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My spring has swift flitted, my summer is past,
And autumn is yielding to winter's chill storm;
May this fast-flagging wing find a selter at last,
Where no whirlwinds the halcyon noontide deforın.
And find it I shall; for there waiteth a rest-

So uttered the High One; whose word may not fail;1 shall find it where, deathless, hope's long-sought behest Shall not hang by a thread, or be whirled by the gale. The Oriole builds her a pensile cot;

And pensile on earth be each hope or fear; Rejoicing as though I rejoiced not,

And weeping as though unbedimmed by a tear.

But the cagle repairs to the lofty rock;

Serene are the skies where she plumeth her wing; And I too would build where no tempests can shockI would build in the land of perpetual spring.

FAMILIAR ILLUSTRATIONS OF NATURAL PHENOMENA.

No. X. DEW.

THERE is scarcely a more beautiful sight in nature than that which is presented in a clear autumn morning, soon after sun-rise. Every leaf and spray is united by the light tissue of the gossamer-spider's web, on which are threaded beads of transparent water, glittering in the beams of the rising sun. Every blade of grass is, in like manner, enveloped in a fine coating of moisture, and spangled with brilliant drops. On an attentive observation, it will be found that the light, which passes through these minute globes of water, is separated into distinct colours. Spots of vivid red, yellow, and blue, will be perceived scattered, apparently at random, over the glistening surface, and, in some favourable points of view, there may be traced upon the plain an iris, composed of the same colours as the rainbow, and in the same order, but arranged in two branches receding from the eye.

The copious deposition of moisture, which produces this splendid spectacle, may have been occasioned by various causes. Fine rain may have fallen, or there may have been a sensible mist, or a thick fog. But, in many instances, the atmosphere will have appeared perfectly clear during the whole preceding night, and all the brilliant display will have been caused solely by the dew.

We propose to show in what manner the dew is deposited. It is a very common error to suppose, that the dew falls in the same manner as rain or mist, only in much finer particles. A very slight observation will show that dew is not thus formed; for it is often deposited on the sides, and on the under part of blades of grass and other substances, as well as on their upper surfaces.

Dew, in fact, does not fall, but is formed by the condensation of the moisture of the atmosphere. Every one is familiar with this phenomenon, though many may not have thought much about the cause of it. If we bring a bottle from a cool cellar in the summer, a copious deposition of dew takes place upon its outer surface. If a sudden hail-storm drives against the windows, a dew is often deposited upon the inner surface. In these and the like instances, the surface exposed to the air is colder than the air itself.

And since it is found that heat always passes from a hotter body to one that is colder, the invisible vapour of water in the atmosphere immediately in contact with the glass, loses part of the heat, which is necessary in order to keep it in the state of vapour, and is condensed, or reduced to the form of water.

The moisture begins to be thus precipitated at a certain temperature, depending upon the quantity of vapour in the atmosphere. This temperature is called the dew-point.

But heat is given out from one body to another,

not only when they are close together, but when they are at great distances from each other. Without at all attempting to show what heat is, or how it is communicated from one body to another, it is sufficient for our present purpose to know, that there is a constant tendency in all bodies towards an equality of temperature; so that if there be two bodies heated to different degrees, the heat of that which is the hotter is given out, and increases the heat of the colder body. If the bodies are in contact, the heat is said to be communicated by conduction; if they are not in contact, the heat is said to be radiated from one body to another.

When, for instance, we are standing before a fire in a cold day, the heat of the fire is so much greater than that of the human body, that we are sensible of a great radiation of heat from the fire. But if a person comes suddenly into the room from the frosty atmosphere, we are sensible that he strikes cold; that is, that the heat given out by radiation from our bodies to his, is greater than that which we receive in return.

By means of a delicate thermometer, the radiation of heat is made very perceptible: and different bodies are found to radiate heat with greater or less readiness. Among those which radiate heat rapidly, are glass, wool, the blades of grass, cotton, &c.

Hence, every object in nature is constantly radiating heat from its surface. If a body be surrounded by objects which are hotter than itself, it becomes heated by radiation: if it be exposed to the influence of objects which are colder than itself, it becomes cooled: and its temperature will not be sensibly altered, if the bodies around it have nearly the same temperature as itself. If, also, a body be formed of a substance which conducts heat badly, but radiates heat easily, the extremities of such a body, when exposed to other cooler bodies, will lose heat by radiation faster than it can be replaced by conduction, and will become colder than the other parts of the bodies.

