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THE PALAZZO PITTI*, or DUCAL PALACE, so that, while, at Paris, every body has to walk on FLORENCE.

the carriage-road, at Florence, all the carriages seem Our engraving represents the Palace of Leopold, to be on the footpath. Here the carriages of the

gentry are numerous, and often splendid, even rivalof Florence, a point of much attraction to strangers ling those in London: they are chiefly brought from visiting that celebrated city. It is a good specimen Milan, a place noted for their manufacture. of the architecture of Florence, where the buildings sions of Florence are built, has been folle wed in more

The vast and massive style in which the old manare ancient and lofty, while its spacious palaces, modern days, now that there is no longer that need the remnant of flourishing periods, are of a stern and sombre appearance , but look strong in their old age. and jealousy burned between noble families, each

of defence which existed, when feelings of hatred In the construction of the Ducal Palace, for instance,

trying to gain the pre-eminence at the expense of we can trace, throughout, uncommon solidity, and a

a great neighbour; as if forgetting that one main plentiful use of rich materials, but an utter disdain

source of happiness is found in walking through this of every thing that is merely ornamental.

life as friends, and that the same common dust must FLORENCE (in Italian, Firenze, or Fiorenza,) con

soon cover them, and all their boasted pomp. tinues, in many respects, to answer to its name,

Arnolfo di Lapo, who flourished in 1290, and died which signifies The Flourishing. It is situated on

in 1330, was the builder of some of the larg both banks of the river Arno, nearly at the head

structures now remaining. At a time when Florence of the broad and fertile vale which stretches to

was at the height of her prosperity, he seems to have Pisa, and thence to the sea ; and the charming tract of country in which it stands, is called the led the way as an architect, and to have stamped Garden of Tuscany. The road along the banks of upon the city that air of sullen grandeur which it

has never lost, and which, at the first glance, fills the the river, between Pisa and Florence, presents a

mind with wonder. Such heavy and gloomy fabrics succession of fine and varied prospects

, greatly are certainly calculated to give a melancholy aspect depending, however, for their beauty, on the sea

to the place; but with so many objects of historical son; as the Arno, which crosses Florence, is, in

interest, and so many treasures of art on all sides, the heat of summer, a shallow and mean-looking and, withal, a cheerful and pretty large population, stream, flowing in the midst of a very broad bed, Florence is seldom accused of being dull. It has the and is at times

fordable; but, when swollen by rains, aspect of a city filled with nobles and their domestics; or the melting of the snow on the mountains, it

a city of bridges, churches, and palaces. Four becomes a wide and deep river. In the height of an Italian summer, also, travelling in the day is often Trinità, formed of three elliptie arches of white marble,

bridges cross the Arno, of which the Ponte della irksome and fatiguing, on account of the excessive is one of the most graceful bridges in the world; an heat; a circumstance which alone would take away exception, in point of lightness and elegance, to the from the enjoyment of any scenery, however lovely. Florence is, in form, nearly an oval, and contains Gallery is enriched with statues, busts, and paint

style prevailing around it. The famous Florentine a population of about 80,000 persons. Its delightful position, sheltered by hills, many of them well culti- ings, of the highest order of art, many of them

having been contributed by members of the splenvated, which again are overtopped by the snow-clad did family of Medici, with whom, indeed, this noble Apennines; the vineyards and olive-grounds in its neighbourhood; the various gems of art which it sides of an oblong square. To go into the details

museum had its origin. The building forms three contains, in pictures, statues, monuments, and noble here, or even to attempt a general account of its buildings; the cleanliness of the hotels, and the contents, would be vain. The principal treasures of mildness and civility of its inhabitants; all these the collection, however, are the statues and busts. advantages have obtained for Florence the title of the

