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unnecessary and useless encumbrances. But let all such disconsolate persons take comfort. Although the September pull is expected to be a little less strong than the pull of March, there is a third party, one Eolus, who may think proper to have a voice in the matter; and if he vote on the same side with Phoebus and Diana, the tide will be a plumper.

Meanwhile, expectant observers of this tidal feat may like to hear a few particulars of the nature and manner of the pull in question.

than the carth's attraction-such as the arm of a man or the jaw of a hog-robs the earth of the apple it had taken to itself.

There are two conditions to this law of attraction which it is necessary to know. First: The Attraction exerted by a body is directly proportional to its mass. In simpler language, the larger and more solid a body is, the harder it pulls, at equal distances. An object a hundred miles away from the Sun, is pulled much more violently than the same object a hundred miles away from the Earth; while the pull it will receive a hundred miles away from the earth is considerably stronger than that it would experience if suspended a hundred miles above the Moon. All this, for the reason that the mass of the Sun is much greater than that of the Earth, and the mass of the Earth much greater than that of the Moon.

How large is the disproportion of the masses of the Sun and the Earth, may be briefly mentioned: they are to each other as the sum of 1,400,000 is to 1. The Sun is fourteen hundred thousand times as big as the Earth. But abstract numbers impress the mind faintly.

In vast and profound Oceans, and on their coasts, it is observed that the waters rise and sink alternately twice a day. For six hours or thereabouts, they rise, spreading over the shores; this is called the flux, the waters are said to flow, the tide is rising. For a short space of time, a few minutes only, they repose in equilibrium, neither rising nor sinking, which is termed high water; after which they subside again for about six hours, which is called the reflux, or ebb-tide; at the end of which period and a similar short repose denominated low water, they flow again. And so on, throughout all time. During the flow of the tide, the waters of rivers are swollen, and are driven backward A professor at Angers, in France, wishing to a distance from their mouth varying with the to give his pupils a tangible idea of the cominclination of their bed. In rivers that run parative sizes of the Earth and the Sun, set through a level country, as the Thames, the tide them to count the number of average-sized mounts a considerable way inland; while, in grains of wheat contained in the measure called mountain streams which rush headlong into the a litre (about a pint and three-quarters). They sea down a rapid slope, the tide may only influ- found ten thousand. Consequently, a decalitre ence the small portion that lies between high (or ten litres) would contain a hundred thousand and low water mark. During the reflux, the grains, and a hectolitre (or a hundred litres) a liberated streams recommence the task of pour-million. A hectolitre contains a trifle more ing their contents into the bed of the sea. than a three-bushel English corn-sack. The The principle on which the theory of the tides professor then heaped together one hectolitre is founded, is simple; because it is universal and four decalitres of wheat, containing in all in its application, and admits of no excep- 1,400,000 grains. Taking a single grain and tion whatever. No plea, no excuse, can exempt placing it opposite to the heap, he said, "This anything from submitting to its sway. A few is the volume of the Earth, and that is the vohard words, easy to explain and easy to under-lume of the Sun." stand, are the only impediment to its being readily comprehended by the popular mind. Anacreon's bacchanalian ode, to the effect, "the clouds drink the dew, the rivers drink the clouds, the sea drinks the rivers, the sun drinks the sea, the moon drinks the sun; everything in heaven and earth drinks; therefore why should not I drink ?" becomes a rough description of the system of Nature, as far as we know it, if, for the word " drinks," we substitute "pulls," or "draws." The Newtonian force of Universal Gravitation or Attraction is believed to be the law by which the framework of the universe is held together. Attraction, which is only a Latin word for "pulling to," is the game which But, another condition is mixed up with the is unremittingly played by every particle of question of attraction; for, secondly, the force. created matter. Every material body, great of gravitation is in inverse proportion to the or small, attracts every other material body. square of the distance; in other words, a body's It is a constant struggle which body shall annex, attractive force diminishes in proportion to the appropriate, draw, all other bodies to itself; square of the distance. The square of any in this, the strongest body gains the victory. number is that number multiplied by itself; The earth is a ball; an apple on a tree-top is 49 is the square of 7, and 81 is the square of 9. also a ball; but if the apple's hold on the branch Therefore, the attraction exerted by a body, as be loosened, the big ball soon pulls the small ball the Moon, on an object at the respective disto itself, and keeps it, until some stronger force | tances of 7 and 9 miles away from it, will be