Suppose, now, an extensive plain, partly covered with grass, and exposed to the atmosphere in a serene night. If the sky be overclouded, the heat radiated from all the objects in the plain, will be so nearly equal to that which is radiated from the clouds, that the surface of the plain will cool very slowly. But if the clouds clear away, the heat which is radiated from the plain, passes off into the open space of the heavens, and so little is radiated back, that the process of cooling goes on with great rapidity. In those parts of the plain which are covered with sand, or stone, or other substances which conduct heat well, the heat which is radiated from the surface, is speedily restored in part, by heat passing along the body from the interior, and the surface cools more slowly. But this is not the case with the blades of grass, or with any flocky substance, such as wool, cobwebs, and the like. These substances radiate heat rapidly, but conduct it badly. Hence, their surfaces become speedily cool; and as soon as they are cooled down to the temperature of the dew-point, the moisture of the air is condensed upon them, or there is a dew. If the radiation of heat still continues, the temperature of those surfaces may be still further lowered, even to the freezing point; and then the deposition takes the beautiful form of hoar-frost.

In order, then, that dew may be deposited, the following circumstances must conspire:

1. The sun must be absent, or, at least, must be very near the horizon.

2. The atmosphere must be nearly calin: whence

the Spanish name of dew is Serena, indicating the serenity of the sky when it is most copiously deposited *. 3. The sky must be free from clouds.

4. The substances, on which the dew is deposited, must be freely exposed to the action of the sky, and

must be of such a nature, as to radiate heat easily, and to conduct it with difficulty.

Dr. Wells, in his beautiful and philosophical Essay on Dew, published in 1814, was the first person who fully explained all the circumstances connected with this interesting natural phenomenon. C.

* Hence is derived the word "Serenade."

WE sometimes saw a blue line suddenly drawn across a field of pure white, then another above it, and another, all parallel, and attended each time, with a loud crash like cannon, producing together, the effect of long-protracted peals of thunder. At other times, some portion of the vast field of snow, or rather snowy ice, gliding gently away, exposed to view a new surface, of purer white than the first, and the cast-off drapery gathering in long folds, either fell at once down the precipice, or disappeared behind some intervening ridge, which the sameness of colour rendered invisible, and was again seen soon after, in another direction, shooting out of some narrow channel, a cataract of white dust, which, observed through a telescope, was, however, found to be composed of broken fragments of ice or compact snow, many of them sufficient to overwhelm a village, if there had been any in the valley where they fell. I must own, that while we shut our ears, the mere sight might dwindle down to the effect of a fall of snow from the roof of a house; but when the potent sound was heard, along the whole range of many miles, when the time of awful suspense, between the fall and the crash was measured, the imagination taking flight, outstripped all bounds at once, and went beyond the mighty reality itself.-SIMOND's Switzerland.

THERE is nothing more striking in the Malayan forests, than the grandeur of the vegetation! The magnitude of the flowers, creepers and trees, contrasts strikingly with the stunted and, I had almost said, pigmy vegetation of England. Compared with our forest-trees, your largest oak is a mere dwarf. Here, we have creepers and vines, entwining larger trees, and hanging suspended for more than a hundred feet, in girth not less than a man's body, and many much thicker; the trees seldom under a hundred, and generally approaching a hundred and sixty, to two hundred feet in height. One tree that we measured, was, in circumference, nine yards! and this is nothing to one I measured in Java.-SIR STAMFORD RAFFLES.

A CIRCUMSTANCE occurred here, (Cawoor,) which marks the superstitious fears of the natives. The coolies, (or porters,) in passing through the forest, came upon a tiger, crouched on the path; they immediately stopped, and addressed him in terms of supplication, assuring him, they were poor people, carrying the Tuan Basar, great man's luggage, who would be very angry with them, if they did not arrive in time, and, therefore, they implored permission to pass quietly, and without molestation. The tiger, being startled at their appearance, got up, and walked quietly into the depths of the forest; and they came on, perfectly satisfied' that it was in consequence of their petition, that they passed in safety.-LADY RAFFLES'S Journey in Sumatra.