From this Gallery (which stands on the north bank Athens of Italy," and render it an agreeable residence of the Arno,) a bridge leads to the Palazzo Pitti, on The number of foreigners living there is generally the south side, where the Grand Duke, as an absogreater than that in any other Italian city, with the lute sovereign, resides, and holds his court. This exception of Rome : among these are many English. palace, now called Palazzo Ducale, and commonly by It would give us pleasure, did our limits allow us, the English The Pirti PALACE, is supposed to have to dwell on the amiable points of character which been built by Luca Pitti, a Florentine merchant, most travellers agree in assigning to the Florentines: with the ambitious and foolish design of out-doing we mean their gentleness and courtesy to strangers, in magnificence the Medici family, the objects of his as well as their humane and charitable disposition to rivalry; but he nearly ruined himself by the exthe sick and distressed among their people. We might also touch upon their neat and musical Italian pense. It is a rude and simple pile, defective in its dialect. But we must return (for the illustration of size, an imposing effect, particularly fronting the

masonry, yet having, from its towering height and our print) to the city, its architecture, and its street. In the space opposite to it are seen statues, palaces, particularly the Palazzo Pitti, with its lofty larger than life, including the Hercules by Bandiand frowning tower.

nello, and the David by Michael Angelo. On going · Florence is greatly improved since Bishop Burnet's through the palace, the visiter finds that it forms time, when “not one window in ten had any glass three sides of a court, which has a fountain on the in it.” “But it was then in a low condition, owing to fourth ; behind this are the admired groves of the the decay of trade. More attention is now paid, in Boboli gardens. John Ray, the naturalist, who this, as well as in other towns on the continent, travelled over the continent in search of plants, and to what we English people call comfort, than was formerly

the case ; yet still, the streets are in general among other places, visited Florence in 1664, saysvery narrow, paved with large flag-stones, which are

I might spend many words in describing the Grand

Duke's palace, and gardens, stored with great variety of closely fitted to each other, with no line of difference trees and shrubs, valuable for shade, beauty, fruit, and between the foot-way and the carriage-road, and re- scent; adorned with a multitude of statues, thick set up mind an English traveller of broad alleys in London; and down the walks and knots; pleasant fountains and many of the palaces are made of great rough-hewn stones, | sary to erect some fortifications. Indistinct traces) not laid smooth, but projecting above the surface of the but of considerable extent, have been found at wall: which fashion of building is called The Rustic man.

water-works; stately and delicious walks, both close and * The Pirrı PALACE, so called after the name of its founder. open; goodly flowers and choice plants......... In Florence

South Shields, of Roman buildings; stones, with ner.

inscriptions upon them, occurring among the moThe garden-front of the palace has been much nastic ruins of Tynemouth, present a less certain blamed for the strange mixture of its architecture; evidence of that people having alsu resided there. but, we repeat that bulk and strength were the chief Whether Tynemouth was, or was not, of Roman aim in this and other fabrics, joined, however, with foundation, it was at a very early date selected as an much that is noble and elegant. In such palaces, in ecclesiastical site, for which the beauty and peculiformer days, the rulers, the noble, and the merchant, arity of its situation well adapted it

. A wooden dined together, surrounded by their family and the chapel was built there, in A.D. 625, by Edwin, King adherents of their party; their guests were seated in of Northumberland. No place, perhaps, in the the order in which they arrived. At the board of island, was more exposed to the devastations of Lorenzo the Magnificent, whose court was adorned the Danish pirates. From 625, to 1110, its hisby the most distinguished men of the age, as well in tory is that of alternate destruction and renovation literature and science, as in rank and wealth, Michael continually repeated. Long subsequent to the Angelo, and other great artists, were often seated Conquest, it was liable to Scottish incursions, and, next to himself; and, notwithstanding the occasional during the civil wars of the seventeenth century, it feuds which raged between certain great clans, there was frequently besieged. After that period, when existed a kindly feeling among the various classes of all danger might be supposed to have passed away, society, which, although Florence has passed the its extensive and exquisitely-beautiful ruins, were days of her political and commercial importance, almost demolished for the sake of their materials. seems still to continue, and to claim the notice of Much of the priory of Tynemouth, it is prostrangers.

