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with which sun-light seems also to have accordances in their flight to the earth.

This fact indicates, if it were not a palpable fact without it, that all the relations, including light, which can subsist between systems or any orbs are columnar and pot directed to any place where is no reciprocant whatever.

Does not the centripital tendency of gravity, in the earth's vicinity, aid in swerving the transmiting media of light out of the line before deseribed ? I think it does aid in forming wild rays and aberations as they called.

If this suppositton be true then the earth may be, as it were, but a seather in respect to gravitating connection with stars and as a sequence the luminous effluence from a klar directed upon our globe, may stand as a star-image upon a cone of relations, stopping far from us, and thus we see oply this image which serves to direct lellescopic vision to the real column and the star at its base.

But if the star be in motion such a vibratory motion would be attained by the column that the annual parallar could not be attained even though the star were only five billions of miles off.

Could Herschell's or Lord Ross's Telescope be placed in our atmosphere, with the earth as large as the sun, the parallax of some stars could probably be attained oven upon thc anglo supplied by rotation on the home axis.

It seems to ine a conjecture founded on exceedingly strong presumptions that the sun with its one or two compeers advancing in eccentric spiral paths must have these spirals to encircle many stars progressing in curves alinear to the azis around which our solar bodies are ascending or descending as it may be termed.

I do not doubt their paths may cross each other and their pyramids of relations in crossing each other, give forth kaliadescopic colors some of which are visiblo to us as variable stars.

In the via Lactea it seems absurd to acknowledge all the abiding specs of light as proper solar systoms-It may be a kind of Heliacal matrix or foundry where cometary scavengers are pumerously generated and for long periods may be preparing to travel off in many instances far short of the countless billions of miles so easily described.

I will venture to guess, that several, if not all the planetarian bodies referred to by Herschell are Phoctonic suns hybernating by marital compact and only shorn of their brilliance for limited periods; nor is it outside of settled convictions attaching to Pythagorean Astronomy that at no distant day, a compeer of our son approaching it, will borrow our light after terrible destructions among some of the inferior planets.

After that, Herschel aud Le Verrier and Saturn will approx. imate nearer during a long night and at last an Adamic raco be planted upon thein.

Cannot Le Verrier find Laxel's comet as one of the moons of his yet unfinished planet by going back on the paths of that comot and that planet!

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Deo. 21, 1846. E. MERIAM, Esq.

Dear Sir-Fow discoveries in modern times has excited . more lively attention from the public thao Morse's Telegraph,

It seems marvellous that the Telegraph manager oan transinit his orders thousands of miles in a fow seconds by signals of motion.

Is the impulse imparted along tho wires a result of centripetal or of eeptrifugal energy! or does it express the difforenco of force existing between the collecting and the dispersing laws of matter?

The force of gravity under magpotic attraction seeks after absolute repletion while the law of segregations claims instant. ly to reach the state of negation, neithor of which conditions can be more than approximated amidst our elementary atmosphere.

If electric energy for a moment obeys contentrative tondencio, it socms only fettered that it may the better manifest its own expanding powers among atoms that oppose it.

The tree that is riven by olectricity into fragments suffers a sudden expansion of its own gaseous elements and in steam boilers the steam decomposed and ignited electrically drives the splintered boiler or shouts them liko rockets high into the air.

I know the gauge cocks of a boiler to exhibit suction of air and instantly frothy steam was extruded, tho engineer shut off tho water supply to prevent explosion, the wheels ceased moving, the fire doors were thrown open, the boat made fast, all took refuge among the trees on shoro and yet no explosion occurred.

On examination the lead connection of the steam pipes was dissolved, the water in the boilers was below the proper line along the fire-flue and little steam was found in the boilers.

The engineer stated the Grampus-low-Boat, under like circumstances, in consequence of not shutting of the cold water cast her boilers in fragments to great distances, and yet he too was soon after killed by the steam of his boiler that leaped from its bed.

This engineer Sturdivant, informed me that an irregular force obstructing the ingress of the pump supply sometimes disturbed boilers and the steam being decomposed and ignited, generally caused explosions of much more serious character than explosions froin high pressure of stcam among defective containers. In such cases, electricity and elasticity, magnetism and gravity, aaloricity and light and other properties of matter are evidently concorned with a most striking disregard of centralizing control.

