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the names of the only makers that have descended to No. II.
posterity as men who accomplished what none else ON THE CONSTRUCTION OF THE Violin.
had done or could do,—the only element perhaps in
human fame. Many a violin of these makers bas The reader is of course aware of the construction been spoiled in the vain attempt to discover the of the 'modern Violin. A curious and somewhat secret of its workmanship; expert artists have taken fantastically shaped box, with a handle springing them to pieces, have constructed numberless instrufrom one end, is the first object that strikes our
ments with the most scrupulous attention to their attention. Four strings are tightly stretched by model, and the failure has been, in all cases, entire. attachments at each end, which strings rest upon a New constructions have been attempted, and scienbridge placed near their upper terminations. The tific models founded on the known principles of strings are vibrated by means of a bow, which vibra- sound, and yet the superiority of the Cremonese tions are communicated along the bridge to the upper artists still remains unquestioned. table of the instrument,—then to the mass of air
But the most valuable contribution to our knowwithin the box, and again to the lower table by means ledge of the construction of the Violin, is the expeof a sounding post, the ends of which touch both rimental instrument of M. Savart. A full descriptables. This post is called by the French, l'ame du tion of this instrument is to be found in the Manual Violon, or, the soul of the Violin. The vibrations of of Natural Philosophy, by Mr. Tomlinson, who, we the enclosed air are further assisted by a bar of believe, was the first to lay all the details of M. wood enclosed within the box, and passing in the Savart's Violin before English readers. We owe the direction of its length, called the bar of harmony. following account to Mr. Tomlinson's description, as Two apertures are made in the upper table of the also to the report of the Royal Academy of Sciences instrument, of the form of an italian S, whereby the of Paris, on the merits of the new instrument. vibrations are more freely communicated to the en
M, Savart began his inquiry by endeavouring to closed air. The bridge is curved, in order to allow distinguish the essential parts of the Violin from its the bow to touch either of the middle strings sepa- empirical or ornamental details. He soon concluded rately, and a hollow on each side of the case, exter- that the vaulted form of the face and back is not a nally, allows a freer motion to the bow while playing necessary part of its structure; he therefore conupon the two other strings.
structed his Violin with flat surfaces, each formed of The strings are attached at the lower end to pegs two pieces, 2 lines thick at one edge, and gradually in the handle of the instrument, by turning of which tapering towards the other edge, which was 1 line the strings are stretched more or less tightly, and thick: the thicker edges of each pair of tablets were thus the instrument is tuned.
then joined together. He next determined that the A really good Violin on this construction is a
sides of the Violin ought not to be fancifully curved, costly instrument. A good-toned Violin cannot be but straight, in order that they might enter into unbought in England or France for less than fifty disturbed vibration from corner to corner of the inguineas, and many have been sold for 250 guineas. strument, and thus contribute to augment the sound. An instrument made by Stradivarius can always be All the wood thus employed was cut and arranged in sold for 100 guineas. The choice, too, of a Violin is the direction of the fibres, or longitudinally, as it is difficult : none but a master can determine its real called. The form of the instrument was that of a value. It is said that new instruments are never trapezoid, or four-sided figure, of which the lower good; for if they have a tolerable tone at first, it will breadth was less than that of the upper. In common soon deteriorate. The best Violins become so by Violins, the bar of harmony and the sounding-post beginning with poor and insufficient tones, and gra
are placed one on one side, and the other on the dually improving. The Violin is a slow pupil, for it other side of the central line or axis of the instrudoes not « discourse eloquent music” under fifty ment: Savart placed the bar of harmony along the years' hard practice; but it then becomes invaluable. central line, and thus equalized the vibratory action
The most memorable Violin-makers are the Amatis of both sides. of Cremona; Andreas, Jerome and Anthony Amati,
The sounding-post has usually been considered as and Nicolas, the son of Anthony : the latter flou
a kind of support to the upper surface, but Savart rished about the year 1600. This family certainly found that its important office is to communicate the constructed the finest violins in the world, and it is vibrations from the face to the back of the instrusupposed that the elder Amati discovered some secret ment, and the point at which he fixed the post in his connected with their successful construction, trans- Violin was such as to convey the sonorous vibrations mitted it to his sons, and that it died with Nicolas,
more perfectly and energetically from the face to the the younger branch of the family. Their Violins are
back of the instrument. distinguished by elegance of shape, sweetness and
The incisions made on the face of the instrument roundness of tone.