bable, was built with the hewn stone from the RoThe apartments of the Pitti Palace are exceedingly man station at the Law, South Shields; and great elegant, and contain the best collection of pictures in part of the town of North Shields, in return, is said, Florence, we may add, perhaps, in the world. Many to be built from the ruins of the monastery. Dockof these were carried away by Napoleon Buonaparte, wray square in particular, is popularly spoken of, as when Italy was overrun by the French armies under having been constructed from this source,

Nor was his command, but they are now all restored: they this ait. Being used as a barrack and military store, are hung in rich frames, on dark green and crim- the work of demolition and alteration has been son velvet grounds: the ceilings of the rooms are gradually continued, down to a late period. The admirably painted in fresco.

most conspicuous part of the ruin now standing, The architect of the palace was Brunelleschi, who is the three very beautiful eastern windows of the flourished in 1420, and at that time became famous chapel, represented in the engraving* for erecting a large and extraordinary dome on the

Tynemouth stands upon a promontory of limeCathedral of Florence. This dome, or cupola, was

stone, rising perpendicularly from the sea to a very the admiration of Michael Angelo, who thought it a considerable height. At the eastern extremity of the triumph of skill; and it is said by some to have cliff, are the ruins of the priory, which, from their furnished the idea of that of St. Peter's, at Rome. great elevation, form a very conspicuous sea-mark: It has no columns to assist, no hidden buttresses to adjoining them, is an excellent light-house upon the shore it up, and is nearly fifty feet higher than the revolving principle. About an hundred yards west dome of St. Paul's, London. Of all the churches of of the monastic ruins, stands the castle, which is now Florence, the Cathedral is the first in size and transformed into a plain and unpicturesque building, ornament.

and fitted up as barracks for the accommodation of Almost every famịly of property in Florence pos

a corps of infantry, which, with some artillery, are sesses, at some distance from the town, a vineyard, always stationed there. Beyond the castle, lies the the surplus wine from which is disposed of in a very village of Tynemouth, composed chiefly of lodgingsingular manner. In the walls of their large and houses for the reception of bathers, who flock thither noble mansions, are holes large enough to admit a during the summer-months, from all the surrounding three-quart bottle, and persons, of whatever degree, neighbourhood, and particularly from Newcastle. call at any hour, and, knocking at the porch, thrust

The port of Newcastle is an object of some imin their vessels, with a certain sum of money, which portance in the nautical history of this country, are immediately returned, with a due quantity of wine. Until within the last few years, nearly all the coal This trade is not confined to persons of moderate consumed in London was shipped from it.

Newrank, but is a source of revenue even to counts and castle on Tyne, lies about ten miles from the mouth dukes.

of the river, and upon the northern or Northumbrian

bank. On the south side, in the county of Durham, THE RUINS OF TYNEMOUTH PRIORY. but connected with Newcastle by a substantial bridge, IN 120, A.D., the Romans, to protect their possessions is the newly-created borough of Gateshead, where the in this island from the incursions of the Picts and

cholera raged with peculiar virulence, in December, Scots, built a fortified wall across the narrowest and 1831, on its first appearance in this country. The most northern part of their dominions. This wall

banks of the river, on both sides, are edged by ran in a direct line, nearly from sea to .sea, through collieries, by pit-rows or colliery-villages, and by the present counties of Cumberland and Northum- staiths, or machines for shipping the coal, when berland. The eastern extremity of this fortification brought from any distance. Wallsend, mentioned beterminated at Segedunum, to this day called Wall's.

fore, and Howdon on the north, with Jarrow, formerly end, a station on the northern bank of the Tyne,

the residence of the venerable Bede, Hebburn, and about four miles from the mouth of the river. The Felling, whence the well-known Newcastle grindstones breadth of the river below this point, appears to * We are indebted to Mr. T. M. Richardson, of Newcastle, for have been considered by them as sufficient protection the drawing from which this engraving was made (as well as for for the short remainder of the distance; but at the

those of Warkworth castle, already given): and hope shortly to

furnish views of other interesting objects in the North of England, mouth, on one or both sides, they thought it neces- from drawings by the same able artist.


