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Imperfect. Tuviéra, tendría, or tuviese, I would, should, oi might have.

Tuvieras, tendrías, or tuvieses, thou wouldst, should8t, or mightst have.

Tuviéra, tendría, or tuviese, he would, should, or might have.

Tuviéramos, tendríamos, or tuviésemos, we would, should or might have.

Tuvierais, tendríais, or tuvieseis, you would, should, or might have.

Tuvieran, tendrían, or tuviesen, they would, Bhould, or might have.

First Future.

Si tuviére, if I should have.

Si tuviére», if thou ihouldct have.

Si tuviére, if he should have.

Si tuviéremos, if we should have.

Si tuviereis, if you should have.

Si tuvieren, if they should have.

Pluperfect.

Hubi&a, habría, or hubiese tenido, I would, should, or might have had.

Hubieras, habrías, or hubieses tenido, thou wouldst, shouldst, or mightst have had.

Hubiera, habría, or hubiese tenido, he would, should, or might have had.

Hubiéramos, habríamos, or hubiésemos tenido, we would, should, or might have had.

Hubierais, habríais, or hubieseis tenido, you would, should, or might have had.

Hubieran, habrían, or hubiesen tenido, they would, should, or might have had.

Second Future. Si hubiere tenido, if I should

have had. Si hubieres tenido, if thou

shouldst have had. Si hubiere tenido, if he should

have had. Si hubiéremos tenido, if we

should have had. Si hubiereis tenido, if you

should have had. Si hubieren tenido, if they

should have had.

In ordinary conversation, instead of the second person singular and plural,, vmd. with the third person singular, and vmds. with the third person plural of the verb, are used; as,

Vmd. es, you are. | Vmd. ha tenido, you have had.

Vmds, son, you axe. | Vmds. han tenido, you have had.

The pronoun You in English is used in both numbers and both genders without any change: in Spanish, vmd. (usted) Tata its plural vmds. (ustedes), but does not undergo any change to distinguish the gender to which it may be applied. Thus, What do you say, sir i ;qué dice vmd., señor? What do you say, madam? ¿ qué dios vmd., señora? "What do you say, gentlemen? iquédicen vmds., señores) What do you say, ladies? i qué dicen vmds., señoras i

The phrases " to be hungry," " to be thirsty," " to be afraid," 4,to be eold," "to be hot," are rendered in Spanish by the verb tetter (to have), and the corresponding noun; as "to have hunger," " to have thirst," "to have fear," " to have shame," "to have cold," "to have heat."

Vocabulary.

Manzana, apple. Pera, pear.

Nuez, nut. Bota, boot.

Sopa, soup. Aceite, oil.

Calentura, fever. Memoria, memory.

Marmol, marble. Hierro, iron.

Taeiéncia, patience. Suceso, success.

Calor, heat. Frio, cold, coldness.

Vergüenza, shame. Temor, fear.

Silla, chair. -Ayer, yesterday.

Es estraño, it-is strange. Con, with.

Model Sentences.

Juan tiene calor, John has heat not (t. e. John is hot), not Tenga Pedro dinero, let Peter ashamed). have money.

Spanish-english.

i Tiene vmd. manzanas? Tengo manzanas. Tenemos plumas. Tienen peras. Vms. tienen sillas. Ella tiene hambre. Tengo sed. Tenemos calor. Tienen vergüenza. Tengo temor. Tenemos frío, i Tengo yo vergüenza? Tienes ver

that

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güenza. Tenéis una lampara. ¿ Quién tiene nueces? i Quienes tienen peras? Mis hermanos tienen hierro. Tengo manteca. Tenéis espejos. Tenemos tenedores. Tienes cuchillos. ¿Qué especie de botones tiene V. í i Tenemos marmol? j Qué especie de azúcar tiene el aldeano? Ella no tiene marido. Tengo tres hijos y dos hijas. Tenéis tres hermanos. Tenemos una casa. <Tenemos médias? «Tienes candeleras? Non tengo harina. No tenéis leche. La rosa tiene espinas. Ymd. tiene memoria. María tiene mucha confianza en el juez. «Tienen vms. sopa? Tenemos suceso. ¿ Tenéis paciencia? El médico tenía confianza en la Española. Ella no tenia lampara. Teníamos hambre. Yo tenia una rosa. Tenían dinero. Ymd. tenia i Vms. tenían confianza en mi tenía prudencia. «Tenia yo zapatos i ¿Teníamos botas? t No tenían mesas?

