« ΠροηγούμενηΣυνέχεια »
THEORY AND PRACTICE OF TEACHING.
thing for the child if he can be early made to feel that he is living to some purpose.
IV. A Dtsiue To uo Right. This, in other words, is a disposition to obey conscience by conforming to the will of God. This indeed is the hiirhest and holiest of all the motives to human action. In its fullest sense it constitutes the fundamental principle of a religious character. The teacher should most assiduously cultivate in the child a regard for this principle. God has implanted the conscience in every child of earth, that it should early be made use of to regulate the conduct. That teacher is either grossly ignorant or madly perverse, who disregards the conscience, while ha appeals alone to the selfishness of the young, and thus practically teaches that moral obligation is a nullity; that the law of God —so beautifully expounded by the Saviour—"Thou shalt love the Lord thy God with all thy heart, and with all thy soul, and with all thy mind," and "Thou shalt love thy neighbour as thyself"—is of little consequence; and that the injunction of the apostle — " Whether ye eat or drink, or whatsoever ye do, do all to the glory of God," is as good as obsolete.
In early childhood the conscience is most active. It needs, to be sure, at that period to be enlightened; but if the teachings of Revelation are made plain to the child, he seldom disregards them. The teacher has at this period very much to do, as we have before said under the head of the Responsibility of Teachers; and he cannot neglect his duty without the most aggravated culpability. The point we urge here is, that he should use these motives as incentives to study. The child can be made to feel that he owes the most diligent efforts for improvment to his teacher, who daily labours for his improvement; to his parents, who have kindly supplied his wants, and have provided the means for his cultivation; to society, ■whose privileges he may enjoy, and to which he is bound to make a return by becoming an intelligent and useful member of it; to himself, as a rational and immortal being, capable of unbounded enjoyment or untold misery, just in proportion as he prepares himself for either; and abpve all to his Creator, by whose bounty he lives, surrounded with friends and blessed with opportunities, which are denied to millions of his fellowbeings,—by whose gracious providence he has been endowed with faculties and capabilities making him but little lower than the angels, and which he is bound to cultivate for usefulness and for heaven,—by whose mercy he has been supplied, as millions have not, with the word of God, to guide his mind to things above, and with the influences of Christian society, to cheer him in his path to heaven;—above all, we repeat, should the child be taught to feel that he owes to God his best efforts to make the most of all his powers for time and eternity. If this can be done (and we believe to a great extent it can be done), there will be no need of a resort to those questionable incentives found in exciting children to outstrip their fellows by prizes and rewards; while in this very process the foundation of a good moral training will be laid, without which the perfect structure of a noble character can never be reared in later life.
To the motives already alluded to, if it be necessary to add another, we would urge.
V. The Pleasure Of Acquisition. This is often underrated by teachers. Our Creator has not more universally bestowed a natural appetite for the food which is necessary for the growth of the body, than he has a mental longing for the food of the mind; and as he has superadded a sensation of pleasure to the necessary act of eating, so he has made it a law of the mind to experience its highest delight while in the act of receiving the mental aliment. Whoever has observed childhood with an attentive eye, must huve been impressed with the wisdom of God in this arrangement. How much the child acquires within the first three years aftar its birth! He learns a difficult language with more precision than a welleducated adult foreigner could learn it in the same time; yet language is not his only or his chief study. During these same three years, he makes surprising advances in general knowledge. He seeks an intimate acquaintance with all the physical objects by which he is surrounded. The size, form, colour, weight, temperature, and use of each are investigated by the test of his own senses or ascertained by innumerable inquiries. His ideas of height and distance, of light and heat,
of motion and velocity, of cause and effect, are all well defined, lie has made no mean attainments in morals. He comprehends the law of right and wrong, so that his decisions may well put to the blush his superiors in age; and unless grossly neglected, he has learned the duty of obedience to parents and reverence towards God. Now all this amazing progress has been made because of the irropressible curiosity with which God has endowed him, and the unspeakable delight he experiences in acquiring the knowledge vrhich gratifies it.