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are shipped, on the south, are the principal villag.s. | dious church, situated in the market-place; a chapel At the mouth of the river, on the north side, running containing 700 free sittings, was built in 1818, chiefly within half a mile of Tynemouth, on the south side at the expense of the Dean and Chapter of Durham, extending to the very edge of the sea, lie the two who are lords of the manor, and who are now towns of North and South Shields.

engaged in erecting another chapel. The term Shields, or Sheals, is of frequent occur- North Shields is a larger town, containing about rence in the north of England, in the names of 20,000 inhabitants. Not having, however, engaged places, and signifies, a small collection of huts or in trade, it did not become a place of any consepaltry buildings*. Both these towns are of consider- quence, previous to the time of Oliver Cromwell, able antiquity, but have only flourished within about who, by the removal of certain restrictions which a century. South Shields was, as is mentioned had been imposed by the corporation of Newcastle, above, a Roman station, and probably of no very enabled it to engage successfully in navigation. Its trifling importance, as the road Wrecken Dyke ran external appearance is much the same as that of from it. During the middle ages, it appears, how- South Shields. Like that place, its population is ever, to have sunk into entire insignificance. From chiefly dependent upon the sea, and upon the various this it emerged, owing to the establishment of the trades which are supported by the shipping. The salt-trade, towards the close of the fifteenth century. vessels in which the fuel of the metropolis was Salt was long the staple commodity of the place, and conveyed, belonged almost entirely, until within the Shields salt bears still a preference in the markets. last few years, to the port of Newcastle ; that is, to The process by which it was obtained, was by evapo- the towns on the Tyne. Besides collier-brigs, there ration from salt-water, exposed in shallow vessels is also a considerable trade to the Baltic and the termed Pans. Of these pans, not half a dozen are Canadas for timber, and several vessels are annually now in use; but at the close of the seventeenth fitted out for the Greenland fishery. During the late century, one hundred and fifty were in full activity. war, the ship-owners of this port carried on a very The town is divided into wards, still called, from lucrative connexion with government, by hiring out these manufactories, East-pan-ward, West-pan-ward, their vessels for the conveyance of troops or stores : &c. As the salt-trade declined, others rose, which | this was called the transport-service. more than compensated for the loss. Glass became The total present tonnage of the port is 211,148 a commodity, in the production of which South tons, employing 8444 men; of these, 69,744 tons Shields particularly excelled. Bottle-glass, crown belong to North Shields, affording, at the average of or window-glasst, and latterly, plate-glass, have been four men to the hundred tons, employment to 2789 made in this town in great quantities. The prin-, seamen : South Shields, in like manner, furnishes cipal support, however, of the place, has been, 67,980 tons, and 2719 men. and is, its shipping, and those trades principally The sailors from the Tyne will be famous so connected with shipping. The population of the long as European history is read, as having formed town is about 18,000; the houses are generally the principal equipment of those fleets, which, mean, though there is a good market-place and under Nelson, St. Vincent, Collingwood, and others, some respectable streets leading from it. The right raised the British flag to its proudest elevation. A of returning one member to Parliament, was given wreck which took place off the mouth of this river to it by the bill of 1832. It is in the county and some years ago, was the cause of the invention diocese of Durham. There is a large and commo- of the life-boat, a contrivance by which numerous The word Shielding is still applied in Scotland to such edifices. lives are now saved every year on all parts of + See Saturday Magazine, Vol. III. p. 132.

the British coast; and with a more detailed account


of which we hope soon to present our readers. instead of that, he never once showed me his books, but North Shields has been, since the recent Act, repre- kept me to such hard labour, that I was disabled, from sented by one member. It contains one church, the being overworked; and when my illness obliged me to leave presentation to which is alternately in the gift of because I had not completed my half-year's service. In

him, he would pay me nothing for my three nionths' labour, the Duke of Northumberland and of Sir Jacob

my weak state, I made a wooden watch and clock, and Astley, who possesses the property of the ancient other things, which I took, when I was recovered, to Sir family of Delaval, of Seaton Delaval.