Professor Hare's Calorimoter and deflagrator generates and governs these dangerous powers, checking and pointing out means whereby they may be applied for artesian borings aud tho dissolutions of rocky and other mineral masses as fonnd in mining.

An engine of four horse power applied with proper machinery for collecting electric energies, or magnetic or both together, could yield means for the defence or attacks of war ships. of fortresses and probably for the rocket propulsions of gun cotton among troops on march or in battle.

Through 'magnetic implements for increasing the intensity of magnetic developements on a multiplied system, a surprising force of electro dispersive action could be extended along iron wires for any distance.

Rapid as is the transmission of laminous impulses from the sun to the earth, if an iron wire extended between then luminous and other developements would pass along it faster than in that waving column of relations subsisting between them as at present.

So great is the atfinity between the gas called oxygen and iron, that oxygen might be suspectod to have a inetalic terugenous base as ils combustion supporting principle.

The metalic base found in chloric acid gas certainly jovites to ex. pect iron in oxygenons compounds and perhaps nickel io nitroge nous gases under peculiar circumstances.

I have observed that large beds of magnetic ore are more subject to be stricken by lightning than other Chalybiate ores, and any iron ore often struck by the electric charges becomes inagnetized. Magnetic beds

of load stone bave ihousands of polarizing points belonging to different lunips and when ground into fine dust be come obedient to antagonist polarites forming under electric impulses curious configurations.

In the Boreal lights the fitful flickerings indicate a dubious conflict between these antithetic forces and in the polarizing flirtations of luminosity when subdued by telescopic implements the same warfare bel ween opponent principles may be observed,

Now is light and gravitation be not substantive atoms, why should electric or magnetic attributes be other than properties?

But if the opposing and great primary two laws can give motion to atoms in order to adjust differences of force, why may not mere properties of matter which have obtained embodiment, to some extent free from their restraining atoms, be also subjected to motion even for the production of musical intonations as laid down by Pythagoras!

I feel perfectly convinced that by partitions in the application of the varieties of electro maguetic forces extended on the piano plan, under rational direction, that musical sounds inay be expressed.

Whoever wishes can hear the Vucanean sounds of volcanoes and the subdued mutterings of earthquakes like remote mountains sliding on their bases, or may hear in some places the strange Eoliais sounds of electro-magdelic currents passing under ground in sandstone mountains.

Indeed without the ercitations of electro-magnetism, what bells or what strings of any instrument ever uttered a single sound of musical notes

The human voice has a mechanical living organization made in exact compliance with the laws and the media ihrough which the music and the words of moral right obtain expression and admission to rational panoramas.

The living man contains an epitome of the universe of existing principle within himself and, his Physiological functions imitate in action the soundest maxims of reason intellectually exercised, while both intellectually and physiologically many demonstrations are made conceding the influence of Physical law over them.

The pulsating heart obeys a living impress of electro-galvanic force with all the tendencies for concentration and dispersion, for conservation and destruction which the same laws differently modi. fied present to us among inanimate atoms.

From the capillary venous system passes to the beart, fuids discharged from local duty, bearing along chylíferous nutriment all which after liberation from the lungs excites the counter part of the heart and is thence impelled to the brain and to the capillarystructure whence enfeebled of vitality it recommences its motion to the heart.

The brain formed of a double construction of organs, has these structures severally and jointly despatching and receiving orders that simultaneously exteud along the nervous tissures for pathegnomonic services of body and intellection.

A splendid simplicity reigns through all the complexities of nature, by the great prevalence of two laws under the wings of wliich are conveyed bundles of other lesser rules FOR BEING, and the study of philosophy aims at knowing these things as nature exhibits them to mankind.

If worlds are drawn together by agreeing relations so are per. sons by certain congruities and in like manner bostile relations may separate both.

There are congruities for generation and for the opposite, both in the physical and the living organism, and among intellectual morals agreements may become perpetual is liberated from the opponent principles.