All must have noticed the delight with which the child grasps a new idea; but few have been able to describe it so eloquently as it is done by Mr. Mann. "Mark a child," says he, '• when a clear, well-defined, vivid conception seizes it. The whole nervous tissue vibrates. Every muscle leaps. Every joint plays. The face becomes auroral. The spirit flashes through the body like lightning through a cloud.
"Observe, too, the blind, the deaf, and the dumb. So strong is their inborn desire for knowledge,—such are the amazing attractive forces of their minds for it, that although the natural inlets, the eye and the ear, are closed, yet they will draw it inward through the solid walls and encasements of the body. If the eye be curtained with darkness, it will enter through the ear. If the ear be closed in silence, it will ascend along the nerves of touch. Every new idea that enters into the presence of the sovreign mind, carries offerings of delight with it to make its coming welcome. Indeed our Maker created us in blank ignorance, for the very purpose of giving us the boundless, endless pleasure of learning new things."
It is of course not to be expected that the same degree of pleasure will attend the learner in every acquisition as the novelty diminishes, and as he advances in age. The bodily appetite is less keen in after life than in childhood, so that the adult may never realize again to the full extent the delicious flavours which regaled him in his earliest years. Still there will ever be a delight in acquisition; and to carry our illustration a little further,—as the child is soonest cloyed whose stomach is surfeited with dainties, and stimulated with condiments, and pampered with sweetmeats, till his taste has lost its acumen, and digestion becomes a burden; Bo the mental appetite is soonest destroyed, when, under the unskilful teacher, it is overloaded with what it can neither digest nor disgorge. The mind may be surfeited; and then no wonder if it loaths even the wholesome aliment. Artificial stimulants, in the shape of prizes, and honours, and flattery, and fear, and shame, may have impaired its functions, so that it ceases to act except under their excitement. But all must see that these are unnatural conditions, superinduced by erroneous treatment. There is still a delight in acquisition, just as soon as the faculties are aroused to the effort; and the skilful teacher will strive to make up the mind to find this delight,—and if he understands his work, he will scarcely need a stronger incentive. If he understands the secret of giving just so much instruction as to excite tho learner's curiosity, and then to leave him to discover and acquire for himself, he will have no necessity to use any other means as stimulants to exertion.
To this might be added that irrepressible curiosity, that allpervading desire to know, which is found in the mind of every child. The mind, as if conscious of its high destiny, instinctively spreads its unfledged wings in pursuit of knowledge. This, with come children, is an all-sufficient stimulant to the most vigorous exertion. To this the teacher may safely appeal. Indeed, it is a convincing proof of the wisdom as well as the goodness of God, that this desire to know, as well as the delight of acquisition, are the most active at that early period of childhood, when a just appreciation of the utility of knowledge, and the higher motives already detailed, could scarcely find a lodgment in the tender mind. It seems to be, therefore, an indisputable dictate of our very nature, that both these principles should be early employed as incentives
If, then, the desire of the approval of parents and teachers,—, tlu desire of adtcmccment,—tlie de-fire to be useful, —and the d'.sire to do right, can be superadded to the natural love in tlie chila for acquisition and a nuiujral desire to know, there will, as we believe, be but little occasion to look further for incentives to exertion in the pupil; and we may venture to add, as a scholium to what has already been said, that the teacher who has nut yet learned to call into exercise these higner motives, and to rely for success mainly upon them, and who dares not abandon the system of exciting stimulants for fear of a failure, has yet much to learn as a true educator of the young.
It is not necessary that mnch space should be occupied in speaking of the importance of order in our schools. Everybody who has written or spoken on this subject, has conceded the necessity of obedience on the part of the pupil. "order Is Heaven's First Law;" and it is scarcely more essential to the harmony of heaven, than it is to the happiness and success of the school.