THE King of the Island Toobow, is himself a Christian. This personage came on board, and paid the captain a visit. While on board, he unconsciously conveyed a severe practical reproof to certain persons, in the following manner. He sat down at the captain's table to partake of some refreshment, and though he was helped, paused ere he began to eat, and on his being asked why he did not begin, he replied, that he was waiting to say grace; (for this had been omitted on the present occasion, as it too frequently is.) However, the captain and the rest immediately arose, somewhat ashamed at being thus put to the blush, by one, whom they doubtless considered as infinitely their inferior in intellectual qualities. Upon which the king arose very seriously, and gave thanks, previous to commencing his repast.-Extract from a Letter, dated Tongataboo, Friendly Islands, May 27, 1833.

THE WELLINGTON SHIELD. No. III. THE REPULSE OF THE FRENCH AT VIMIERA.

It was towards the close of the year 1807, that

Buonaparte and the then King of Spain agreed to

unite in seizing the kingdom of Portugal, and arranged a plan for the partition of the whole territory under the Portuguese dominion.

Before the end of that year, a body of French troops, under General Junot, had marched through Spain, and taken possession of Lisbon; while a Spanish army had invaded Portugal, north and south. But the court of Spain soon began to repent of having joined in this nefarious project, and to suspect the sincerity of its wily ally; for Napoleon, taking advantage of the dissensions that raged among the Royal Family, amused and cajoled King Charles and his son Ferdinand, and keeping both parties in alarm and suspense, succeeded in marching his armies into Spain, and obtaining hold of the principal frontier fortresses, under the pretence of supporting his troops that were in Portugal. The French soon afterwards entered Madrid, and Buonaparte, contriving to inveigle both Charles and Ferdinand into his power at Bayonne, caused them to renounce all claims upon the throne of Spain in his favour. The Spanish people, justly indignant at these proceedings, took up arms against the French, and applied to England for assistance, which was instantly given. Arms and ammunition, money and clothing, were forwarded to them; and a body of 9000 troops, which happened to be assembled at Cork, was placed under the command of Lieutenant-General Sir Arthur Wellesley, and directed towards the Peninsula.

The British troops sailed from Cork on the 12th of July, 1808, and soon afterwards arrived off the coast of Portugal. They began to disembark on the 1st of August, but the operation was so difficult, that it was not completed until the 5th; and on that day, General Spencer arrived from Gibraltar, bringing with him a reinforcement, which swelled their numbers to 12,300 men. Junot quickly heard of their arrival, and was greatly embarrassed on account of the scattered state of his army. General Laborde, justly reputed to be one of the ablest of the French generals, was despatched from Lisbon with 3000 infantry, 500 or 600 cavalry, and five pieces of artillery, and directed to advance towards Leria; while General Loison, with between 7000 and 8000 men, was directed to effect a junction with Laborde.

The rapidity of the British general's movements completely destroyed this arrangement. Before either Loison or Laborde could reach Leria, the British had already taken possession of it; the line of communication between those generals was thus cut, and as their junction could only now be effected by a circuitous route, Laborde was exposed to be attacked alone, by an enemy who more than doubled him in numbers. Sir Arthur Wellesley availed himself of the advantage, and moving briskly on, came up with Laborde at Roliça. The French were attacked, and driven successively from two strong positions, which their able general had most skilfully selected, and which he defended in a most brave and soldierlike manner. They retired along the road leading to Torres Vedras, but Sir Arthur was prevented from pursuing them, because that movement would have led him away from the sea; and it was necessary for him to remain near the coast, in order to cover the landing of some reinforcements which had just arrived. On the 20th, the whole army was re-organised, and preparation made for resuming offensive operations on the morrow. But at this critical

moment, Sir Arthur was superseded in the chief | command of the army; and his successor, Sir Harry Burrard, did not deem it prudent to venture upon any offensive movement, until some reinforcements, which were expected under Sir John Moore, should arrive, and the whole army be concentrated.