Tuvo azúcar ayer. Tuvieron manteca ayer. Tuve botones ayer. Ella tuvo harina ayer. Tuvisteis dinero. Tuvimos lámparas. Tuviste candeleras. No tuvieron espejos. i Tuviste una pluma? Tuve una casa. Tuvimos medias de ayer. Tuvo sillas ayer.

El zapatero ha tenido mucho cuidado. He tenido i hierro. Has tenido tres hijas. Hemos tenido dos hiji María ha tenido calentura. Ella has tenido dos Han tenido muchos cirid Yo no había tenido sopa.

Tendré una candelera, aceite. Vmd. tendrá hambre. Tendrás calor. Tendremos sed. Tendrán vergüenza. Tendréis temor. Tendré frío. Habré tenido dinero.

Tened paz con todos los hombres. Ten paz co hijos del médico. Tenga plumas. Tengan miel, espejos. Tenga vmd. confianza en él.

Quiero que mi madre tenga harina, aceite. Probable es que tengan lamparas. * Quiero que Haría tenga dinero. Quiero que yo tenga medias de seda. Probable es que tengamos algún mérito. Es posible que tengáis hambre. Quiero que vms. tengan candeleras.

No era estraño que tuviesen peras. No era estraño que yo tuviese dinero. No era estraño que vmd. tuviese aceite. Era preciso que no tuviésemos azúcar. Si tuvieses botas, yo tendría zapatos. Juan tendría un tenedor. No creo que Pedro haya tenido manteca. ¡ Ojala yo no hubiera tenido estas lamparas! ¡ Ojala no hubieran tenido esos libros! Si yo tuviere paciéncia, tendré suceso. Si mis hijos tuvieren paciéncia, tendrán suceso.

English-spanish.

They-have pears. Have you («ni?.) apples? I-have apples. We-have pens. They-have pears. You (vms.) have chairs. She is hungry. I am thirsty. We are hot. They are ashamed. I am afraid. We are cold. I am ashamed. Thou art ashamed. Ye have a lamp. Who has nuts? Who have pears? My brothers have iron. I have butter. Ye have looking-glasses. We have forks. Thou hast knives. What Bort ofbuttons have you (vmd.)? Have-we marble? What sort of sugar has the villager? She has no husband. I have three sons and two daughters. Ye have three brothers. We have a house. Have we stockings t Hast thou candlesticks? I have no flour. Ye have no milk. The rose has thorns. You (vmd.) have a memory. Mary has much confidence in the judge. Have you (vms.) soup i We have success. Have ye patience?

The physician had (imperf) confidence in the Spanishwoman. She had (imperf.) no lamp. We were (imperf.) hungry. You (vms.) had (imperf.) confidence in my brother. Had (imperf.) we boots?

He had sugar yesterday. They had butter yesterday. I had|buttons yesterday. We had a fever yesterday. Ye had chairs yesterday.

The shoemaker has had much care. I have had much iron. Thou hast had three daughters. We have had two sons. Mary has had a fever. She has had-two husbands. They have had many cares. Ye have had much money. I had not had soup.

I shall have a candlestick. She will have a fork. Theywill have oil. You (vmd.) will be hungry. Thou-wilt-be not We shall-b? thiraty. They will be ashamed. Ye will be afraid. I shall be cold. I will have had money.

Have-ye peace with all men. Have-thou peace with all the son* of the physician. Let-him-have pen*. Let-themhave honey. Let-us-have looking-glasses. May you (vmd.) cave confidence in him.

I wish that my mother may-hare flour. It-is possible that thou-mayest-have oil. It-is probable that they-may-have lamps. I-wish that Mary may-have money. I-wish that I may-have silk stocking!. It-is probable that we-may have some merit. It-is possible that ye-may be hungry. I wish that you (tmi.) may-have candlesticks.