The disproportion of magnitude and weight is much less between the Earth and the Moon than it is between the Earth and Sun. In comparison with the size of our globe, our satellite is not so contemptibly little as our globe is in respect to the great centre of the Solar System. The mass of the Moon is eighty-four times less than that of the Earth. It would take eightyfour Moons put together to make one Earth. To follow out the French professor's illustration, if we pile a heap of eighty-four oranges, and place a single orange opposite to the pile, we may say, "This is the mass of the Moon, and that is the mass of the Earth."

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diminished, at the greater distance, in the proportion of 49 to 81; that is, if 81 represent the attractive force at 7 miles' distance-at 9 miles it will only be 49. This rapid diminution of attractive force with increase of distance explains how the immense Sun, an enormous way off, may have a weaker pull on an object at the surface of the Earth than the small Moon, which is comparatively close at hand.

remained perfectly still in relation to each other, the waters so raised would remain in a permanent heap; there would be a permanent alteration of the shape of the globe, and that is all. But, as the Earth revolves on her axis, the solar tidal wave carried on by that movement, like everything else on the Earth's surface, rushes back after the attractive force of the Sun; and, as the Moon revolves round the Earth, there is a similar rushing of the lunar tidal wave, caused partly by the Earth's revolution on her axis, and partly by the Moon's changed place in her orbit. In these complicated influences lie some of the causes which produce our changing and yet periodical tides.

The

As the Earth revolves round the Sun, not in a circle but in an oval, her distance from the Sun is constantly varying slightly; the same thing obtains with respect to the Moon and the Earth. The distances, therefore, from the Earth to the Sun and from the Earth to the Moon, when mentioned in leagues or miles, must be understood The strength of the tides, as well as the hour to be the mean or average distances. The mean of the day at which they occur, is governed by distance of the Earth from the Sun is 95,576,240 the place of the Moon in her orbit, whether miles. The mean distance of the Moon from she be in syzygy or in quadrature (in conjuncthe Earth is 239,100 miles. Consequently, were tion or opposition). Let not those hard words there a railroad from the Earth to the Moon, frighten us; for the explanation of a word-its with trains going at the rate of 30 miles an hour, etymology or derivation-often clears away a it would require 7970 hours, or 332 days and 2 difficulty. As the Moon revolves round the hours, or nearly 11 months, travelling night and earth in a plane which is nearly the same as the day, to pay a visit to the hills and dales of our plane of the ecliptic or the plane of the Earth's bright attendant. At the same speed of loco-orbit round the Sun, it follows that, once in motion, to reach the surface of the Sun would every lunar revolution, the relative position occupy a period of 363 years (of 365 days each), of the Sun, Moon, and Earth, must be this, 249 days, 17 hours, and 40 minutes. Many E- ·M -s, which is called "in conjunction" generations of men must be born and die on the (with the Sun), and once this, M- -E-S, road, in a railway carriage incessantly dashing which is called "in opposition." The former along at a pace of 30 miles an hour, before their takes place at every New Moon, the latter at posterity could arrive at the great central lumi-every Full Moon. Both are called syzygy, from nary. The Sun is about four hundred times a Greek word meaning "a yoking together. further from the Earth than the Moon is. The Sun and Moon draw in couples; they both pull important point is the great diminution of the in one direction. The lunar and the solar attractive force of so large a mass, which is the tidal waves are combined; the waters rise to consequence of so wide an interval. an unusual height; spring tides are the result. It happens, then, that two distinct forces, the Of course their contemporaneous absence during attraction of the Sun and the attraction of the the interval between two high waters, occasions Moon, are continually pulling at the entire mass an unusually low ebb. The highest tides of all of the Earth on which we dwell. The solid por-will occur at conjunction, because there is then tion of the globe-rocks and dry land, moun- a combination of attractive force as well as an tains and continents-hold together, and obey identity in its direction. the combined attractions impressed upon them, all in one piece, in a rigid state. But it is otherwise with the liquid portion of our globe, the outspread oceans, which do not hold together rigidly as if they were frozen, but which flow in the direction of the attractive force, by the same law which causes a brook to stream down a mountain-side, in obedience to the Earth's attraction. And, as the Oceans cover so large a proportion of the surface of the globe, the entire globe may be roughly compared to an india-rubber ball which is pulled out of shape by a couple of strings. There will be a bulging out at the places where the strings pull hardest. It is thus that the attractions of the Sun and the Moon pull the watery parts of the Earth out of shape. The Ocean is raised in a tidal wave or waves; for, there is a solar tidal wave, caused by the Sun, and a lunar tidal wave, caused by the Moon. The latter is about three times as great as the former, in consequence of the nearness of the Moon, and the distance of the Sun. If the Earth, Sun, and Moon, all

