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power. Their mutual attraction may also be explained by the laws of action and re-action, which are always equal and opposite to each other.

Neither magnetic attraction nor repulsion is affected by au intervening body; but heat weakens the power of maguctism, and sometimes destroys it: yet its property may be restored, though not its power in the same degree as before. May not this circumstance arise from some of the effluvia having gone off in consequence of heat? Iron when red hot is not attracted by the maguet; perhaps its whole affinity with that power has evaporated.

Philosophers have in vain endeavoured to estimate the force with which the magnetic attraction acts at different distances; but as that law has not yet been fully ascertained, all that we can infer from their observations and experiments is that the magnetic power extends further at one time than at another, and therefore its sphere of action is variable.

A magnet cannot support even its own weight of metal, but its power may be much increased by means of arming, which is thus performed:

TO ARM A MAGNET.

the same degree, and thus it is that the mag-
net supports a greater weight by the commu-
nication. That this is the true cause of its
increased power of attraction is evident by
placing the south pole of another magnet
below the piece of iron; when the same effect
takes place. Presenting the north pole of a
magnet to the first piece of irou produces á
contrary effect; for it diminishes the power
of the first magnet.

EXPERIMENT ON THE INCREASING POWER
OF A MAGNET.

Suspend a magnet by a hook from some fixed point, and attach as much iron to it as it will support together, with a scale, which must also be affixed: and you will find that every day you may put additional weight in the scale, and the magnet will support it; which shews that its power is constantly increasing.

It is supposed that the iron, becoming magnetic, increases the power of the magnet in the manner before described. When the iron is removed from the magnet, the power of the latter is rendered weaker than it was before the experiment was made. This illustrates the theory of pinus, that the magnetic fluid is unequally distributed in a magnet which has a fixed polarity, one pole being overcharged, while the other is undercharged with it: and that there is always a strong attraction be tween these contrary poles, in consequence of this unequal distribution of power; but when a piece of iron is presented to either, that, by its becoming possessed of a contrary polarity to that of the magnet, the power of each end on the other is weakened by the communica tion, and thereby its individual power in

Cut the magnet into a parallelopipedon, and let its two poles be parallel planes: place this magnet in an armour of soft iron, which, having a cross piece, with a hook attached, will support great weights suspended from it. The advantage gained by arming is very considerable, a magnet that will of itself support four or five ounces, will when armed sustain twenty times that weight. A magnet and its armour may be enclosed in any material excepting iron. The power of a magnet may also be aug-creased; for there is in every magnet a strong mented without arming, by simply introducing another piece of iron below that it at first supports; as is evident on presenting to it a piece of iron heavier than it can sustain, and afterwards holding under it another piece at a small distance from the former, when the magnet will support what before it could not lift. The cause of this is assigned by Cavalio to the last piece becoming magnetic, and so increasing the attraction of the first piece, and in the following manner. The end of a piece of iron which is presented near the north pole of a magnet becomes possessed of the south, while the other extremity possesses the north polarity. Again, the second piece being held near to the north pole of the first piece of iron, acquires a south polarity. This must increase the north power of the first piece, when its south power must also be augmented in

attraction between its poles; but whcu another substance, or a magnet, is presented to either, the effect is stronger by being drawn from the contrary pole. Hence we may sup- pose that a magnet becomes continually weaker when left alone, so that it is necessary either to place it in armour, or leave a piece of steel or iron on its poles; because at these points the powers are at the greatest distance from each other's effects.

It is not more extraordinary than true, that the magnetic power may be acquired without the application of a magnet, and by friction be made to communicate that power to iron or steel. Rubbing one piece of iron on another will produce evidences of the magnetic virtue; and even a certain position of either, long continued, will render that effect permanent. The famous philosopher of our

OF THE DECLINATION OF THE NEEDLE.

The north pole of the magnet, in every part of the world, points nearly north; yet it very seldom shews that direction exactly. Hence the magnetic meridian seldom coincides with the observed meridian of any place on our globe, but generally varies either to the east or west. This variation is not uniform at different places, nor does it always agree even in the same place; at London, for instance, in the year 1640 it was 11° east, but now it is 239 west. This variation is always reckoned from the north, either east or west. The directive power of magnetism, though generally exhi

country, Dr. Gilbert, in the sixteenth century, observed that the small bars of a window which were placed obliquely to the horizon, and nearly north and south, by remaining in that || situation for many years became magnetic. The polarity thus communicated may be from the earth and its atmosphere; for all the effects of magnetism evince that the power is derived from those sources, though the peculiar directive power cannot be traced to its primary natural cause. The particles of iron being universally diffused through all auimated nature, as well as in all substances in the earth, may not a magnet have some effect on the animal economy? As this universal diffu-bited by a touched needle, is also evident in sion of iron fully justifies the idea that the magnetic fluid is one of the elements of the earth and its atmosphere, may we not also conceive the magnetic effluvia to be equally disseminated through the globe, in such bodies as do not exhibit any evidences of its existence: and that is visible effects result from that equilibrium being destroyed?