It-was (era) not strange that they-ahould-have pears. Itwas not strange that I should have money. It-was not strange that you (vmd.) should have oil. It was necessary that we should not have sugar. If thou ahouldst have boots, I would have shoes. John would have a fork. I do not believe that Peter has (say, may-have) had butter. O-that I had not had these lamps! O-that they-had not had those books! If I have (say, shall have) patience, I shall have success. If my sons have (say, shall have) patience, they will have success.

The student can now write all the persons of the tenses of the verb tener, as he has been already directed with regard to previous verbs.

OF THE CONJUGATIONS OP REGULAR VERB*.

It has been already mentioned that there are in Spanish three conjugations: the first comprehending verbs whose infinite ends in or; the second, those ending in er; and the third, those ending in tr.

Every verb consists of two parts—the root and the termination, or the verb-root and the verb-ending. The verb-root consists of those letters which are not changed by inflection; as am in am-dr, am-o, am-aba, am-d, am-ard. Those letters, which may be changed by inflection, to show the different moods, tenses, persona, and numbers, constitute the verb-endings. Thus, in the preceding examples, the letters or, o, iAa, i, are, are the verb-endings.

The following is a tabular view of the verb-endings of all the conjugations. The figures 1, 2, 3, denote the first, second, and third conjuga'

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I conjugations respectively:—

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A change takes place in the first letter of the verb-ending in the gerund, third person singular and plural of the perfect definite in the indicative, and in all the persons of the first and third forms of the imperfect subjunctive, and in the first future of the same mood, in the second or third conjugation, when the verb-root ends in a, e, or u. This change is merely the substitution of y for »; as, ea-dr, ca-ydndo, ea-yb, ea-ydron, ca-yere, ea-ydse, etc.; cre-dr, cre-ydndo, cre-y6, cre-yeron, ereydre, ere-ydre*, etc.; argi-ir, argu-ydndo, argu-yb, etc.

If the last letter of the verb-root be a silent u, the change in

CHANGES IN THE VERB-SOOT.

In order that the last letter of the verb-root may retain, in all the tenses, the same sound which it has in the infinitive, a change of letters is sometimes required. This change can only take place when the verb-root end in e, g, gu, or qu.

In inch cases, there is changed, in thejirrt oonjugatkm, • of the verb-root into qu before t of the verb-ending; at,

g of the verb-root into gu before < of the verb-ending; as, pdg-ar; pdgu-ts. In the second conjugation, e of the verb-root into s before a or o; as, venc-er; vdnt-at, vdnz-o.

g into j before o or o; as, converg-er; eonvdrj-a, eonvdrj-o.

In the third conjugation, e of the verb-root into z before a or o; as, un-dr; inz-as, unz-o. f „ „ j a or o; as, ung-ir; iinj-a, unj-o.

gu into g before >oro; as, consegu-ir; cotuig-an, contig-o. qu into c before a or o; as, delinqu-ir; delinc-as, delinc-o.

The reason for these changes will at once be perceived by the student on his referring to what we have said on the "Sound of the Consonants:" thus e is sounded like k before a or «, and like th before e or i; while qu before e or i has the sound of k. If, then, in conjugating toedr (in the present tense of the subjunctive mood, for example), we retain the e in the verb-root, the pronunciation would be altered from the sound of k to that of th; thus, to-cdr, pronounced to-kdr, and tb-ce pronounced to-thay. But by changing c into qu, the hard sound of * is retained; thus, tb-qut, pronounced tb-kay. And so before a or o, by changing e, g, gu, and qu of the verb-root of the second and third conjugations into z, j, g, and c respectively; and g of the first conjugation into gu before e of the verb-ending.

The compound tenses are always formed by the different persons of the verb haber and the paBt participle of the verb to be conjugated.

The compound tense* are the past infinitive, the gerund of the past, the perfect indefinite, the first pluperfect, the second pluperfect, and second future of the indicative; the perfect indefinite, pluperfect, and second future of the subjunctive. If the student has committed to memory the simple tenses of the verb hater, he is able to conjugate the compound tenses of any verb in Spanish.