James Dunbar, of Duru, who, I heard, was a good-natured gentleman; he received me very kindly, and by means of

this introduction, I was afterwards enabled to go to EdinEMINENCE FROM HUMBLE LIFE. burgh, and pursue my favourite studies, and also had the JAMES FERGUSON, who distinguished himself as pleasure of occasionally supplying the wants of my poor mathematician, mechanic, and astronomer, gives the follow

father. ing interesting account of his early life: I was born in James Ferguson, whose own account of his early life is the year 1710, a few miles from Keith, a little village in here given, became a Member of the Royal Society of Bamffshire, in the north of Scotland ; and can with plea- London, a 'celebrated lecturer on Astronomy and Natural sure say, that my parents, though poor, were religious and Philosophy, and the author of several scientific works. Lonest; lived in good repute with all who knew them, and Among the attendants on his lectures was the then Prince died with good characters. Though my father had nothing of Wales, afterwards George the Third, who settled upon to support a large family but his daily labour, and the profits Ferguson a pension of fifty pounds a year. He was a of a few acres of land which he rented, yet his children were man of plain and unassuming manners, and frugal habits, not neglected, for at his leisure hours, he taught them to and at his death, in 1776, was worth six thousand pounds. read and write; and it was while he was teaching my elder brother to read the Catechism, that I acquired

SUPPLEMENT TO my reading. Ashamed to ask my father to instruct me, I used, when alone, to study the lesson which he had been

GRAY'S ELEGY IN A COUNTRY CHURCH-YARD. teaching my brother; and in any difficulty, I went to a The celebrated Elegy in a Country Church-Yard, by Gray, is well neighbouring old woman, who gave me such help as known, and justly admired, by every one who has the lest pretenenabled me to agreeably surprise my father, when he

sions to taste. But with all its polish, and deep poetic beauty and

feeling, it always appeared to me to be defective, and I have met found me one day reading by myself, before he had

with a remark in Cecil's Remains, to the same effect. Amid a scene thought of teaching me: he, therefore, gave me further so well calculated to awaken in a pious mind reflections on the instruction, and taught me to write; which, with about sublime truths, and inspiring hopes of Christianity, Gray, with the three months I afterwards had at the grammar-school at

exception of two or three somewhat equivocal expressions, says Keith, was all the education I ever received.

scarcely a word which might not have been said by one who believed

that “ death was an eternal sleep," and who was disposed to regard My taste for mechanics arose from an odd accident.

the humble tenants of those tombs as indeed “each in his narrow When about seven or eight years of age, a part of the roof cell for ever laid." With these views I have regretted, that sentiof the house being decayed, my father, in repairing it, ap- ments similar to the following had not sprung up in the heart, and plied a prop and lever to an upright spar, to raise it to its received the exquisite touches of the classic pen of Gray. They former situation; and to my great astonishment, I saw him,

might, with great propriety, have followed the stanza, beginning without considering the reason, lift up the ponderous roof,

Far from the madding crowd's ignoble strife. as if it had been a small weight. I attributed this at first

No airy dreams their simple fancies fired, to a degree of strength that excited my terror as well as

No thirst for wealth, nor panting after fame; wonder ; but, thinking further of the matter, I recollected

But truth divine sublimer hopes inspired, that he had applied his strength to that end of the lever

And urged them onward to a nobler aim, which was farthest from the prop; and finding, on inquiry, From every cottage, with the day arose that this was the cause of the seeming wonder, I began

The hallowed voice of spirit-breathing prayer;

And artless anthems, at its peaceful close, making levers, (which I then called bars,) and tried dif

Like holy incense, charmed the evening air. ferent experiments with them, and with wheels, which I

Though they, each tome of human lore unknown, made with my father's turning-lathe and a little knife.