If such be the necessity of order in the school, then he ability to secure and maintain it is no mean part of the qualification of the good teacher. It is lamentable that so many fail in this particular; and yet this frequent failure can in most cases be traced to some defect in the constitutional temperament, or some deficiency in the mental or moral cultureof the teacher himself.
LESSONS IN READING AND ELOCUTION.
EXCELLENCE OF THE HOLY SCRIPTURES.
Is it bigotry to believe the sublime truths of the Gospel with full assurance of faith? I glory in such bigotry. I would not part with it for a thousand worlds. I congratulate the man who is possessed of it: for, amidst all the vicissitudes and calamities of the present state, that man enjoys an inexhaustible fund of consolation, of which it is not in the power of fortune to deprive him,
There is not a book on earth so favourable to all the kind, and all the sublime affections; or so unfriendly to hatred and persecution, to tyranny, to injustice, and every sort of malevolence, as the Gospel. It breathes nothing throughout, but mercy, benevolence, and peace.
Poetry is sublime, when it awakens in the mind any great and good affection, as piety or patriotism. This is one of the noblest effects of the art. The Pealms are remarkable, beyond all other writings, for their power of inspiring devout erriotioas. But it is not in this respect only that they are sublime. Of the divine nature, they contain the most magnificent descriptions that the soul of man can comprehend. The hundred-and-fourth Psalm, in particular, displays the power and goodness of Providence, in creating and preserving the world, and the various tribes of animals in it, with such majestic brevity and beauty, as it is vain to look for in any human composition.
1 Such of the doctrines of the Gospel as are level to human capacity, appear to be agreeable to the purest truth and the soundest morality. All the genius and learning of the heathen world—all the penetration of Pythagoras, Socrates, and Aristotle, had never been able to produce such a system of moral duty, and so rational an account of Providence and of man, as are to be found in the New Testament. Compared, indeed, vim this, all other moral and theological wisdom
Lose9, discountenanced, and like folly shows.
I looked upon his brow,—no sign
Of guilt or fear was there; He stood as proud by that death-shrine.
As even o'er despair He had a power; in his eye There was a quenchless energy, H A spirit that could dare The deadliest form tr.ot death could take, And dare it for the daring's sake.
He stood, the fetters on his hand,—
He raised them haughtily;
It could not wave on high
On many a torture nigh,—
I saw him once before; he rode
Upon a coal-black steed,
And bade their warrior speed.
Of many a soldier's deed;
But now he stood, chained and alone,
The headsman by his side;
The sword, that had defied
Came from that lip of pride;
He bent beneath the headsman's stroke,
"With an uncovered eye:
Who thronged to see him die.
A nation's funeral cry,— Rome's wail above her only son, Her patriot,—and her latest one.—Mies Landon.
RECTITUDE OF CHARACTBU.
The man who is so conscious of the rectitude of his intentions, as to be willing to open his bosom to the inspection of) the world, is in possession of one of the strongest pillars of a, decided character. The course of such a man will be nrrc and steady, because he has nothing to fear from the world, and is sure of the approbation and support of Heaven. While he who is conscious of secret and dark designs, which, if' known, would blast him, is perpetually shrinking and dodging; from public observation, and is afraid of all around, and much more of all above him.
Such a man may, indeed, pursue his iniquitous plans steadily; he may waste himself to a skeleton in the guilty pursuit; but it is impossible that he can pursue them with the same health-inspiring confidence, and exulting alacrity, with him who feels, at every sup, that he is in pursuit of honest ends by honest means.
The clear, unclouded brow, the open countenance, the brilliant eye which can look an honest man steadfastly, yet courteously, in the face, the healthfully beating heart, and the firm, elastic step, belong to him whose bosom is free from guile, and who knows that all his motives and purposes are pure and right. Why should such a man falter in his course? He may be slandered; he may be deserted by the world; but he has that within which will keep him erect, and enable him to move onward in his course, with his eyes fixed on Heaven, which he knows will not desert him.