FRENCH READINGS.—No. XXXHI.
EUDOXIE.
Section III.

C'est juste!' répliqua Eudoxie, en rougissant pour sa sœur de cette interprétation; mais, ajouta-t-elle, tu vas* donc me laisser seule, chargée d'une si grande responsabilité ?*....

—Ah! répondit Thécla, je tomberais bientôt malade d'ennui, et je serais pour toi-même une chargeb plutôt qu'une aide.3 Les caractères et les tempéraments varient comme les figures.1 Tu te plais à cette vie d'abnégation auprès de ce bon vieillard;5 je t'admire et je voudrais' t'uni

ter; mais je n'en ai ni la force ni le courage Une

langueur mortelle m'a saisie .... l'air de la cour me ranimera.

Adieu donc, Thécla, reprit Eudoxie, adieu, et sois heueuse!" Huit jours après, une grande dame vint chercher'1 Thécla;' M. Offenheim, qu'Eudoxio avait préparé, embrassa la fugitive eu lui demandant do lui écrire souvent. Puis, quand les chevaux partirent au galop, so retournant vers Eudoxie: Ma fille, lui dit-il, vous voilà seule" chargée du pauvre vieillard !9 Dieu vous récompensera.

—11 me récompense déjà, répliqua Eudoxie, puisque vous m'appelez votre fille.»

Sur ses entrefaites, l'armée français, qui marchait de victoire en victoire, et qui marchait très vite, s'empara' de la Saxe,10 mois à titre d'alliée. Napoléon respecta la couronnedu vieux roi seulement, le pays fut occupé par nos troupes, précaution utile aux projets de l'Empereur sur l'Autncho et sur la Prusse. Les généraux, les officiers et les soldats furent répartis chez? les habitants.13 Un général de la garde se présenta, lui et sa suite, avec un billet de logement, au château d'Offenheim.13 Il fallut bien le recevoir, et, encore, le recevoir bien.11 Le général souffrait d'une blessure récente ;15 c'était d'ailleurs un homme jeune encore,16 d'une grande distinction, et aussi doux dans la vie ordinaire qu'il était terrible dans les combats. M. Offenheim l'admit11 à sa table,17 et le Français fut témoin des angéliques vertus d'Eudoxie, dont la grâce l'avait d'abord frappé. Au bout d'un mois de séjour, il fit à l'oncle l'aveu d'un sentiment qu'il cachait le mieux possible aux yeux de la nièce,19 et offrit son nom et sa main.

Le général était dans la plus belle position de fortune et d'ambition,15 favori de l'Empereur et tenant' à une excellente famille d'Alsace.... quasi Allemand par conséquent, ce qui touchait beaucoup M. Offenheim. Le vieillard rajeunissait à cette espérance ;20 l'idée de pouvoir confier, avant de mourir, sa chère Eudoxie à un époux si éminent par sa position, et qui paraissait si digne d'elle par le cœur," répandait sur la figure du vieillard et dans son humeur une teinte de joie inaccoutumée, dont Eudoxie jouissait, sans pouvoir se lexpliquer.

Colloquial Eseecise.

7. Qu'arriva-t-il huit

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jours après

8. Que dit M. Offenheim après le départ de Thécla i

9. Quo re'pondit la jeune

fille?

10. Que fit alors l'armée française?

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ANSWERS TO CORRESPONDENTS.

Excblsior.—The Latin Dictionary is completed in twenty-nine nnmben, and may be bad, bound in neat cloth, 9b. fid.

Geo. Barclay: The fifth volume of the P. E. was completed at the end of last September, and may be had of any bookseller.

Robirt Hudson: We fear it will be imposai We to find room for the proposed contribution.

N. W. N.: We cannot judge of the merits of a composition from merely two or three sentences. The specimen is pretty (rood as far as it goes.

Eooubr: The poetical version is a creditable attempt, but not without faults.