The brilliant path of science never trod, But, as my father could not afford to maintain me,

The Sacred Volume claimed their hearts alone, while I was in pursuit only of these matters, and I was too Which taught the way to glory and to God. young and weak for hard labour, he put me to a neighbour

Here they from truth's eternal fountain drew, to keep sheep, and then I began to observe the stars by

The pure and gladdening waters day by day; night, fixing their places on a string with small beads on Learnt, since our days are evil, fleet, and few, it, and then marking them down on paper. I then went

To walk in wisdon's bright and peaceful way. to serve a considerable farmer, whose name was James In yon lone pile, o'er which hath sternly pass'd Glashan ; when he saw me, after my work was done, go The heavy hand of all-destroying Time, into a field, with a blanket about me, and lie on my back

Through whose low-mouldering aisles now sighs the blast,

And round whose altars grass and ivy climb:. to observe the stars, he at first laughed at me, but, when I

They gladly thronged, their grateful hymns to raise, explained my meaning to him, he encouraged me to go on,

Oft as the calm and holy Sabbath shone; and that I might make fair copies in the day-time of what

The mingled tribute of their prayers and praise, I had done in the night, he often worked for me himself,

In sweet communion rose before the Throne. taking the threshing-flail out of my hand, while I sat by

Ilere, from tnose honoured lips, which sacred fire him in the barn, busy with my compasses and pen. I shall

From Heaven's high chancery hath touched, they hear always have a respect for the memory of that man.

Truths which their zeal inflame, their hopes inspire,
At this time, a gentleman, Thomas Grant, Esq., of Give wings to faith, and check affliction's tear.
Achoynancy, happening to see one of my plans, asked me to When life flowed by, and, like an angel, Death
go to his house, as his butler could give me a great deal of

Came to release them to the world on high,

Praise trembled still on each expiring breath, ; instruction. I would not leave my good master till my time

And holy triumph beamed from every eye. was out; but I then went to Squire Grant's, where the butler, Alexander Cantley, soon became my friend, and

Then gentle hands their “dust to dust” consign;

With quiet tears, the simple rites are said, continued so till his death. He was an extraordinary

And here they sleep, till at the trump divine, man,-a complete master of arithmetic, a good mathemati

The earth and ocean render up their dead. cian, a master of music, understood Latin, French, and

[FROM AN AMERICAN WRITER.] Greek, and could even prescribe as a physician upon an urgent occasion.

When I returned home, I could not think of being a So completely is the ground impregnated with seeds, that burden to my father, so I went to a miller, thinking I if earth is brought to the surface from the lowest depth at should have plenty of time for my studies; but my master which it is found, some vegetable matter will spring from was so fond of the ale-house, that the whole care of the mill it. In boring for water lately, at a spot near Kingston-onwas left to me, and I was so nearly starved, that I was Thames, some earth was brought up from a depth of 360 glad when I could get a little oatmeal mixed with water feet; this earth was carefully covered over with a hanuto eat. When my year's engagement with this, man was glass, to prevent the possibility of other seeds being over, I went to a larmer, who practised as a physician, and deposited upon it, yet, in a short time, plants vegetated who promised to teach me that part of his business, but | froin it.---JESSE.

Miles an Hour

Difference of Diurnal Motion in

Miles an Hour.


Motion on her Axis.





FAMILIAR ILLUSTRATIONS OF NATURAL the circumference of the earth at the equator is about PHENOMENA

24,000 miles*, a place on the equator is carried round No. VII. THE TRADE WINDS.

at the rate of about 1000 miles an hour; but any place In our own climate, the uncertainty of the wind has north or south of the equator, does not move so fast, almost become a proverb. But we can yet see, that for it will plainly move through a less circle in the there are some general rules by which the currents same time. Thus, a place very near the Poles of the air seem to be governed. Taking the average scarcely moves at all; a place in the latitude of 60°, of the whole year, the wind blows much more fre- as at the Shetland Isles, moves only half as fast as at quently from the westerly quarter of the heavens the equator, or at the rate of 500 miles an hour ; a than from the east ; but there are several weeks in place in the latitude of 30°, as at Cairo, in Egypt, the spring, and in the early part of the summer, when moves at the rate of 866 miles an hour; and as we easterly winds prevail. These effects are far too con

advance towards the equator, the motion of the parts stant to arise without some fixed cause; and it is to

of the earth's surface continually increases, as is be regretted, that we do not yet know enough of the

shown in the table below, which is given by Capt. Hall. course and force of the winds, to discover what all Degrees of

by the Earth's daily those causes are. But, in other parts of the world, especially between

90° (Pole)

0 80

174 the tropics, the winds blow with much greater regu

174 70

168 larity. Their direction can be calculated upon with

158 such a degree of certainty, as to render them of the


143 utmost importance to navigation; hence these stated


123 currents of the air are called the Trade Winds.