Let your first step, then, in that discipline which is to giv% you decision of character, be the heroic determination to be honest men, and to preserve this character through every vicissitude of fortune, and in every relation which connect* you with society. I do not use this phrase, " honest men," in the narrow sense, merely, of meeting your pecuniary engagements, and paying your debts; for this the common, pride of gentlemen will constrain you to do.
I use it in its larger sense of discharging all your duties, both public and private, both open and secret, with the most 'crupulous, Heaven-attesting integrity i in that sense, farther. ■which drives from the boeom all Uttle, dark, crooked, sordid, debasing considerations of self, and substitutes in their place * bolder, loftier, and rusbler spirit: one that will dispose you to consider yourseh e« as born, not so much for yourselves, as for your country, and your fellow-creatures, and which will lead you to act, on every occasion, sincerely, justly, generously, magnanimously.
There is a morality on a larger seale, perfectly consistent with a just attention to your own affairs, which it would be the height of folly to neglect; a generous expansion, a proud elevation, and conscious greatness of character, which is the best preparation for a decided course, in every situation into which you can be thrown: and it is to this high and noble tone of character that 1 would have you to aspire.
I would not have you to resemble those weak and meagre streamlets, which lose their direction at every petty impediment that presents itself, and stop, and turn back, and creep around, and search out every little channel through which they may wind their feeble and sickly course. Nor yet would 1 have you to resemble the headlong torrent that carries havoc in its mad career.
But I would have you like the ocean, that noblest emblem of majestic Decision, which in the calmest hour still heaves its resistless might of waters to the shore, filling the heavens, day and night, with the echoes of its sublime Declaration of Independence, and tossing and sporting on its bed, with an imperial consciousness of strength that laughs at opposition. It is this depth, and weight, and power, and purity of character, that 1 would have you to resemble; and I would have you, iike the waters of the ocean, to became the purer by your own action.— William Wirt.
ADDRESS TO THE OCE-iX.
O thou vast Ocean! ever-sounding sea!
Thou symbol of a drear immensity!
Thou thing that windest round tile solid world
Like a huge animal, which, downward hurled
From the b'ack clouds, lies weltering and alone,
T.ashing and writhing till its strength be gone.
Thy voice is like the thunder ; and thy sleep
Is like a giant's slumber, loud and deep.
Thou speakest in the east and in the west
At once; and on thy heavily laden breast
Fleets come and go, and shapes that have no life
Or motion, yet are moved and meet in strife.
The earth hath naught of this; nor chance nor change
Ruffles its surface; and no spirits dare
Give answer to the tempest-waken air;
But o'er its wastes, the weakly tenants range
At will, and wound his bosom as they go.
Ever the same, it hath no ebb, no flow;
But in their stated round the seasons come
And pass like visions to their viewless home,
And come again and vanish: the young Spring
Looks ever bright with leaves and blossoming,
And Winter always winds his sullen horn,
And the wild Autumn with a look forlorn
Dies in his stormy manhood; and the skies
Weep, and flowers sicken when the Summer flies.
Thou only, terrible Ocean, hast a power,
A will, a voice; and in thy wrathful hour,
When thou dost lift thine anger to the clouds,
A fearful and magnificent beauty shrouds
Thy broad green forehead. If thy waves be driven
Backwards and forwards by the shitting wind,
How quickly dost thou thy great strength unbind,
And stretch thine arms, and war at once with heaven!