Tat>: For information on the subject of Euclid's twelfth axiom, see "Cassell's Euclid," "Cassell's Self-examiner in Euclid,** or our Ltssoa* in Geometry. It is impossible to define exactly how much classical knowledge a man should have before matriculating at Cambridge. He should, at least, be able to read Xenophon, Homer, Liry, Virgil, and Horace with tolerable ease. In mathematics be ought to be well acquainted with arithmetic, algebra, Euclid, and trigonometry. Of courte the more he knows of both classics and mathematics, the better bis chance of a good degree. Consols are portions of the National Debt consolidated at a certain rate of interest, », e. the Government having, at different times, borrowed money on various terms, put all the sums together and agreed to pay the same interest for the whole. As the value of any debt must vary with the probability of its payment, and the general state of commerce, so that of the National Debt changes according to the circumstances which affect the condition of the Government and the country. Hence the daily alterations in the prices of consols, shares and other securities.

Admirsr: The best books for beginning Hebrew are Arnold's First and Second Hebrew Books. Ux Ami: The problem is Impossible.

J. Tbtlow: Weale has published a good table of Logarithms; Walton and Maberley a still better.

G. M. V.: Trigonometry is derived from rper, three; f*viat a comer or angle; and ^trpav, a measure; and properly means the measuring of threecornered figure*, or triangles. Kor definitions of adjacent angles, etc., see "Cassell's Euclid," or our Lessons in Geometry. We intend, if possible, to give a few lessons in Trigonometry. The other subject is nnceruiu.

LITERARY NOTICES.

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In Two Parts:—1. German and English; 3. English and German. In one large handsome Octavo Volume, price 94. cloth. The German-English Division, price 5s. in paper covers, or 5s. 6d. neat cloth; the EagluhGermau Division, 3s. 6d. paper covtrs, or strongly bound in cloth, 4s.

Cassell's Lrssoxs In German. Parts 1. and II.—Price 2s. each in paper covers, or 2s. 6d. In cloth. Two Parts bound together, price 4s. 6d.

Caswell's Eclectic German Reader: containing choice Selections from the best German Authors, in r/rusc aud Verse. Price 2s. paper covers, or 2s. 6V.. cloth.

Cassell's Lessons In German Pronunciation: consisting of easy Extracts from German Writers. Price Is. paper coveri, or is. Ul. cloth.

frîf A Key to the above Lessous is now ready.

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magnetic meridian, we shall observe that directly a sufficiently powerful current passes along the electro-dynamical cylinder, the latter begins to move, and stops in such a position that its axis is parallel to the declination needle. Further, in the lower part of the circular currents which compose the cylinder, the current flows from east to west. The directive action of the earth upon electro-dynamical cylinders is therelore the consequence of that which it exerts upon circular currents.

In this experiment, as the electro-dynamical cylinder takes the same direction as a magnetised needle, the extremity pointing to the north is called the south pole, as in magnets, and that which points to the south is called the north pole.

Mutual Action of Magneto and Electro-dynamical Cylinders.— "We have already seen that electro-dynamical cylinders exert mutual attraction and repulsion upon each other. The same phenomena take place between magnets and electro-dynamical cylinders. In fact, if you bring one of the poles of a strongly magnetised bar near a moveable electro-dynamical cylinder traversed by a current, there will be attraction or repulsion according as the poles of the magnet and the electrodynamical cylinder are of a contrary or the same name. ConTersely, the eame phenomenon is exhibited if you bring an electro-dynamical cylinder traversed by a current and held in the hand, near a moveable magnetised needle. Consequently, the law of attraction and repulsion is applicable to the mutual action of electro-dynamical cylinders and magnets.

Ampere's Theory on Magnetism.—Guided by the analogy ■which exists between electro-dynamical cylinders and magnets, Ampere propounded an ingenious theory, by means of which magnetic phenomena are brought within the province of electro-dynamics.

Instead of attributing magnetic phenomena to the existence of two fluids, Ampere attributed them to circular voltaic currents around the molecules of magnetic substances.

When these substances are not magnetised, the molecular currents proceed in all directions, and the resultant of their electro-dynamic actions is nothing.

In magnets, on the contrary, the molecular currents being all parallel and in the same direction, their concurring actions have a resultant equivalent to a single current moving circularly on the surface of the magnet, as represented in fig. 451. Hence magnets are merely electro-dynamical cylinders, and magnetic attraction and repulsion nothing but consequences of the action of currents upon currents.