But, when the Moon has performed a quarter of her orbit from either of those positions, that is at her first quarter or her third, the three heavenly bodies (for the Earth is a heavenly body) are no longer in the same line. On the contrary, they are at squares, in quadrature, forming a right angle of which the Earth is the

M

corner, thus, EL -s, or ES. The Sun and

M

the Moon, then pulling different ways, will reduce each other's tidal wave. Union makes strength; division weakness. The tides are weak, or neap; the oscillation of the sea is less; high water is never so high, and low water is never so low, at quadratures as at syzygies.

Wherever the movement of the waters of the Ocean is not impeded by islands, capes, straits, and other similar obstacles, the tides are observed to have three distinct periods: the daily period, the monthly period, and the annual period. Of the two first we have already spoken, as the flux and the reflux, and the spring

tides and neap tides. The third, the annual position of the centre of gravity of that weight period, is what will bring about the expected are sufficient to retain the whole vessel, with high tide of the 16th or 17th of September-its masts and rigging, in constant stable equibecause the tide which will happen about mid-librium. In the case of unstable equilibrium night (according to the locality) between the the reverse takes place; a very slight disturb16th and the 17th may perhaps attain the ing force suffices to upset the whole system so maximum of elevation. The annual period is constituted. An acrobat balances a ladder on manifested at the equinoxes, in March and Sep- his shoulder; on the ladder, perhaps will mount tember, by the spring tides being higher and a child carrying flags, chairs, and sundry articles. the neap tides feebler than at other epochs of The whole are in unstable equilibrium. Althe year. At the equinoxes, there is a greater though the skill of the acrobat may put the inequality in the tides generally; at the solstices, whole system, for an instant, in exact balance, there is a greater general equality. still the slightest tremor or puff of air, causing his burden to lean ever so little on one side, would precipitate the whole to the ground, were he not, by slightly changing his position, to obviate that tendency by restoring the balance.

If the equilibrium of the Ocean be of this latter kind, unstable, the waves caused by the action of the winds, by earthquakes, by sudden displacements of the bottom of the sea, have been able in former times, and will be able at future times, to rise to the summits of the highest mountains. The geologist will have the satisfaction of drawing from these prodigious oscillations, a rational explanation of a great number of phenomena; but then the world must be regarded as liable to new and terrible catastrophes.

The cause of these equinoctial high tides, is, that the Sun is then crossing the equator, at which point he is able to give the hardest pull at the bulging waters; he is either actually on the line, or only a little above or below it at the time when the Moon also crosses the equator, and is in syzygy, and sometimes also at her shortest distance from the Earth. It appears, therefore, that the tides are the effect of a combination of varying forces, and that their magnitude is exactly proportional to the strength of those forces. By elaborate and complex calculations, modern astronomers, led on by Laplace, are able to predict the hour and the height of every tide, with a precision which is the admiration of thinking persons. If we suppose the Moon's orbit so changed, that at certain times she would approach the Earth We may take comfort, however, from Laplace's much nearer than she does, the consequence assurance that the equilibrium of the Ocean is would be tides of such force and elevation as to stable: on the express condition, however (which devastate whole continents. Yet their height, is established by indubitable facts), that the and the date of their occurrence, would be cal-mean density of the liquid expanse be inferior culable, if men were left to calculate them. However curious we may be to have a nearer view of our splendid satellite, it is better for us, on the whole, that she should continue to keep her present respectful distance.