EXPERIMENT ON THE ACTION OF THE POLES

ON EACH OTHER.

The dipping-needle serves to shew the action of the two different poles on each other; for on presenting the north pole of a maguet to the south pole of the needle, it is attracted; but if we present the same pole of the magnet to the north pole of the needle, it is then repelled and flics from the magnet. Strew steel filings on a pane of glass, and put the north pole of a magnet under it, they will then rise on the paper; but on holding the north pole of another magnet directly over these filings, they will immediately fall. Dip the north pole of one magnet and the south pole of another in steel filings, and bring the ends of the bars toward each other; then the filings will unite. But dip the two north poles and bring them in contact, and the filings will

recede from each other.

Two magnets placed in a straight line at a small distance from each other, the south pole of one opposed to the north pole of the other, with a pane of glass over them; on sprinkling steel filings, and tapping the glass to produce a little motion in the filings, they will arrange themselves in the direction of the magnetic fluid; those lying between the two poles, and near the axis, being disposed in straight lines, going from the north pole of one magnet to the south pole of the other. Reverse the oder of the magnets, by placing the two poles of the same name opposite, and the filings will be arranged in curves receding from each other.

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small bars of steel or iron freely suspended; as may be seen by fine pieces of either floating on the surface of water; but to exhibit this property, they must remain some hours, when they will point nearly, if not exactly, north and south.

The directive property of the magnet, according to Dr. Hailey's hypothesis, is supposed to arise from the current of the magnetic fluid issuing from a central magnetic globe, which passing through the earth and its atmosphere, causes light bodies to move with it.

To account for the direction of the magnet being variable, and this variation not regular at the same place, nor in an uniform degree at the same time at different places, various hypothesis have been formed, and some truly curious and interesting experiments have been made to illustrate them, of which number the following appears the most ingenious and satisfactory.

Messrs. de la Hire, senior and junior, formed a globe out of a very large magnet, aud by suspending it, found its poles; they next traced out its equatorial and meridional circles. The globe was about a foot in diameter, and weighed one hundred pounds. Placing it due north and south, and in a position that answered for the latitude of the place of observation, they perceived its declension east and west, in regard to situations of places on it. From these remarks they inferred that the magnetic fluid is diffused through the whole earth, and obeys the universal laws of magnetism; yet they do not explain the causes of the different variations of it at the same place. The regular declination observed on the magnetic globe was owing to the equality of contexture in its parts, and the varying magnetic force at different places on its surface. But as the contexture of the earth is very irregular, perhaps that circumstance, united with the numerous processes carrying on within it,

is the cause of the variation. Perceiving that the regular variation on the magnetic globe arose from its uniform contexture, we may infer that the inconstancy of the variation of the needle on the globe of our earth arises from the inequality of its parts. No perfectly satisfactory hypothesis having yet been formed respecting the variation of the needle that can be authenticated by facts, it is impossible to foretel what this irregularity will be at a future time at any particular place, or other circumstances depending on that knowledge, though derived from the experience of a long continued series of observations.

The ingenious Mr. Canton discovered a new variation of the magnetic needle, which he communicated to the Royal Society. Observing the direction of a touched needle for a whole day, he perceived that it was never perfectly at rest; that its western declination from the pole was greatest in the morning, and least at night; about noon in a medium of its diurnal variation. He offers the following rational solution of these phenomena, founded on the known fact, that a magnet when heated loses something of its natural force. He supposes the direction of the needle to be occasioned by the attraction of the magnetic fluid, and that the attraction is strongest where the heat is weakest; therefore that the needle at sun-rise with us is not so forcibly impelled towards the east, because the magnetic force is lessened by the sun's influence; consequently the needle points rather more westerly at that time. When the sun is on our meridian, the variation is not changed, the action of the sun on cach side of us being then equal; towards evening the needle points more easterly, because it naturally points to the part within its range the least heated by the sun.

EXPERIMENT.