TOi. T.

Lastly, in this theory, to explain terrestrial magnetic effects, electric currents are supposed to be incessantly circulating about the globe from east to west, perpendicularly to the magnetic meridian. It is these currents which direct the movements of the needle in the compass, and render iron minerals magnetic. With regard to their nature, it is supposed that

Fig. 451.

they are owing to the variations in the temperature resulting from the successive action of the sun upon different parts of the globe's surface from east to west.

Magnetisation by Currents.—Judging from the influence exerted by currents upon magnets in deflecting the south pole to the left and the north pole to the right, it is natural to conclude that, in acting upon magnetic substances in their natural state, currents must have a tendency to separate the two magnetic fluids. And in fact it is found that, on plunging a wire traversed by a current into iron filings, they are attracted by it as long as the current lasts, but fall away as soon as it ceases, while every other non-magnetic metal exerts no influence on the iron filings.

The action of currents on magnetic substances is especially evident when we wind a copper wire covered with silk round a glass tube, as Ampere did, and put a non-magnetised bar of steel in the tube. It is found that the bar is strongly magnetised if a current be passed through the wire for a very short time.

If, instead of passing a current from the battery along the wire we pass the discharge of a Leyden jar along it, by connecting one of the ends with the external armature and the other with the internal, we shall still find the bar magnetised. We may, therefore, communicate the magnetic property either by voltaic electricity, or the electricity of a machine.

In the above experiment, the wire may be wound upwards from left to right, thus forming what is termed a right helix, fig. 452, or downwards from right to left, so as to form what

Fig. 4(2.

is called a left helix, fig. 453. In the right helix the north pole of the bar is always at the extremity at which the current enters; the contrary is the case with the left helix.

Fig. 453.

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The nature of the tube round which the wire is wound is not without importance. Wood and glass are productive of no effect; but a thick copper cylinder is capable of completely destroying the effect of the current. It is the same with iron, silver and tin.

Electro-Magnets are bars of soft iron which are magnetised under the influence of a voltaic current, but only temporarily, because as the coercive influence of soft iron is inappreciable, the two magnetic fluids are neutralised as soon as the current ceases to pass along the wire. If, however, the iron is not perfectly pure, it retains more or less evident traces of magnetisation. Electro-magnets are made in the shape of a horse-shoe, as' seen in fig. 454, and a copper wire covered with silk is wound a great many times round the two branches, so as to form two bobbins, A. and B. The wire should be wound in the same direction round both branches, that the two ends of the bar may be two poles of contrary name, the south pole being at the entrance of the current and the north pole at its point of departure.

Electro-magnets are very powerful. Their force depends on the size of the iron bar, the strength of the current, and the

145

length and thickness of the wire. If a soft iron lifter—or armatttri, as it is technically called—be placed at the two ends of the branches of the horse-shoe magnet, it may be made to support very heavy weights, varying according to the size of the electro-magnet.

We shall hereafter speak of the important uses to which the electro-magnet is applied in connection with the electric telegraph, electro-magnetic moving powers, and the properties of powerful magnets. Meanwhile we proceed to give some account of the discoveries and experiments which have been made with reference to electro-magnets,

Tig. 154.

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The important discovery of magnetic induction by electrical currents was made by M. Arago, who was led to it by observing that iron filings are attracted by the conducting wire of a galvanic battery. That this property is magnetic, and not simply electrics), was shown by the fact that the filings of other metals are not similarly attracted, and also by permanently magnetising steel needles enveloped in the spirals of electro-dynamical cylinders. And that the phenomenon is one of induction, was proved by the fact that the filings and needles acquire magnetic properties without contact with, and even at a distance from, the conducting wire.

Nearly at the same time that M. Arago was engaged in making these beautiful and valuable experiments in France. Sir H. Davy was occupied with similar investigations in England; which resulted in the independent discovery of the same facts by each of those distinguished philosophers.

Mr. Sturgeon substituted for the steel needles used by Arago and Davy, pieces of soft iron wire wrapped in spirals of copper, and found that they were rendered intensely magnetic.