Thou trackless and immeasurable main! On thee no record ever lived again To meet the hand that writ it; line nor lead Hath ever fathomed thy profoundest deeps, Where happily the huge monster swells and sleeps, King of his watery limit, who, 'tis said, < an move the mighty ocean into storm.— >J:.: wonderful thou art, great element:
And fearful in thy spleeny humours bent,
And hearken to the thoughts thy waters teach,
"Eternity, Eternity, and power."—llxrry CornictSL
The Bible is the only book which God has ever sent, the only one he will ever send, into this world. All other books are frail and transient as time, since they are only the registers of time; but the Bible is durable as eternity, for its pages contain the records of eternity. All other books are weak and imperfect, like their author, man; but the Bible is a transcript of infinite power and perfection. Every other volume is limited in its usefulness and influence; but the Bible came forth conquering and to conquer: rejoicing as a giant to run his course, and like the sun, ■' there is nothing hid from the heat thereof." The Bible only, of all the myriads of books the world has seen, is equally important and interesting to all mankind. Its tidings, whether of peace or of woe, are the same to the poor, the ignorant, and the weak, as to the rich, the wise, and the powerful.
Among the most remarkable of its attributes is justice; for it looks with impartial eyes on kings and on slaves, on the hero and the soldier, on philosophers and peasants, on the eloquent and the dumb. From all, it exacts the same obedience to its commandments, and promises to the good, the fruits of his labours; to the evil, the reward of his hands. Nor are the purity and holiness, the wisdom, benevolence and truth of the Scriptures less conspicuous than their justice. In sublimity and beauty, in the descriptive and pathetic, in dignity and simplicity of narrative, in power and comprehensiveness, depth and variety of thought, in purity and elevation of sentiment, the most enthusiastic admirers of the heathen classics have conceded thuir inferiority to the Scriptures.
The Bible, indeed, is the only universal classic, the classic of all mankind, of every age and country, of time and eternity, more humble and simple than the primer of a child, more grand and magnificent than the epic and the oration, the ode and the drama, when genius with his chariot of fire, and his horses of fire, ascends in whirlwind into the heaven of his own invention. It is the best classic the world has ever seen, the noblest that has ever honoured and dignified the language of mortals.
If you boast that the Aristotles, and the Platos, and tho Tullies, of the classic age ;* dipped their pens in intellect," the sacred authors dipped theirs in inspiration. If those were the "secretaries of nature," these were the secretaries of the very Author of nature. If Greece and Rome have gathered into their cabinet of curiosities the pearls of heathen poetry and eloquence, the diamonds of Pagan history and philosophy, God himself has treasured up in the Scriptures, the poetry and eloquenco, the philosophy and history of sacred lawgivers, of prophets and apostles, of saints, evangelists, and martyrs. In vain may you seek for the pure and simple light of universal truth in the Augustan ages of antiquity. In the Bible only is the poet's wish fulfilled,—
"And like the sun be all one boundless eye."
THE DOWNFALL OP POLAND.
O sacred Truth! thy triumph ceased a while,
Warsaw's last champion from her height surveyed,
He said, and on the rampart-heights arrayed
In Tain, alas! in -vain, ye gallant few!
The sun went down, nor ceased the carnage there;
O righteous Heaven! ere Freedom found a grave,
Departed spirits of the mighty dead!
Yes, thy proud lords, unpitied land! shall see
THE LOVE OF TRUTH.
Truth is the one legitimate object of all intellectual endeavour. To discover and apprehend truth, to clear up and adorn it, to establish, and present, and commend it,—these are the processes and the ends of study and literature. To discern the things that really are, and how they are, to distinguish reality
from appearance and sham, to know and declare the truth in outward nature, in past time, in the results of speculation, in consciousness and sentiment,—this is the business of educated mind. Logic and the mathematics are instruments for this purpose, and so is the imagination just as Btrictly. A poem, a play, a novel, though a work of fiction, must be true, or it is a failure. Its machinery may be unknown to the actual world; the scene may be laid in Elysian fields, or infernal shades, or fairy land; but the law of truth must preside over the work; it must be the vehicle of truth, or it is nought, and is disallowed. The Tempest, the Odyssey, and Paradise Lost, derive their value from their truth ; and I say this, not upon utilitarian principles, but according to the verdict which every true soul passes upon them, consciously or unconsciously. Lofty, holy truth, made beautiful and dear and winning to the responsive heart,—this is their charm, their wealth, their immortality. There is no permanent intellectual success but in truth attained and brought home to the eye, the understanding, or the heart.