to the mean density of the Earth. He also assumes that no change will ever occur in the position of the Earth's centre of gravity, like that which forms the basis of Adhémar's theory of periodical deluges. But if, for the actual Ocean (everything else remaining in the same state), we substitute an ocean of mercury, the stable equilibrium will have vanished, the liquid will frequently burst its limits to rush sweeping over terra firma, and will mount even to the snowy peaks above the clouds.

The exact state of a tide, at any moment, as well as the points of high and low water, may be known in a seaport town by the contrivance of a well having a subterranean communication with the sea, so that the water shall rise in it during the flow, and sink in it during the ebb. By causing the water to enter a tube of Although the phenomena of the tides be this kind by a small orifice, the agitation of the owing to the action of the Moon and the Sun, waves without is rendered insensible. Tide- nevertheless many peculiarities attending them wells of this kind, constructed by M. Chazallon, still remain imperfectly explained. For instance, the French naval engineer, exist at Cherbourg between the tropics, with a few exceptions, the and at Brest. The height of the tide is self-re-tides are very feeble, although the action of the gistered by an instrument called a marégraphe. two great luminaries is there perpendicular to the Laplace was not satisfied with perfecting the surface of the water. In some of the South Sea mathematical theory of the tides; he looked at Islands, there is only one tide per day. Calcuit in quite a novel point of view, and was the lation demonstrates that the rising of the waters first to treat of the stability of the equilibrium is slight in proportion as a sea is small; and we of the seas. All systems, or collections and find that the tides are scarcely perceptible in combinations of bodies, whether solid or liquid, the Caspian, Mediterranean, White, and Baltic are susceptible of two sorts of equilibrium, which | Seas, which are almost lakes: having either no must be carefully distinguished. In stable real or no considerable point of communication equilibrium, the system, if slightly disturbed with the Ocean. In the Black Sea the tides are from its usual position, has a ceaseless tendency to return to it. A well-ballasted ship, sailing with a side wind, leans a little out of the perpendicular, but rights again as soon as the wind falls. The weight of the hull and

almost insensible; they ought to be still feebler in the Baltic and the White Seas, in consequence of their distance from the equator. In the Gulf of Venice, the tide is more perceptible than in the rest of the Mediterranean: which

may be owing to its shape having a tendency press the waters into a heap.

to

One long pull which the tides may have taken, is, the drawing of Old World productions to the coast of the New. The sea, by its general motion from east to west, cannot help carrying to the American shores many things which it has stolen from us; whereas it is only very irregularly, and probably by the action of the winds, that it brings hither, any Indian or American productions.

As a corollary from what precedes, we may feel inclined to take it for granted that there are tides also in the atmosphere, and that our satellite must have great influence on the weather. The popular notions of the changes of the Moon affecting the weather, and of prognostics derived from the appearance of the Moon, support the belief that atmospheric tides exist, and must consequently manifest themselves in their effects. The contrary turns out to be the case. Our elastic and agile atmosphere eludes the Moon's grasp. On the theory of Universal Attraction, the Moon's action on the liquid portion of the globe and the phenomena of maritime tides are explained without difficulty; but, for the influence of our satellite on the gaseous envelope which wraps the Earth, we are still in search of facts and data.