Our knowledge of electro-magnetic induction was next extended by the researches of Professor Henry, an American philosopher, who found that the principle of the galvanic multiplier may be applied to the development of great magnetic power in soft iron, by a small galvanic battery; and employed it for the purpose of studying the inductive action of electrical currents upon considerable masses of iron, and of investigating the relative power of currents of different quantity and intensity, as well as of the same current when transmitted through insulated conducting helixes of various lengths, and opposing different degrees of resistance to its motion. The apparatus employed by Professor Henry somewhat n'uled that represented in fig. 154. It consisted of a bar of 2 inches square and 20 inches long, bent in the form

of the letter U, or of a horse-shoe, 9£ inches high, and weighing 21 lbs. avoirdupois. A piece of iron from the same bar weighing 7 lbs. was tiled flat on one surface for an armature or lifter; and the extremities of the legs of the horse-shoe were truly ground to the surface of the armature.

Round the horse-shoe 540 feet of copper wire, well covered with waxed thread to secure insulation, were wound in 9 coils of 60 feet eacn. These coils were not Wrapped continuously round the whole length of the bar, but each strand occupied about two inches, and was wound several .times backwards

and forwards over itself; and the several ends of the were left projecting, and numbered, so that the first and last of each strand could be readily distinguished.

In this marner a large experimental magnet was formed, with which several combinations of wire could be made by merely uniting the different projecting ends. Thus, if the last end of the first wire be soldered to the first end of the second, and so on through all the series, the whole will constitute a continuous coil of one long wire; and by soldering different ends, a double coil of half the length, or a triple coil of onethird the length, etc., might be easily formed. The horse-shoe was suspended in a strong wooden frame, and an iron bar was fixed below, so as to act as a lever of the second order, graduated and counterpoised, so that the weights supported might be estimated by a sliding weight, as in the common steel-yard.

With a single battery («'. *. a battery with one couple), consisting of two concentric copper cylinders and one of zinc between them, excited by immersion in a cup of diluted acid, and exposing a zinc surface of two-fifths of a square foot, the following results were obtained :—

Weights supported in lbs. avoirdupois.

7

145 200

300

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No. of wires soldered
to the battery.

1. Each wire in succession ...
3. One on each side of the arch

2. One from the end of each leg

3. One from each leg, and the other from the

arch ... ..,

4. Two from each extremity
6. Three on each side
9. All the wires attached ...
9. All the wires soldered to a battery exposing

one square foot of zinc surface ... ... 750

9. All the wires attached to a pair of plates

exactly one inch square ... ... 85

From the above experiments, it is evident that a very small simple battery with one couple is capable of producing great magnetic effects, if the spirals of the inducing electro-chemical cylinder are numerous, and the resistance to the passage of the current is not very great.

The effect of varying the length of the conducting wires and the intensity of the current, was satisfactorily shown by the following experiments. Six wires, each thirty feet long, attached to the small cylindrical battery described above, caused the horse-ehoe bar to lift 375 lbs.; and when the same wires were united so as to form three coils of sixty feet, it supported 290 lbs. Hence it appears, that, with a simple galvanic battery, six short wires are more powerful than three of double the length.

The two wires which had sustained 200 lbs. when separated, being united so as to form a single coil of 120 fleet, lifted only 60 lbs. But when a small compound battery of two elements, exposing exactly the same zinc surface as the single battery used in the last experiment, was substituted for it, the weight lifted was 110 lbs., or nearly double.

Also a small horse-shoe, one-quarter of an inch in diameter, wound with eight feet of copper wire, when attached to a simple battery with a zinc plate four inches by s rounded with copper, lifted 4$ lbs.; but when the cu passed through a copper wire 1,060 feet long and -045 of an inch in diameter, it supported only half an ounce; through. 530 feet, or half the same length of wire, it lifted two ounces. The whole length of the wire being then attached to a small compound battery (i.e. a battery with several couples) containing 25 double plates, and presenting exactly the same extent of zinc surface to the action of the acid as the simple battery used in the lasl experiments, the weight lifted was eight ounces;

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