were next attended to. Savart covered these two Stradivarius, the elder and the younger, were also openings with paper, and found the sound to be maof Cremona. The latter was flourishing in 1700. terially injured, because the enclosed air had no direct He inscribed on his Violins the following signature,- communication with the external air. He made the ANTONIUS STRADIVARIUS CREMONENSIS FACIEBAT, openings in the form of a parallelogram, that is, the ANNO
edges to be straight and parallel, so that the fibres It is remarkable, also, that Cremona produced the and the long margins of the holes were in the same celebrated Guarnerius. His inscription is,
direction, and the vibrations of the wood at those ANDREAS GUARNERIUS, FECIT CREMONÆ, SUBSTINTO, parts were rendered more symmetrical, while at the SANCTÆ TERESE, 1680.
same time fewer fibres were cut than is the case with Stainer, a native of Tyrol, constructed Violins the form of the apertures usually adopted. remarkable for their full and piercing tone, such as Before Savart mounted the various parts of his has never been equalled. His inscription is,-- Violin, he took care that each part should perform its JACOBUS STAINER, IN ABSOM PROPE EniPONTUM, 1647. vibrations in a system similar to that of all the rest.
Albani, also a native of Tyrol, is another celebrated He imagines that the celebrated makers before named, maker: and here we close the list, for the above are were aware of the importance of this principle.
The Violin of Savart was soon put to a severe test.
THE ADVICE OF A PHILOSOPHER. A committee was appointed to examine and report on Take especial care that thou delight not in wine, for there its merits. In this committee we find the distin
never was any man that came to honour or preferment that guished names of Biot, Prony, Haüy, Charles, toge- loved it; for it transformeth a man into a beast
, decayeth ther with Cherubini the composer. The report of health, poisoneth the breath, destroyeth natural heat
, brings a man's stomach to an artificial heat, deformeth the face
, this committee is highly favourable. The new Violin was played by Lefebvre, the celebrated Parisian rotteth the teeth, and to conclude, maketh a man con: violinist, alternately with a Stradivarius; and the men; hated in thy servants, in thyself and companions ;
temptible, soon old, and despised of all wise and worthy committee could not detect any difference between
for it is a bewitching and infectious vice. A drunkard will the tones of the old and the new instruments, when never shake off the delight of beastliness; for the longer they were played alternately in an adjoining apart- it possesses a man, the more he will delight in it, and the ment, except by a little more sweetness in the tones
older he groweth, the more he will be subject to it; for it of the new one.
dulleth the spirits and destroyeth the body, as ivy doth the
old tree; or as the worm that engendereth in the kernel of On this subject Mr. Tomlinson offers a remark in
the nut. which we cordially join:
Take heed, therefore, that such a cureless canker pass This was probably the first attempt to reduce fiddle- not thy youth, nor such a beastly infection thy old age; for making to scientific principles; and the success which then shall all thy life be but as the life of a beast, and after attended it ought to encourage similar efforts. Savart thy death, thou shalt only leave a shameful infamy to thy made many violins such as we have described, which had posterity, who shall study to forget that such a one was no pretensions to elegance or high finish, but all possessing their father. Anacharsis saith, the first draught serreth the desirable qualities which we are in the habit of attri- for health, the second for pleasure, the third for shame, the buting to the good old” Violins. Should any of our
fourth for madness; but in youth there is not so much as readers be of a mechanical turn, they might construct good one draught permitted; for it putteth fire to fire; and Violins at the cost of a few shillings, by attention to the therefore except thou desire to hasten thine end, take this main points of difference between the common instruments for a general rule, that thou never add any artificial heat to and those above described, -all of which were made by thy body, by wine or spice, until thou find that time hath Savart's own hands.