A final word must be hazarded on the attacks and insults to which the oldest-established theories are exposed. What theory can have a better position in the world than Newton's Universal Gravitation? It is no parvenu; it has ancestral claims to respect, and innumerable vested rights in the domain of science. Never theless, irreverent heretics are beginning to pelt it with paper missiles. William Adolph publishes The Simplicity of Creation, a new theory of the Solar System and the Tides, the latter being caused by pressure, and not by the Attraction of the Moon. M. Faye, the eminent French astronomer, thinks he has discovered a new force, totally different from gravitation, which, if he could but confirm it by actual experiment, would replace attraction in the explanation of celestial phenomena. Another scientific speculator, a working man, who signs himself "Rollande," as if he were a peer, shouts to the astonished public that he has caught the unknown force, and is ready to demonstrate its action by a pretty little exhibition. A repulsive force, emanating from the Sun, would seem to be the sole cause of the tails of comets. But electricity is the only known force which possesses repulsive properties. Try, therefore, the following easy experiment:

A ball of elder-pith, or (better) of cork, suspended by a silken thread and put in presence with a stick of electrised sealing-wax, is immediately attracted thereby, and held in contact with it, until it is saturated with the fluid. At that point, the ball is repulsed to a greater or less distance, according to the size of the electrophore or the lightness of the ball. This part of the experiment most people are familiar with. But more surprising things are in store.

If you give to the electrophore a slight circular movement, the ball trembles, shifts its place, and performs a complete revolution round the electro-magnet. For several seconds, the ball describes a circle, but the orbit shortly becomes elongated. A major and a minor axis are formed, and the ellipse is complete with a wellmarked aphelion and perihelion. If your surprise at this extraordinary and unexpected motion allows you to pay a close attention to the movements of the ball, you perceive that it assumes a rotatory motion (which would be continuous were it not prevented by the twisting of the silken thread of suspension), and which takes place in an opposite direction to the motion of the ball in its orbit. The greater the density of the ball, the greater is its rotatory activity; the lighter it is, the less that motion is perceived.

This is not all. If you have made, in the upper part of the ball where the thread comes out, a funnel-shaped hollow, and if you throw into it a few grains of sand, the ball, without any interruption of its course, approaches nearer to the electrophore; and in proportion as more sand is added, the diameter of the orbit is diminished. So that if you continue to put more sand, the ball will at last adhere to the electrophore, which has no longer the force to repel a mass whose density has been increased by successive loadings with sand. Consequently, every ball that revolves round a magnetic centre, has a fixed place which it must occupy.

Now, if while the ball is describing its ellipse, you bring another ball saturated with electricity close to the orbit of the first, you will observe, when the two balls are at the shortest distance from each other, a movement of retreat on the part of both, which constitutes a veritable perturbation; but, as soon as that point is passed, the ball which revolves will continue its motion and the other will fall into its original position. The experiment, which displays an extraordinary coincidence between the movements of the ball and those of the planets, may be repeated whenever the atmosphere is in a suitable hygrometric condition. Wet weather is unfavourable to success.

THE LEGEND OF LITTLE PEARL.
"POOR little Pearl, good little Pearl!"
Sighed every kindly neighbour;
It was so sad to see a girl

So tender, doomed to labour.

A wee bird fluttered from its nest
Too soon, was that meek creature;
Just fit to rest in mother's breast,
The darling of fond Nature.

God shield poor little ones, where all

Must help to be bread-bringers! For once afoot, there's none too small To ply their tiny fingers.

Poor Pearl, she had no time to play

The merry game of childhood; From dawn to dark she worked all day, A wooding in the wild wood.

When others played, she stole apart

In pale and shadowy quiet,
Too full of care was her child heart
For laughter running riot.
Hard lot for such a tender life,
And miserable guerdon;
But like a womanly wee wife,

She bravely bore her burden.
One wintry day they wanted wood
When need was at the sorest;
Poor Pearl, without a bit of food,
Must up and to the forest.

But there she sank down in the snow,
All over numbed and aching:
Poor little Pearl, she cried as though
Her very heart was breaking.
The blinding snow shut out the house
From little Pearl so weary;
The lonesome wind among the boughs
Moaned with its warnings eerie.
To little Pearl a Child-Christ came,
With footfall light as fairy;

He took her hand, he called her name,
His voice was sweet and airy.