In the mean while, Junot was not idle; leaving a sufficient force in Lisbon, and the forts on the Tagus, he quitted that city on the 15th, with a reserve of 2000 infantry, 600 cavalry, and 10 pieces of artillery, carrying with him, also, his grand park of ammunition, and a military chest containing one million of francs. Pushing forward himself to Alcoentre, he there found Loison, who was trying to re-establish his communication with Laborde. That general had reached Santarem on the 13th, in a deplorable condition. The weather had been intensely hot, without a cloud in the sky, or a breath of air stirring. Whole companies had lain down upon the way; many died of thirst, and more would have perished, if the officers of the staff, as soon as they arrived at that city, had not gone out with a great number of the inhabitants, carrying water and brandy to refresh them, and carts to convey those who were unable to proceed further on foot. Each of Loison's long marches at this time, is said to have cost him not less than an hundred men; and his troops were so dreadfully exhausted, that he was compelled to remain two days at Santarem. At length, by the 20th, Junot had assembled his whole force at Torres Vedras, in number about 14,000 men; and then reorganizing his army, he began to prepare for a decisive battle.

other, under Generals Brennier and Solignac, directed against the British left, partly upon its front, and partly upon its flank.

Loison's men came on boldly, and with the characteristic impetuosity of French troops. They forced in the skirmishers at once, but were received with a sharp discharge of musketry. Some close and heavy firing ensued, and the order was then given to use the bayonet. The enemy 66 came to the charge bravely," says Mr. Southey, "and stood it for a moment;" in that moment their foremost rank fell "like a line of grass before the mowers." This is not the flourish of an historian, seeking artfully to embellish details which no art can render interesting to any but military readers; it is the language of an actor in the scene, who could not call it to mind in after-hours without shuddering; for the very men, whose superiority was thus decidedly proved, could not speak without involuntary awe, of so complete and instantaneous a destruction, produced as it was, not by artillery or explosions, but by their own act and deed, and the strength of their own hearts and hands."

Simultaneously with Loison's attack, a dense column of 2000 men, led by Laborde, and preceded by a cloud of light troops, advanced towards the opposing lines; the British artillery, from the height on which they were posted, opened a terrible fire, and shattered them much; yet the French, notwithstanding, came on like good soldiers, and driving in the English skirmishers, quickly made their way to the summit of the hill. But here they were met by the 50th regiment, which, first pouring in a deadly volley among the thick masses, then charged them front and flank with the bayonet, and drove them back confusedly. Loison's attack had been, at the same time, repulsed; and Colonel Taylor, seizing the opportunity, burst in with his handful of dragoons, among the retreating masses, and pursued them to a considerable distance, with much slaughter. But Margaron soon espied the weakness of this gallant and devoted band; and galloping down upon them fiercely with his horsemen, slew the colonel, and cut half of the men to pieces. Kellerman now brought his reserve into action; a part was employed to cover the retreat of the beaten troops, while the other moved vigorously to attack the extreme left of the British centre, which occupied a church and church

The ground occupied by the British at Vimiera, had been taken up merely as a temporary position, and without any expectation on their part, of being called upon to fight a battle there. The village itself, situated in a beautiful valley, through which the little river Maceira flows, contained the park and commissariat stores; in front, arose a rugged isolated height, on which was posted the centre; the right rested on a mountain that swept in a half-circle from the village to the sea-coast, and the left, which was composed merely of a few piquets, occupied another mountain, extending from the opposite side of the village. On the morning of the 21st, about seven o'clock, a cloud of dust was observed beyond the nearest hills, and soon an advanced guard of horse, was seen to crown the heights to the south-yard that blocked the road leading over the height to ward, and to send forward scouts on every side. Presently, columns of infantry began to move successively along the road leading to Lourinham; and as they passed by, in front of the British centre, it became evident that a battle was their object, and that too, on the left of the British, which Junot had rightly judged to be weak. Sir Arthur quickly saw their plan, and he promptly met it, by moving a strong force from his right to support his left. The route of these troops lay across the valley behind the village, and their passage being quite screened by the high hill in its front, was thus unknown to Junot, who afterwards, to his surprise, found a powerful front of battle, where he had expected only a weak flank. The French army consisted of two divisions of infantry, under Loison and Laborde respectively, a third under Kellerman, which was composed of grenadiers, and kept as a reserve, and a fourth, of cavalry, under General Margaron; together with 23 pieces of artillery.