decayed thy natural heat, and the sooner thou beginnest to The best harps and pianos are made in England: help nature, the sooner she will forsake thee
, and trust
Who have misfortunes, saith Solomon, the best violins can now be said to be made nowhere. altogether to art.
who have sorrow and grief, who have trouble without figlitSavart's Violin was made several years ago ; but it ing, stripes without cause, and faintness of eyes ? even they has never become popular, or even known in France, that sit at wine, and strain themselves to empty cups. where we should suppose it would soon flourish like Pliny saith, wine maketh the hand quivering, the eyes a plant in its native soil : but in England the instru-watery, the night unquiet, a stinking breath in the mornment has yet to be introduced, and we venture to ing, and an utter forgetfulness of all things. hope that Mr. Tomlinson's description, and the present he cannot keep a secret. Wine maketh man not only a
Whoso loveth wine, shall not be trusted of any man, for article, will tend to bring about so desirable an effect. beast, but a madman; and if thou love it, thy own wife, thy
children, and thy friends will despise thee. In drink, men care not what they say, what offence they give, forget
comeliness, commit disorders; and to conclude, offend ail 'Neath summer's bright and glorious sky,
virtuous and honest company, and God most of all, to whom While proudly waves the golden grain,
we daily pray for health, and a life free from pain ; and yet And through the falling fields of rye,
by drunkenness and gluttony, (which is the drunkenness Comes on the joyous reaper train
of feeding) we draw on, saith Hesiod, a swift, hasty, unWhile nature smiles, and hill and plain
timely, cruel, and an infamous old age. And St. Augustine Are tranquil as the sleeping sea,
describeth drunkenness in this manner :-"Drunkenness And peace and plenty brightly reign
is a flattering devil, a sweet poison, a pleasant sin, which By homestead, hearth, and forest tree.
whosoever hath, hath not himself, which whosoever doth God of the seasons, unto thee we raise
commit, doth not commit sin, but he himself is wholly sin." Our hands and hearts in melody and praise.
Innocentius saith,-“What is filthier than a drunken There is a sweet breath from the hills,
man, to whom there is stink in the mouth, trembling in the The incense from the mountain air,
body; which uttereth foolish things, and revealeth secret Which from a thousand flowers distils
things; whose mind is alienate and face transformed ? Its odours delicate and rare
There is no secresy where drunkenness rules; nay, what We feel its balm-we see it there
other mischief doth' it not design? whom have not plentiful Among the bending wheat-blades move,
cups made eloquent and talking ?" Kissing their tops in dalliance fair,
When Diogenes saw a house to be sold, whereof the As if its very life were love.
owner was given to drink, “ I thought at the last," quoth God of the harvest, whence its breezes blow,
Diogenes, " he would voinit a whole house," — SIR WALTER Receive the humble thanks thy creatures owe.
I CANNOT call riches better than the baggage of virtue ; Of this old oak, our verdant dome,
the Roman word is better, "impedimenta ;" for as the bag. And watch the evening shadows fadem
gage is to an army, so is riches to virtue; it cannot be O'er mount and meadow, lawn and glade,
spared nor left behind, but it hindereth the march; jea, They spread their deep'ning tints of gray,
and the care of it sometimes loseth or disturbeth the vie Till all the scene their hues pervade,
tory; of great riches there is no real use, except it be in And twilight glories melt away.
the distribution: the rest is but conceit.-Bacon. God of the world, who round thy curtain throws, Thanks for the time of quiet and repose.
It is an old saying, that charity begins at home; but this How still is nature all around !
is no reason it should not go abroad : a man should live No song is sung, no voice is heard
with the world as a citizen of the world; he may have a Save here and there a murmuring sound,
preference for the particular quarter or square, or even alley As if some restless sleeper stirred ;
in which he lives, but he should have a generous feeling for The grasshopper, night's clam'rous bird,
HYMN IN HARVEST TIME.
the welfare of the whole.-CUMBERLAND.