This effect may be understood by heating a magnet, and placing it on one side of a needle,|| and another magnet in its natural state on the other side, when the needle will decline from the heated one. Mr. Canton perceived, from repeated experiments, that the diurnal variation of the needle was about 20 minutes of a degree, from sun-rise to sun-sef.

OF THE DIP OF THE MAGNETIC NEEDLE. The needle has a dip, or inclination; the cause of which, like every other peculiar cha

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racteristic of this curious phenomenon, is un known. It may be seen, by placing an untouched needle on a pivot, and presenting a maguet to it, when it will incline towards a point below our horizon. To counteract this effect, the mechanist who constructs compases, files off part of the inclining end, and by that means balances the needle on the pivot. The inclination of the needle is as variable as ita declination. It also varies at different parts of the earth at the same time. The idea of the inclination having reference to latitude only is a mistake, it being as irregular in that respect as the declination; for at Paris in 1800 it was 72° 25' north, and at Siena 13° south. No doubt these variations depend on the same causes as those of the direction of the needle.

THEORY OF MAGNETISM.

The whole that can be inferred of the nature of the phenomena of the magnet, is briefly this:that it attracts bodies in the earth; and that it has a directive power which is variable, arising perhaps from the unequal diffusion of the magnetic power in the earth and atmosphere, depending on the different constitutional circumstances of each of them, together with the effects of heat and cold on that power. Its attraction is evident on bodies on the earth; and we know that the earth contains bodies of this attractive nature, for from the earth they are procured; and we must suppose its direction depends on the inequality of attrac tion in the earth. The variation in that direction may also depend on the parts which contain the attractive power being more or less heated. These natural and hidden causes being incalculable by us, we never must expect to arrive at a perfect knowledge or estimation of

them.

The magnetic fluid may be either formed of two kinds of elements united by affinity; these elements having a greater tendency to each other than to themselves: or the phenomena perceived of attraction and repulsion, in the former case, may be produced by the endea vour of the disturbed effluvium to place itself in equilibrium, and in the latter form its natural repulsion to itself. The directive power of the needle, and the mode of constructing com passes, are so well known, that it would be superfluous to introduce them here.

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which this occurrence plunged Mr. R
very nearly made him have a relapse, and he
only recovered his good humour at the next

MR. R――, was one of the most celebrated epicures of his time. Being very rich he needed nothing but a good appetite to satisfyindigestion. it to the fullest extent; and his house was always well stored with every delicacy which money could procure. He would devour a pigeon-pye with the same ease as if it were a twopenby cheese-cake, swallow truffles like s many cherries, and cat a fricasseed chicken for his luncheon. But his wife, who doubtless feared widowhood, incessantly contradicted him, and thwarted him in all his tastes, so much so, that in order to enjoy himself at his ease he was obliged to shut himself up, and not allow her admittance, in order that he might, without any obstacle, yield himself up to the delights of epicurism. At length, however. he fell ill; and the remedy prescribed by the faculty was a strong dose of medicine, and a strict regimen. This was for our epicure the most unwelcome order in the world, and he would certainly have very ill complied with it, had it not been for the vigilance of Mrs. Rwho took possession of all his keys, and assuming the station of his nurse, made him act completely according to her wishes, as is always the case with those who are confined to their beds. The medicines were of service; Mr. R was much relieved, and judged to be in a state of convalescence. At length he || was permitted to eat; and the physician, well aware of his weak side, scrupulously ordered || the exact quantity of food he should take, which consisted for the first time of a soft egg, and one round of toast. Mr. R- would This monthly course of emulation, in which rather that the egg should have been laid by each town would seek to cut a figure, by spara an ostrich than a fowl, but he consoled himself ing no pains to outdo their rivals, would very in thinking of the toast; he caused the largest speedily bring about a visible amelioration in loaf that could be procured to be bought, so all the productions of the culinary system; that when made it was more than a yard long, poultry would be more carefully fattened, and weighed nearly a pound. Mrs. R pastry kneaded more scientifically, game more would have interfered but without success, as skilfully selected, and not whether old or he only followed the physician's ordinance.young, tender or tough, indiscriminately put The egg was ushered in with great solemnity, and placed on the sick man's bed, who proposed himself a great enjoyment; but, fatal misfortune, he sipped the white with so much avidity that he swallowed the yolk! O dire calamity, deplorable preci itation, which rendered the delicious toast completely useless; and Mrs. R- gravely caused it to be taken away with the egg-shell. The despair into No. XXV. Vol. III.

A PLAN FOR THE IMPROVEMENT OF THE
CULINARY ART.

