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helix of iron wire, and magnetizing this hollow cylinder by means of the pole of a magnet, in the direction of its axis, this cylinder becomes a transverse magnet, one side of which presents the north pole, and the opposite side the south pole. This phenomenon depends upon the fact already explained (3). Î have shown that a solid bar of iron may be magnetized in the same manner by carrying homonomous magnetic poles on opposite sides in the plane of its axis. By thus treating a quadrangular bar of iron, for example, its four corners will present throughout their whole length the magnetic arrangement already explained with respect to the quadrangular endless magnet; that is to say, one corner will present throughout its whole length the north pole, the following the south pole, the third the north pole, and the fourth the south pole; and the two extremities do not exhibit signs of reciprocal polarity. By the same process, I so formed the magnetic arrangements in a cylindrical steel bar, that in one-half of its length it presented longitudinal magnetism, and in the other half, transverse magnetism. One of its ends has a north pole, and the northern magnetism diminishes to the centre, where there is indifference; here, transverse magnetism distributed throughout the periphery of the other half commences. In this arrangement, these two magnetisms support each other reciprocally.

Let us apply these magnetic phenomena to the electrical connecting wire; we shall there recognize all the properties which belong to transverse magnetism. If the connecting wire is prismatic, e. g. quadrangular or hexangular, we shall then find precisely the same magnetic arrangements as in the transverse magnets of the same form. If the wire has a cylindrical form, the magnetic arrangement is such as it ought to be according to the properties of transverse magnetism; nevertheless this arrangement is apparent, and consequently the cylindrical wire compli cates the phenomena instead of explaining them, as M. Berzelius has already observed. These properties of transverse magnetism, founded on the facts now sketched, explain all the phenomena observed in the connecting wire, not only without difficulty, and without having recourse to any hypotheses of electric currents, or of certain qualities of these currents; we may also predict what will happen by varying the combinations of the experiments to which the connecting wire may be subjected. (See the memoir in the fourth number of Gilbert's Annales, 1821.)

The difference which exists between common transverse magnets and the transverse magnetic charge of the connecting wire, depends upon the nature of the action of the electric pile. Neither this pile, nor any electric force whatever, gives a simple and determinate impulse, as is the case with the action of the magnet, or with a plate of glass electrically charged (leyden jar); but the pile produces and receives these impulses every instant, so that the effect of this action is evident, notwithstanding that every in

stant a neutralization of the electricity or destruction of the electric effect occurs. To this property must be attributed the reason why the pile magnetizes some metals, which are not magnetized to a sensible degree by the magnet; for although these metals have not the power of retaining the magnetic charge, and suffer more or less every instant the neutralization of the communicated electricities; yet as the pile establishes this electric tension each moment, it is impossible that these metals should not exhibit its effect; that is to say, the transverse or magnetic charge. The case is the same with the electric spark, because the electric spark is nothing else than a connecting wire formed by the air, as is proved by the experiments of Sir H. Davy, by the magnetic property of the electric spark.

This activity of the pile prevents, at the same time, the fixed arrangement of the poles in the periphery of the connecting wire, as produced by common magnetization. If, for example, the connecting wire has any kind of prismatic form, the pole of angle Si, fig. 5, which was south, becomes north, when the bar is turned, until the angle Si occupies the place of the angle N 2; and the angle N i, which was north, becomes south, when it enters the place of the angle S i.*

According to this, the researches into the phenomena of the electrical connecting wire resolve into this simple question: Why is a conducting body connecting the two electrical poles charged transversely? The answer to this question enters into the theory of electricity in general, and I shall probably find an opportunity of returning to it. The properties of the transverse electrical charge form a new branch in the theory of electricity. The facts stated readily lead to the result that every transverse electrical charge is magnetic. The reason is, that in the transverse electrical charge, the electrical poles approach each other infinitely near, and on account of this approximation, their tension is increased. Let us suppose that two weak electrical poles of the intensity = i are capable of giving the longitudinal electrical charge to a metallic wire of 100 feet long, and the thousandth of an inch in thickness, and that this longitudinal charge becomes changed into a transverse electrical charge, then the intensity of the poles at the periphery will be greater than 1200000 i. As two very weak electrical poles are capable of giving an electrical charge to a much longer metallic wire, it follows that the electrical tension of the poles in the connecting wire must be very great, in comparison with common electrical tensions, for which the air still preserves its non-conducting power, although it is diminished on account of this tension. It is this great electrical tension of the transverse charge, which makes the metals red-hot, and volatilizes them. This constant and infinitely great electrical tension is magnetic; for electri

These references are not in the figure, but being apprehensive that I might alter the sense, I have not attempted to supply the deficiency.-Ed.

city whose tension is so considerable, that to it all non-conductors become conductors, and some bodies only which were before conductors, become on account of the state of their internal cohesion non-conductors, can only be magnetism. This I have shown in a memoir in the first number of Gilbert's Annales for 1821. If the air were not a non-conductor of electricity, we should not be acquainted with common electricity, but only with magnetism.

ARTICLE II.

Meteorological Account of the Weather during the Three Winter Months of the Years 1821 and 1822, kept at Jasmond, Newcastle-upon-Tyne. With Observations on the Time of the Flowering of various Plants. By N. J. Winch, Esq.

SIR,

(To the Editor of the Annals of Philosophy.)

Newcastle-upon-Tyne, April 8, 1822. CONCEIVING a meteorological account of the weather during the three winter months of the years 1821 and 1822 as it occurred in the north-east of England, may afford amusement to some of your numerous readers, I take the liberty of transmitting an abstract of a journal kept at Jasmond in the vicinity of this town, by Mr. Losh, and kindly communicated by him for that purpose. Together with observations on the state of the weather, notes on the time of the flowering of various plants are interspersed, which, with some general remarks, will serve to convey a correct idea of the mildest winter experienced in this part of the island within the memory of man.

I remain, Sir, your obedient servant,

N. J. WINCH.

Jasmond, one mile north of Newcastle-upon-Tyne, about 200 feet above the level of the river Tyne. Lat. 55° N.

1821.-Nov. 30. This has in general been a mild and pleasant month, favourable to vegetation, and to all kind of farming operations. There were, however, during it, two or three very heavy storms of wind, one in particular in the night of the 30th, perhaps as violent for two or three hours as any within the memory of man. As, however, the wind blew from the W, no great injury has been done by it to the shipping on the coast.

Plants in Flower.-China rose, Portland thorn heath (Erica carnea), jasmine mignonette, purple groundsel, stocks, pansey hollyhocks, wall flowers, carnation, colchicum, gentianella, viola, auricula, primula, Canterbury bell.

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Plants in Flower.-China rose; wall flowers, single and double; stocks, single and double; gentianella (gentiana acaulis); sweet pea; heath (Erica carnea), polyanthus, auricula primula; pansey; blue hepatica; carnations.

The flowers of many of the above, as the carnation, sweet pea, &c. are very feeble, but still sufficient to show the remarkable mildness of the season, or rather the remarkable want of frost. We have not as yet this winter had snow on the ground, nor any frost beyond slight occasional morning hoar frosts. I have never seen the mercury below the freezing point. We have had a good deal of heavy rain, but still in this district scarcely our average quantity; and from the long continued drought in the summer and autumn, I am inclined to think that more would be beneficial. Though, during this month, we have had no very violent wind, yet we have had frequent windy weather, and it

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