JOHN WILLIAM PARKER, WEST STRAND. We bless Thee for the gifts we ne'er can pay.
PUBLISHED IN WEEKLY NUMBERS PRICE ONE PENNY, AND IN MONTHLY PARTS, Thos PSON.
Sold by all Booksellers and Newsvenders in the kingdom.
Wished Spring returns; and from the hazy south,
present fit localities for the habitations of man, would The welcome Sun, just verging up at first,
become ice-bound, and consequently uninhabitable. By small degrees extends the swelling curve !
But do our wants cease here? should we be content with Till seen at last for gay rejoicing months,
constant Summer? No; the grass would become withered, Still round and round, his spiral course he winds,
the flocks would lose the food with which they were for a And as he nearly dips his flaming orb,
while nourished, the brooks and rivulets would be dried Wheels up again, and re-ascends the sky.
up, pestilential diseases would ensue from the putrefaction THE SEASONS.
of animal and vegetable bodies, and man himself, enervated
and debilitated by excess of heat, would droop as if the THERE are but few phenomena presented to the notice of vivid spark of life were sinking out. These results are man more beautiful and, at the same time, more instructive prevented by the wise ordinations of Providence, by which to him, than the regular succession of Seasons, and the Summer is succeeded by Autumn; a season which at the varied benefits which they confer. The cold and bleak same time softens the descent from Summer to Winter, temperature of our Winter is rendered less rigorous by the and brings to perfection those fruits which are to serve for artificial processes by which we obtain warmth within our the good of man, and other animals, during the remaining dwellings; but still the genial and refreshing air of Spring portions of the year. is looked forward to by all as a delightful change from the Thus, then, does each season bring with it its joys and dreariness of Winter. The pleasing associations connected advantages; and thus are we taught to admire the exquiwith Spring, when both animal and vegetable life seem to site mechanism and adjustment of the heavenly bodies, by acquire new vigour, and a new lease, as it were, of exist which these joys and advantages are imparted to us. But ence, would not alone suffice for the wants, either natural how are these seasons brought about ? and why is it that or artificial, of man. The Summer's Sun is required to ripen the Sun sheds such a varying amount of cheering influence and bring to perfection the fruits of the Earih, whether to on the Earth at different seasons ? The answer to this be used directly by himself as articles of food, or to nourish question is admirably calculated to show, what wonderful those animals which subsequently furnish him with diet. effects spring from apparently small causes. The reason The Summer's Sun is also necessary to melt the ice, which for the succession of the various seasons is to be found in makes the polar regions one sterile and dreary waste, unfit the simple circumstance, that the Earth does not revolve on alike for almost every species of animal or vegetable. her axis in the same plane in which she revolves round the Were it not that the genial warmth of the Summer's Sun Sun; if those two planes coincided, we should have no dissolves large portions of ice, the frozen regions would variety of seasons; the same intensity of heat or of cold gradually extend their boundary towards the equator; and would be experienced at the same place, at every season of those countries which are now called temperate, and which the year. This important circumstance we now proceed to Vol. XIII.
explain, and to illustrate by reference to the diagram which Summer and Winter : the large amount of heat received forms the frontispiece of the present paper.
by the northern hemisphere, in comparison with that reBefore we enter upon that inquiry, however, it will be ceived by the southern, produces the season of Summer to desirable to describe certain circles, which are supposed to the former, and Winter to the latter. If at this season we be drawn on the surface of the Earth, and in doing so we mark the boundary line between the enlightened and the must refer to the figure of the globe at the end of this dark hemispheres of the Earth, it will be seen that this article.