About ten o'clock the French began the fight. The divisions of Loison and Laborde, advanced in two separate attacks, the one headed by those Generals in person, against the British centre; the

the village. Towards this spot the 43rd regiment was engaged in a hot skirmish among some vineyards, with a part of Laborde's division. "The grenadiers coming on at a brisk pace," says Colonel Napier, "beat back the advanced companies of the 43rd; but to avoid the artillery that swept their left, they dipped a little into the ravine, and were taken on the other flank by the guns of the eighth and fourth brigades, and at the same time, the 43rd, rallying in a mass, broke down upon the head of the column at a moment when the narrowness of the way, and the discharges of the artillery, had somewhat disordered its formation; a short yet desperate fight took place; the enemy was repulsed in disorder, but the regiment suffered severely."

All the enemy's attempts upon the British centre were now entirely defeated. In the mean while, General Brennier had marched against the left. But coming unexpectedly upon a ravine, which protected its front, and of the existence of which he had previously been ignorant, he got entangled among the rocks and watercourses. Solignac, leading his men round, beyond the end of this ravine, reached the extremity of the mountain on which the English

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cavalry, and their entire force was brought into
action. Most of the wounded French, who fell into
the conquerors' hands, were young and of delicate
appearance, "apparently men,
apparently men," says Mr. Southey,
"whose lot would not have fallen in the army, under
any other system than that of the conscription,
though, having been forced into it, they had acquired
the worst vices which have ever disgraced and de-
graded the profession of arms." Yet even in this
piteous state, these unhappy youths would fain
rejoice in their sufferings, and fully betrayed that
ardent and insatiable thirst for military glory which
has ever been characteristic of their countrymen, and
which Napoleon so well knew how to foster, and to
turn to a profitable account, in the prosecution of his
own ambitious schemes. To one of them, a chaplain
of the British army happened to address himself in
the language of commiseration, uttering at the same
time, a Christian expression of regret at the horrors
of war: but the Frenchman fiercely answered, with a
mixture of pride and indignation, that he gloried in
his wounds, and that war was the greatest happiness
of life!*

left was posted, thinking to fall upon their flank. But he found a strong force there, which instantly bore down upon him, and spreading out as the ridge on which it moved widened, drove him quickly back. Solignac himself was carried from the field, severely wounded; six of his guns were captured, and leaving two regiments to guard them, the English general (Ferguson) pressed sharply forward upon the disordered columns of the French. At this moment, Brennier extricated himself from the ravine, and for an instant surprising those two regiments, retook the guns; but the British quickly rallied, and recovering the artillery, overthrew their assailants, and made Brennier himself prisoner. He was immediately carried to Sir Arthur Wellesley, and he eagerly asked, if the reserve under Kellerman had yet charged; Sir Arthur having previously learnt that it had, was now satisfied that all the enemy's efforts were exhausted. He at once saw the advantage of following up the victory, and resolved, while his left pressed Junot, to march the rest of his army towards Lisbon, and so cut the French off from that city. But Sir Harry Burrard, who was now commander, and who had been present during the action, although he had abstained from interfering with Sir Arthur Wellesley's arrangements, did not approve of the plan; weighing all the circumstances of the case, the bad state of his artillery-carriages, the want of "HE that loses his conscience, has nothing left that is draft horses, the confusion of his commissariat, and worth keeping." Therefore be sure you look to that. And the destruction of his cavalry, he thought the proin the next place look to your health: and if you have it, posal perilous. By his orders, all offensive opera-health is the second blessing that we mortals are capable praise God, and value it next to a good conscience; for tions were stopped, until the arrival of Sir John Moore, of, a blessing that money cannot buy, therefore value it, with the expected reinforcements. and be thankful for it.-IZAAK WALTON.

The loss of the French in this action was severe, and amounted to between 2000 and 3000 men. Their dead lay thickly strewn around; and they left 13 guns, and 23 ammunition waggons, in the hands of the victors. The English loss amounted to little more than 700 killed, wounded, and missing. Their numbers in the field before the action were 16,000, of which not more than one half had been engaged; the French were about 14,000, including 1300

• We beg, once for all, to express our obligation, in this and succeeding papers of the series, to the invaluable Histories of the Peninsular War, by the two great standard writers upon the subject, SOUTHEY and NAPIER.

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