And for the best success in the pursuit of any object there must be a love of the object itself. The student, the thinker, the author, who is true to his vocation, loves the truth which he would develope and embody. Not for bread, not for fame, primarily, he works. These things may come, and are welcome; but truth is higher and dearer than these. Great things have been done for bread and fame, but not the greatest. Plato, pacing the silent groves of the academy, and Newton, sitting half a day on his bedside, undressed, and his fast unbroken, rapt in a problem of fluxions; Dante solacing the bitterness of exile with the meditations that live in the Commedia, and Bacon taking his death chill in an experiment to test the preserving qualities of snow; Cuvier, a lordlier Adam than he of Eden, naming the whole animal world in his museum, and reading the very thoughts of God after him in their wondrous mechanism; Franklin and Davy wresting the secrets of nature from their inmost hiding-place; Linnceus studying the flora of the arctic circle in loco; and that fresh old man who startles the clefts of the Rocky Mountains with his rifle, to catch precisely the lustrous tints of beauty in the plumage of a bird;— these men, and such as they, love truth, and are consecrate, hand and heart, to her service. The truth as she stands in God's doings, or in man's doings, or in those thoughts and affections that have neither form nor speech, but which answer from the deep places of the soul,—truth, as seen in her sublimities or her beauties, in her world-poising might or her
Iseeming trivialities,—truth, as she walks the earth embodied in visible facts, or moves among the spheres in the mysterious laws that combine a universe and spell it to harmony, or as she sings in the upper heavens the inarticulate wisdom which only a profound religion in the soul can interpret,—truth, in whichsoever of her myriad manifestations she, has laid hold of noble affinities, and brought their being into holy captivity;— such men have loved her greatly and fondly; the soul of genius is alwayB pledged to her single-hearted and sweet affiance, or else it is genius baffled, blasted, and discrowned.—George Putnam.
Now ready, Vol; I., in cloth boards, 53. Cd;
THE POPULAR BIBLICAL EDUCATOR.
This work is intended to supply the people with such information relating to the stndy of the Bible as the Popular Educator has given in referenco to Secular instruction. It contains a Literary Iilatory of the Sacred Books —Accounts of their Original Teat—Canonical Authority, and most Ancient Versions—The Principle and Laws of Interpretations, and the Methods of Discovering the Literal or Symbolical Meaning of Inspired Writings— Illustrations of the Geography and Natural History of Palestine—The Manners and Customs, the Laws and Worship of its People—The Antiquities of the Pour Great Monarchies—The Fulfilment of Prophecy concerning them and other anciont nations—and the Fruits of modern Travel and Diseorery in the East, etc. The work Is written in a popular style, and is therefore specially adapted to supply Families, 8unda>school Teachers, and others, with that amount of information respecting the Holy Bible which they need in order to meet the charges of Infidels and the subtleties of Romanists, and to confirm and establish their own minds in the genuineness and authenticity of Holy Writ. Wherever the subject requires Pictorial Illustrations tnejr are introduced.
ON PHYSICS, OR NATURAL PHILOSOPHY.
[Ctntinued from page 795.)
Aurora Borealis—The name aurora borealis, or rather aurora polaris, is applied to an extremely remarkable phenomenon -which often appears in the atmosphere at the two poles. When it appears at the north pole, it is called aurora borealis, or, in popular language, the northern lights, and when it appears at the south pole, it bears the name of aurora australti. The aurora borealis appears more frequently than the lumra australis, but the reason is, probably, because there are mire persons to observe in the northern than in the southern regions. We extract from the Treatise on Meteorology, by Messrs. Becquerel, the following description of an aurora borealis, as observed at Bossekop, in Norwegian Lapland, at 70 degrees north latitude, in the winter of 1838-9.