line will just graze the polar circles: it will likewise be The Earth is, as before stated, nearly a perfect globe, of seen that, if we draw a line through the centres of the Sun which the equatorial diameter is a little greater than the and Earth, that line will pass through the tropic of Cancer. polar; and it has, likewise, been observed, that this globe, We next find the Earth in that position which she attains besides its revolution round the Sun in the course of a year, about the 21st of September, when the northern Autumn revolves on its own axis, from west to east, once in every is felt. We observe that the Earth's position is such as it twenty-four hours. The two ends of this axis are the north was in the Spring, when the two poles were exactly equi. and south poles, P and Q. The circle which surrounds distant from the Sun. Here, then, we have the season of the Earth, exactly midway between the two poles, is Autumn, in which the direct light and heat of the Sun are called the equator, E R. Another line crossing the equator equal to what they are in Spring. This is not what we are in an oblique direction but not given in the figure, is in the habit of supposing, because the sensation of warmth called the ecliptic, from the circumstance that when- | is decidedly greater in Autumn than in Spring; but the ever an eclipse occurs, either solar or lunar, the Sun, apparent contradiction is thus accounted for: although the the Moon, and the Earth are all quite, or very nearly, direct heat of the Sun is the same in Autumn as in Spring, in this plane. The ecliptic is a circle which, like the on account of the distance of the Earth from the Sun being equator, goes round the Earth, and represents the appa. equal at those two periods, and the Sun's rays being rerent path of the Sun in the course of a year; that is, if ceived at the same degree of obliquity at any given spot,a body were held exactly in a right line between the yet the Autumn heat is increased by the accumulated heat centre of the Sun and the centre of the Earth, the shadow of the Summer. The surface of the Earth receives in of that body would travel along the ecliptic. These two Summer so large a portion of heat, that a considerable circles, the equator and the ecliptic, are called greater time elapses before it can be radiated upwards into the air, cireles, because their planes pass through the centre of the and thus is formed a magazine of heat, by which the auEarth, and divide the Earth into two equal parts; whereas, tumnal warmth of the Sun's direct rays is augmented; and all other circles are denominated less circles, because their hence we are furnished with the fructifying temperature so planes divide the Earth into two unequal parts. There are propitious for the time of harvest. also two circles which surround the Earth, parallel to the From the 21st of September, the Earth progresses towards equator, and at a distance from it equal to about 231. the north-wintry position, which she attains about the 24th These are called tropics, from a Greek word which implies of December. Here we find a marked change in ihe turning, as the Sun, when it has arrived at those parts, relative position of the north and south poles: the north begins then to turn away again northward or southward, as pole is turned away from the Sun, while the south pale the case may be ; the circle which is nearer to the north inclines towards him. Hence the north pole and all the pole being the tropie of Cancer, and that which is nearer adjacent parts, including, in fact, the whole northern to the south pole being the tropic of Capricorn. The posi- hemisphere, receive a much smaller share of the Sun's heat tion of these two circles is determined by the greatest than is enjoyed by the southern hemisphere; and thence distance which the ecliptic recedes from the equator; and come the northern Winter and the southern Summer. The they receive their name from the circumstance of the Sun inhabitants of the northern hemisphere strive to compensate being at the time in the constellation which gives the name to for the deficiency of the Sun's heat by additional cloiling the tropic. There are also two small circles which surround and additional contrivances for procuring artificial warnth the poles, at a distance from the poles exactly equal to the in their dwellings, while the inhabitants of the south luxudistance of the tropics from the equator. The arctic circle riate in the overarching light and heat of the Sun. Our is that which surrounds the north pole, at a distance of emigrant countrymen in New South Wales and Van 23°; the antarctic circle is that which surrounds the south Diemen's Land experience the joys of Summer at the pole. The term antarctic signifies opposite to the arctic, time when we are striving to exclude from our hearths the which latter term is derived from the Greek for a bear: the chilling blasts of Winter. If a vessel be six months perlittle bear is a constellation over the north pole of the Earth. forming the voyage from England to Australia, and leave
