor pledged especially the T. Cadomensis (Et. Geoffr.), or to the emperor, and bodily suffering are be- crocodile of Caen, from the limestone of Norlieved to have induced him to commit suicide. mandy. This is characterized by large orbits When the president of the house announced near together, a flattened muzzle 5 times as the catastrophe, several of its members burst long as wide, very long transverse processes of into tears and the session was suspended. The the dorsal vertebræ, and thick rectangular debate on the address was commenced later, scales forming 10 regular series, each containand after a protracted contest Deák's propo- ing 15 or 16; it must have attained a length sition was carried.

of 20 feet. Other genera are glaphyorhynchus, TELEMACHUS, a Greek prince of the heroic æolodon, and gnathosaurus of H. de Meyer. age, the son of Ulysses and Penelope. When The T. longirostris (Ét. Geoffr.) was found in Ulysses went to Troy, Telemachus was an in- the kimmeridge strata of Havre and Honfleur, fant, and in his father's absence he grew nearly and described by Cuvier in his Ossemens fossiles. to manhood. About the time that the gods TELESCOPĚ (Gr. ende, far, and oKoTew, to had decreed the father's return home the son view), an optical instrument designed to aid made an unsuccessful endeavor to eject the the eye in viewing distant objects, causing troublesome suitors for his mother's hand, and them to appear magnified by enlarging the

angle under which they are seen, and at the individuals, Hans Lippersheim, a spectacle same time increasing their brightness by col- maker in Middelburg, and Jacob Adriansz, lecting into the eye a greater number of rays called also Metius, a native of Alkmaar. The than would naturally enter it. To this instru- former of these, on Oct. 22, 1608, presented to ment we are indebted for almost every item of his government three instruments with which our knowledge respecting the physical appear. “one could see things at a distance," applying ance of the heavenly bodies, while to the navi- at the same time for a "protection" or other gator, the explorer, and the engineer, it is a pow- equivalent for a patent. Metius made a similar erful and often indispensable auxiliary, either present and a similar application later in the as an instrument of research or when adapted same month, but said that he had manufactured to instruments of observation.—The general such instruments two years before. It has construction of the telescope is based upon the been frequently stated that Zacharias Jansen well known property possessed by a convex lens also invented the telescope more than a year or concave mirror, of converging to a focus the later; but the evidence adduced only proves, rays of light falling upon it from any object, and according to Olbers, that he made telescopes of forming at that focus an image of the object which may have been imitated from those of itself. This image may be rendered visible, as Lippersheim; and this is the more likely as in the camera obscura, by interposing at the both were spectacle makers in the same city, focus a white screen, a plate of ground glass, and it is hardly possible that the public transor, still more strikingly, a cloud of light smoke action with the latter could have escaped the within which the image will appear suspended. knowledge of Jansen. The attempt was made But if the rays be allowed to proceed without by the states-general, it is said, to retain to interruption, and the eye be placed in the axis themselves the knowledge of this invention, of the lens or mirror and at the proper distance whose importance in war was at once perceived from the focus, the image will be seen more dis- by Prince Maurice; but it is also said and be tinctly than before; and if the focus be nearer lieved that the French ambassador soon sucto the eye than to the lens, the apparent di- ceeded in obtaining from them an order for mensions of the image will be greater than the two telescopes for his own government. It is apparent dimensions of the object itself. This is certain that the report of the invention soon the simplest, though not the common form of spread abroad, and the new and wonderful inthe telescope. Usually a second lens, of shorter struments found their way to London, Paris, focus than the first, is introduced near the im- and even Venice. But by no person in any age, the effect of which is to increase still fur- city was the idea more eagerly welcomed, or ther the apparent magnitude of the object; its great importance more quickly recognized, and thus is constituted the ordinary telescope, than by Galileo, then visiting at the last named which, in its elementary construction, consists place. He was evidently willing, at a later of an object glass” or “object mirror," of as day, to be thought the second inventor, guided large dimensions as practicable, and an "eye only by an uncertain rumor; but it is reported lens," which enables the eye to receive the im- by some that he actually saw one of the Dutch age under the greatest practicable angle. The telescopes, and Huyghens, referring to the object glass is always necessarily convex, and matter, declared that the man who could inthe mirror concave, but the eye glass may be vent the telescope unguided by chance would either; if convex, it is placed at the proper be more than mortal. Whether seeing the indistance beyond the focus, and, the rays hav- strument or not, however, his sagacious intel. ing crossed, the image then appears inverted; lect fully appreciated the great scientific value if concave, as in the common opera glass, it is of the invention; and returning to Padua with placed within the focus, and objects appear in some lenses, he immediately began to improve their natural position. The magnifying power upon what he had seen, if not to experiment of the instrument is measured by dividing the independently, under guidance of the mere refocal distance of the object glass by that of the port, and he soon found a better and more cereye piece; the illuminating power depends tain result than had been chanced upon by the mainly on the size of the object glass.-English original inventor. He made a leaden tube, and writers are fond of alleging that the telescope fitted at one extremity a plano-convex lens for was certainly known to Roger Bacon and used object glass, and at the other a suitable planoby Digges before the 17th century, but the first concave for eye piece. This, his first telescope, really definite accounts of the invention date magnified only three times; he then made anfrom the latter part of the year 1608. Magnify- other of more than double this power, and soon ing lenses had long been known, and even the after, with a magnifying power of 30, the “Tuscompound microscope had been invented by the can artist” betook himself to the study of the Jansens nearly 20 years before this date—a dis- heavens, where his first discoveries excited covery which has somewhat embarrassed the more wonder than that of the “optic glass” itstudy of the question before us from confusion self. The popular curiosity excited by both was of the by no means explicit terms with which so great, as he himself tells us, that he was both instruments are described. But it is now compelled night after night, though wearied, to generally conceded that the honor of having stand by his glass to show_its wonderful permade the first telescope belongs to one of two formances to the curious. But we can scarcely

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