In the evening, between four and eight o'clock, the fog, which usually prevails north of Bossekop, becomes coloured in the upper part. This light gradually gets more regular, and forms a sort of arch of a pale yellow colour, with its concave side towards the earth and its highest point apparently in the magnetic meridian.
Before long, blackish stripes in regular order separate the
j the whole becomes gradually indistinct, or suddenly vanishes. ! Scientific ob-ervers have noted 150 appearances of the i aurora borealis in the course of 200 days in the northern 'regions; but it appears that at the poles the nights without any aurora are altogether exceptions, so that we may infer their existence every night, though occasionally too faint to be clearly distinguished. Sometimes the same aurora has been seen at the same time at Moscow, Rome, and Cadiz.
Many hypotheses hpve been started as to the cause of this phenomenon. The invariable direction of their arches in rela tion to the magnetic meridian, and the perturbations which they produce in the mariner's compass, snow that they must be attributed to electric- currents which proceed from the poles towards the tipper regions of the atmosphere; but the .•rigin of this electricity i» entirely unknown.
CLIMATOLOGY. Mean Temperature.—The mean temperttwe, or simply the temperature, of a day, is that which is obtained by taking the ■um of 24 observations made with the thermometer from hour to hour, and dividing this sum by 24. Experience shows that the mean temperature may be very nearly obt lined by taking the mean between the maximum and minimum temperatures of the day and the night, which may be determined by means of the maxima and minima thermometer. The thermometer should be sheltered from the sun's rays, raised above the ground, and removed from every substance which might influence it by the radiation of heat.
luminous jarts of the arch. Luminous rays are formed, which lengthen or become shorter, slower or instantaneously, their brightness increasing and diminishing suddenly. The lower ends of these rays always exhibit the brightest light, and form an arch of more or less regularity. The length of the rays is ■very varied, but all converge towards one point in the sky, which is indicated by the prolongation of the southern extremity of the inclination needle. Sometimes the rays are prolonged till they meet, and thus torm the fragment of a luminous cupola.
The arch continues to ascend towards the zenith, exhibiting an undulating motion in its light. Sometimes one of its feet, and even both, are separated from the horizon. The folds are then more distinct and more numerous. The arch is nothing more than a long band or strip of rays, which are twisted ana separated in several parts, forming graceful curves, which -wind about and present the appearance known by the name of the corona borealis, or northern wreath, fig. 489. The brightness of the rays, varying suddenly in intensity, reaches that of stars of the first magnitude, the rays dart with rapidity, and the curves form and unfold like the coils of a serpent. Then the rays become coloured; the lower part is red, the middle green, and the remainder retains its clear yellow tint. At last the bsightness diminishes, the colours disappear, and
The temperature of a month is the mean of that of thirty days, and the temperature of a year is the mean of that of twelve months. Lastly, the temperature of a place is the mean of its annual temperature fur a great number of years. In all cases the temperature is that of the air, not that of the earth.
Causes which modify the Tempentittrt of the Air.—The causes which affect the temperature of the air are principally, the latitude, the altitude, the direction of the wind, and the nearness of the sea.
1. Influence of Latitude.—The influence of the latitude results more or less from the obliquity of the solar rays; for the quantity of heat absorbed being greater in proportion as the rays approach more nearly to perpendicularity, the consequence is, that the heat absorbed from the sun decreases from the equator to the poles, since the rays are more and more oblique to the horizon. But this loss is partly compensated in summer, in the temperate and frigid zones, by the length of the days. At the equator, where the length of the day is invariable, the temperature is nearly invariable also; in our latitude, and in countries still further north, where the days are very unequal, the temperature varies very much, but in the summer it sometimes rises almost as high as at the equator.
Further, the lowering of the temperature, which result*