We now turn more particularly to the subject of our England in the middle of Summer, it reaches Australia also frontispiece, where we observe an oral line, which the in the middle of Summer; that is, it would have a northern Earth describes annually about the Sun, or which the Sun Summer at the commencement of the voyage in June, and appears to describe round the Earth. The Earth moves a southern Summer at the termination of the voyage in round this orbit in a year, and we have the position of the December: the vessel follows the declination of the Sun in Earth in that orbit at four different periods of the year, the seasons; that is, its diminishing and increasing distance about three months asunder. It will be seen that the axis from the equator. When the vessel set sail, the Sun was of the Earth is inclined towards one side, and that it vertical considerably to the north of the equator: as the remains parallel throughout the whole of the Earth's revo- vessel crossed the line, the Sun was vertical thereabouts at lution; that is, that there is exactly the same obliquity, 'or the same time: and when the vessel arrives at its destinasloping direction, at all seasons of the year; this causes tion, the Sun has arrived at its greatest southern distance the equator to form with the ecliptic an angle of about 23. from the equator,
Let us now suppose the time of the year to be the 21st Such is the effect which the obliquity of the Earth's of March, and let us trace the progress of the Earth in axis produces on the succession of seasons: if that axis her annual orbit. She is then in the position which affords were perpendicular to the plane of the Earth's orbit, or, the northern Spring, and the Sun is at exactly the same which amounts to the same thing,-if there were always distance from both poles; that is, if the centres of the Sun some part of the equator precisely between the centres of and the Earth were connected by a right line, this line the Sun and the Earth, we should have no vicissitudes of would pass through the equator, and would therefore be seasons, because the Sun would be always at an equal equidistant from the two poles. Now it is not difficult to distance from both poles. see that in this case the Sun imparts just as much heat to We have stated * that the Sun is nearer to the Earth in one pole as to the other, affecting either hemisphere alike. the Winter than in the Summer; and it would seem that At about the 23rd of June the Earth is at the position the Earth should receive a larger portion of heat in De. denoted by northern Summer. Here we notice that the cember than in June; but the obliquity of the Earth's asis, Earth is farther from the Sun than it was three months which gives rise to the phenomena of seasons, almost altobefore: but the excess of heat at this latter period is due gether obviates the mere effect of propinquity. The conto a circumstance altogether separate from the actual dis- sequence of this obliquity is that, in the middle of Summer, tance of the Sun. The obliquity of the axis of the Earth the Sun attains an altitude, or elevation, above the horizoni, is the important circumstance to which we have to keep our of sixty-two degrees; while in the middle of Winter, be attention. We perceive that, in the northern Summer, the does not reach higher than fifteen degrees, in the latitude north pole is nearer to the Sun than the south pole: hence of London. This difference of meridian-altitude is due to a greater amount of heat is received from the Sun by the the greater or less distance of the spot, where the sun 15 northern part of the Earth than by the southern, at this vertical, from the parallel of latitude in which London is period, This is the sole origin of the results of the seasons,
• See Saturday Magasine, Vol. XIII., p. 35.
situated : and, as the sun passes round our globe every By this plan astronomers can describe to one another and twenty-four hours, it is constantly describing a winding to their readers, the position of any of the moving learenly course from one tropic to the other. It is this spiral or bodies. In the early ages, when the Chaldean shepherds winding motion, which the poet Thomson alludes to in watched the heavenly bodies through the clear and serene our quotation at the beginning of this paper. Now the atmosphere of Syria and Mesopotamia, and at a later period simple circumstance of the Summer altitude of the Sun when the Arabians cultivated astronomy, the stars were increases the amount of heat received, in two different ways; parcelled out according to some fancied resemblances to first, the direct rays of the Sun have more power at a high, animals and other objects, as may be seen on a celestial than at a low elevation, because they have a less thickness globe. In many instances it baffles both the eye and the of atmosphere to pass through; second, a longer time must imagination of a modern observer, to detect any resemblance be employed by the Sun in attaining a great altitude above to the objects named in this celestial menagerie; but in so the horizon, than in attaining a smaller altitude; so that far as it enables us to map out the stars into convenient he must then be above the horizon a greater number of and small portions, the arrangement is of service. Each hours during the day, and consequently shed a larger of these sets of stars is called a constellation, or assemblage amount of light and heat in the case of the greater altitude of stars. It is to this plan of comparing the clusters of than of the smaller. These are occurrences with which we stars to the forms of certain animals and other objects, and are familiar from year to year, because they exert too ex- the practice of representing them on our globe, that Darwin tensive an influence on the affairs of life to escape our alludes in the following lines :notice. If, however, we compare these occurrences with the different positions of the Earth, as represented in the
So erst, ere rose the science to record
In lettered syllables the volant word; frontispiece, we shall see that the whole depends upon
Whence chemic arts, disclosed in pictured lines, whether the northern hemisphere, in which we live, is
Lived to mankind by hieroglyphic signs ; turned nearer to, or farther from, the Sun, than the southern
And clustering stars, portrayed on mimic spheres, hemisphere.