100 The general phenomena are of this nature. Between 20

74 10

45 the tropics, the tendency of the wind is from the

. 1000

15 eastward towards the west.

0 (The Equator). To the north of the Equator, the wind blows from about N.E. to S.W.; If a current of air is passing from the Poles and, to the south of the Equator, it blows from about to the Equator over the surface of the earth, it is S.E. to N.W. From some little distance, on either carried continually from parts which are moving side of the Equator itself, there is no regular wind. from West to East, with less rapidity, into those There are usually baffling calms, accompanied with which are moving with a greater rapidity. With occasional violent storms.

reference, then, to the surface of the earth, the The cause of the Trade Winds is very simple. current which is passing from the Northern regions They arise from the currents of cold air setting from towards the Equator, will be affected with two the Poles towards the Equator, combined with the motions, one from North to South, arising from motion of the earth itself upon its axis. It is easy the actual motion of the air, the other from East to to see, that the action of the heat of the sun has a West, arising from the greater motion of the surface constant tendency to cause currents in the air. When of the earth itself from West to East. The conseair is heated, it becomes lighter than it was before ; quence of those two motions will be the production and any one may satisfy himself, that a current will of an oblique motion, in a direction between the two : be produced, when hotter and colder air communi- or there will be perceived a wind blowing from about cate with each other, by holding a candle at the the N.E. quarter. In like manner, the southerly bottom and at the top of an open door, which com- current of air flowing from the South Pole towards municates between a warm room and a cold passage; the Equator will be changed, as it advances, into he will see that the warm air is running out at the a current which comes from the South-easterly top, while the cold air is running in at the bottom. quarter, relatively to the surface of the earth.

Supposing, then, the whole earth to be at rest, and As these currents advance, it is plain that the to be heated in the regions about the Equator much constant friction of the air, upon the surface of the more than about the Poles, the air, at the earth's earth, tends to give the air the same motion which surface at the equator, being heated, would rise, and the earth has, and that, in proportion as that effect flow at the top of the atmosphere from the equator is produced, the rapidity of the relative easterly towards each pole, while the colder air of the poles current slackens. The air gradually acquires the would flow, at the bottom of the atmosphere, from motion of the part of the earth with which it is in the poles towards the equator, and thus a constant contact, moves on with it, and becomes relatively at change of air would take place. On the surface of rest. The above table, given by Captain Hall, the earth there would be a constant northerly wind will also show that the difference in the rapidity of in the parts to the north of the equator, and a con- motion of two points at a given distance from one stant southerly wind in the parts to the south of the another measured along any meridian, decreases raequator ; but, near the equator itself, there would be pidly near the Equator, so that, as the air approaches a calm, the currents from North and South balancing the Equator, the friction of the surface has a longer each other, and the air there ascending continually time to act upon the current of air, coming from the from the surface to the higher parts of the atmo- Poles, and is more effective. sphere. Local causes will prevent the currents from Hence we might expect, as it is found, that the the North and South Poles from neutralizing each apparent easterly Trade Wind would become weaker other exactly on the equator. In the Atlantic Ocean, near the Equator itself: and, as we have already the region of calms and baffling winds thus occa- seen, the two northerly and southerly currents also, sioned, is always to the north of the equator, and its in a great measure, counterbalance each other at the position varies at different periods of the year. Equator. The great regular causes of a Trade Wind

Such currents are continually taking place; but being thus checked, there will be, near the Equator, the direction of these currents, as observed at the a belt of calms, or baffling and uncertain winds, while surface of the earth, will be very materially altered to the North and South there will be a more settled in consequence of the motion of the earth itself.

current tending upon the whole from East to West. The earth turns round its axis once in twenty-four In the upper regions of the atmosphere, effects of hours, in a direction from West to East; and, since

* Accurately, 24,899 miles.

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