His gentle eyes filled tenderly

With mystical wet brightness: "And would you like to come with me, And wear this robe of whiteness?"

He bore her bundle to the door,

Gave her a flower when going:
"My darling, I shall come once more,
When the little bud is blowing."
Home very wan came little Pearl,

But on her face strange glory:
They only thought, "What ails the girl?"
And laughed to hear her story.
Next morning mother sought her child,
And clasped it to her bosom ;
Poor little Pearl, in death she smiled,
And the rose was full in blossom.

THE UNCOMMERCIAL TRAVELLER.

HAVING occasion to transact some business with a solicitor who occupies a highly suicidal set of chambers in Gray's Inn, I afterwards took a turn in the large square of that stronghold of Melancholy, reviewing, with congenial surroundings, my experiences of Chambers.

I began, as was natural, with the Chambers I had just left. They were an upper set on a rotten staircase, with a very mysterious bunk or bulkhead on the landing outside them, of a rather nautical and Screw Collier-like appearance than otherwise, and painted an intense black. Many dusty years have passed, since the appropriation of this Davy Jones's locker to any purpose, and during the whole period within the memory of living man, it has been hasped and padlocked. I cannot quite satisfy my mind whether it was originally meant for the reception of coals, or bodies, or as a place of temporary security for the plunder "looted" by laundresses; but I incline to the last opinion. It is about breast-high, and usually serves as a bulk for defendants in reduced circumstances to lean against and ponder at, when they come on the hopeful errand of trying to make an arrangement without money-under

which auspicious circumstances it mostly happens ' that the legal gentleman they want to see, is much engaged, and they pervade the staircase for a considerable period. Against this opposing bulk, in the absurdest manner, the tomb-like outer door of the solicitor's chambers (which is also of an intense black) stands in dark ambush, half open and half shut, all day. The solicitor's apartments are three in number; consisting of a slice, a cell, and a wedge. The slice is assigned to the two clerks, the cell is occupied by the principal, and the wedge is devoted to stray papers, old game baskets from the country, a washing-stand, and a model of a patent Ship's Caboose which was exhibited in Chancery at the commencement of the present century on an application for an injunction to restrain infringement. At about half-past nine on every week-day morning, the younger of the two clerks (who, I have reason to believe, leads the fashion at Pentonville in the articles of pipes and shirts) may be found knocking the dust out of his official door-key on the bunk or locker before mentioned; and so exceedingly subject to dust is his key, and so very retentive of that superfluity, that in exceptional summer weather when a ray of sunlight has fallen on the locker in my presence, I have noticed its inexpressive countenance to be deeply marked by a kind of Bramah erysipelas or small-pox.

This set of chambers (as I have gradually discovered, when I have had restless occasion to make inquiries or leave messages, after office hours) is under the charge of a lady, in figure extremely like an old family-umbrella, named Sweeney: whose dwelling confronts a dead wall in a court off Gray's Inn-lane, and who is usually fetched into the passage of that bower, when wanted, from some neighbouring home of industry which has the curious property of imparting an inflammatory appearance to her visage. Mrs. Sweeney is one of the race of professed laundresses, and is the compiler of a remarkable manuscript volume entitled "Mrs. Sweeney's Book," from which much curious statistical information may be gathered respecting the high prices and small uses of soda, soap, sand, firewood, and other such articles. I have created a legend in my mind-and consequently I believe it with the utmost pertinacity-that the late Mr. Sweeney was a ticket-porter under the Honourable Society of Gray's Inn, and that, in consideration of his long and valuable services, Mrs. Sweeney was appointed to her present post. For, though devoid of personal charms, I have observed this lady to exercise a fascination over the elderly ticket-porter mind (particularly under the gateway, and in corners and entries), which I can only refer to her being one of the fraternity, yet not competing with it. All that need be said concerning this set of chambers, is said, when I have added that it is in a large double house in Gray's Inn-square, very much out of repair, and that the outer portal is ornamented in a hideous manner with certain stone remains, which have the appearance of the dismembered bust, torso, and limbs, of a petrified bencher.

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