Assumed the forms of lions, bulls, and bears.
In the course of the circuit which the Sun appears to Fig. 22.
make among the stars in a year, the ancients managed to
are the following: -
.the Twins Cancer
.the Crab....... Leo
...the Lion....... R
Now, when the Sun is said to be in Aries, for instance, SUMMER AND WINTER ALTITUDES OF THE SUN IN THE LATITUDE it means that he is situated between the Earth and that
cluster of stars, which is named after the Ram; and so
accordingly with any other cluster of stars. When these But we cannot help noticing that, as the southern hemi- names were first given to the different sets of stars, the sphere has its Summer while we have our Winter, although Sun, on the 21st of March, was about coming between the we may not feel our Winter to be much mitigated by greater Earth and the sign Aries, or Ram, and that position was propinquity to the Sun at that season, it would follow that called the first point of Aries; for a long series of years, the southern Summer should be warmer and the Winter therefore, the Sun arrived at the first point of Aries on the colder than with us; and the testimony, if we may rely 21st of March. In order now to obtain precision in naming upon it, of those who have tried the experiment in both the position of the Sun at any other period, the whole regions of the world, corroborates the inference which apparent circle described by him was divided into twelve science had previously drawn.
equal parts; whether or not these parts exactly coincided Now, in order to estimate the real position of the Earth with the outlines of the clusters of stars from which they in space at any given time, or the apparent position of the were named. Each of these portions, or signs, was further Sun, the astronomers of old time devised a method, which divided into thirty equal parts, called degrees, so that the is still in use, and which we now proceed to detail.
position of the Sun at any period could be expressed with The myriads of stars with which the heavens are studded, great accuracy. This apparent motion of the Sun is from and whose glittering brilliancy forms such a sublime object west to east, -or from the sign Aries to Pisces,—and results of contemplation in our long Winter nights, we call for the from the motion of the Earth in the same direction. most part fixed; as we find them maintain consiant dis- In the course of ages, however, it was found that the tances and positions with regard to one another: this cir- Sun did not occupy the same position in the constellation cumstance gives them a value as standards, by which we Aries on the 21st of March, as he had occupied at an may compare the motions of other bodies. If we use a earlier period. This is occasioned, not by a motion of the twelve-inch rule to measure the distance between two points, stars, but by a change in the point of the Earth's orbit at the value of the rule depends upon the circumstance that which the two hemispheres are equally exposed to the Sun: the inches are always exactly the same distance apart; and a point, which is generally expressed as that in which the so it would be with any other standard of measurement. plane of the equator cuts the plane of the ecliptic. This When we consider that the Sun, immensely distant as he point is called the equinox, from the circumstance that the is, is yet infinitely nearer than the fixed stars, whose distance day and night are equal to all parts of the world, when the has never yet been ascertained, we shall perceive that he sun is at the point of intersection. This motion of the must very frequently appear to come between the Earth equinox is called the precession of the equinoxes; or more and some one star, so as to conceal the star and the Earth properly the recession, because they appear to travel backfrom each other.
It has, therefore, beeu found convenient wards, and the signs forwards : it is occasioned by the to refer the position of the Sun to that star, the position of attraction of the Sun and Moon for the mass of terrestrial the latter being previously known.
matter at the equator. This precession is, however, so