It would be highly beneficial to the culinary art, that all the new discoveries and inventions || which take place during the period of each year, should be carefully recorded for the increase of our present enjoyment, and for the advantage of future generations. A periodical work of this nature, which, to avoid the frequent expence of stamp duties (which often paralizes thought even in its birth) need only appear once a month, would be of infinite utility. All that the genius of good living each day delights to invent, would be faithfully recorded; the progress of each ingenious artist would be made known, and their constant efforts to deserve public approbation; added to which a long list of all kind of provisions would be given, and the whole to conclude with an account of all the celebrated indigestions that have taken place, with their causes and effects. This work might also become a channel of correspondence between the epicures of every country. It would establish a medium of communication between all large cities for every thing relating to cookery; each town already celebrated by its alimentary productions, or that wished to acquire a name, would exert all its abilities to merit a place in the proposed publication.

to the spit; pickles and preserves would be more cautiously prepared; in short, the glory of each town and country would be interested that nothing beneath the standard of mediocrity should reach the capital; for this periodical work would exercise on these productions a criticism as severe, though far moreim partial than the Reviews is on every publication, and Newspapers on our most favourite comedians. U u

An undertaking on the above plan would insure success, for every town and city would take an interest in its support, and every truc born epicure would joyfully contribute something to its improvement. But a considerable sum would be required to establish a work of this kind, as it would need a very extensive correspondence, and numerous travellers must be kept at a high salary, in order to make discoveries, and these must be men scientifically acquainted with the art. It is true that this advance would soon be repaid with interest; as many celebrated provincial epicures, animated with the zeal of furthering so glorious a cause, stimulated with the hope of being

made honourable mention of in this work, would not delay in offering themselves as gratuitous travellers. Subscribers would come in crowds, and the Editor's table would daily be covered with exquisite dainties which, as presents, would shower upon them from every quarter. We do not applaud ourselves a little for having conceived this plan, and hope that some of our readers will put it in execution; but while waiting in the hope of our wishes being realized, we will in our next give an account of a few discoveries that have been lately made on the Continent, and which our correspondents have kindly forwarded to us.

POETRY,

ORIGINAL AND SELECT.

ON THE APPROACH OF WINTER.
STAY, sylvan friend, with plenty blest,
Who scorn'st the niggard's icy breast;
And as alone, at early morn,
You brush the thicket, trace the lawn,
List to what sings Amintor:

To thee the friendly hint is sent,
Where inore than meets the ear is meant;
The while, with dog and gun, you roam,
Think on your townsman, far from home,
Deny'd the sports of winter.

When Easter chicks begin to crow,
And azure decks the mountain sloe;
When forest trees wear sickly hues,
And agues wait on evening dews,

Lay up health, nor stint her :
Prepare the ham, the chick, the chine,
Nor spare the produce of the vine;
Fill, fill thy stores with brightest coal,
And something for the Christmas bowl,

To cheer thy friend in winter.
The reaper's moon and harvest past,
Rude blows the equinoctial blast,
Ah! now, my rural friend, beware,
This season claims thy utmost care;

Health bids thee store, nor stint her:

Survey thy cot, secure thy roof,
Soon make it rain and tempest proof;
So when the sable cloud falls low,
Thy heart shall yield the pleasing glow,
That sooths the rage of winter.
Re-furbish up thy warm surtout,
The buckskin glove and friendly boot;

And let the hat that shields thy head,
Around its ample cover spread;

This do for health, nor stint her:
Above the rest, be this your care,
Use exercise and morning air;
And this you'll find of such avail,
While city fops look thin and pale,
You'll wear the rose in winter.

THE FILBERT.

NAY gather not that filbert, Nicholas,
There is a maggot there, it is his house,
His castle-oh commit no burglary!
Strip him not naked, 'tis his clothes, his shell,
His bones, the very armour of his life,
And thou shalt do no murder, Nicholas!
It were an easy thing to crack that nut,
Or with thy crackers or thy double teeth-
So easily all things may be destroyed!
But 'tis not in the power of mortal man
To mend the fracture of a filbert shell.
There were two great men once amused them-
selves

With watching maggots run their wriggling race,

And wagering on their speed; but Nick, to us
It were no sport to see the pampered worm
Roll out and then draw in his folds of fat,
Like to some barber's leathern powder bag
Wherewith he feathers, frosts, or cauliflowers
Spruce Beau, or Lady fair, or Doctor grave.
Enough of dangers and of enemies
Hath nature's wisdom for the worm ordained;

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