But without comparing living capacities with physical laws it may be safely assumed that the place where equipoise of relations occurs between the moon and earth is always within the latters body and the point of like character between the sun and earth is ever within the sun's disc.

Outside of cones in space embracing the masses of any two bodies no relations of whatsoever kind extend between them and light, gravity and repellant attributes appear to decreuse directly by squares of distance and inversely by cubes of respective mase

That eminations from a Drummond light or transfers of electro. magnetic forcealong wires within our atmosphere must be affected by all surrounding influences which exist not along the transits from Globe to Globe in void space, must be considered, in all our experiments of the laboratory.

Two substances each composed of two diverse atoms placed in suitable menstrua will disintegrate and form an exchange differing greatly from the first and the severing and attracting motions yielded in making the transfer, exactly represents the diference between their forces tending to disjunction and recomposition.

That magnetic attraction concurs with weight of substance appears from the fact that while a magnetized block of iron lifts upward another piece of iron both weigh as they did previously.

It is curious that when four persons with their fingers raise a fifth, the weight of the latter, during inbalation of all the parties seems transferred into the former by soine galvanic association, so that the effort skillfully made, seems no more than lifting one's weight, when walking up stairs.

Something like this happens when a swarın of bees cluster round their companions that with slender claws hold the twig ou which they hang; and after the same manner clumps of hybernating bats in caverns, hang upon each other, suspended by the wing claws of the few attached to the side stone wall

During the marsupial exloetation the young cling to the mammac without an effort as if part and parcel of the maternal integuments.

According to the received theory of gravitation inatter at the earth's center would represent no weight centripilally and the small difference of 26 miles in favor of ibe equaloral or greatest rotary diameter forins a set oti for the lack of centrifugal tendency at the poles.

From the spherical structure of the stratified crust of the earth it seems probable there is no great increase of density after de. scending below the fields, when full play is allowed to electro-mag. netic or chemical exchanges.

Water running under the surface of the ground is supposed to
abstract part of the common electro-magnetic forces from the sur-
face, so that a person walking from a repletive point, can detect
the negative place, by means of iwiggs or metallic rods held in his
hands; or vica versa, can find the line along any ore banks by the
saine means.

It is certain living twigge lean most toward water and trees
lean toward the bill-side on which they grow.
Tho Helianthus by night bonds its flower caste , I

If a cup of water in the ground has a motion given to the water from right to left, facing the south, the circulation continues longer than if the same force had been applied in the opposite way.

Birds exposed to cold winds and rain lose that levity which belongs to the gaseous contents of their quill-feathers and cannot so well fly, nor can animals run as well after chilling their galvanic forces by drinking too much cold water.

The Gymnotus or electric cel stuns a fish it touches is living, but a dead fish flies off when touched by it and possibly the lightning bug has a like action npon the animalculæ on which it feeds.

The moon and sun light I think imparts to sea waters and fish an electro-galvanic power for emitting luminous appearances at night

Indians say sleeping in moon light impairs vision and all the nicer animal sensibilities and assert deer and cattle wiil not of choice sleep in it.

If a finger touch the tree on which Cicadian insects are hold. ing their concerts they at once stop and give attention and it is strange at how great distances a thunder-storm may be distinguished by placing the ear against a solid rock in the wall of a cave.

An epidemic constitution of the air is felt by animals and I could always distinguish by seosations from the atmosphere, wherein cholera-cases would immediately appear.

The same I can assert as to material places and rooms impreg. nated by the small pox, typhus or billious, or yellow fever, as well us some other affections having various sensible and distin guishing traits.

I cannot doubt instruments may be invented for testing tho vitiated qualities of the air imparted by combinations between peculiar chemical properties of some districts, with solar or lunar eminations.

The postures of the moon and earth affect disease and health periodically and at certain sasons the death of trees is easily brought on them and various seeds require special times in every climate to be sown or planted.

By the reciprocating influences of the places of the sun and earth the seasons are made and in conjunction with the moon, tides and ocean currents, water-spouts and storms, and the movement of springs and clouds, with the various changes in vegetable life are all preserved and exhibited.

Even comets passing through the solar system, must impart more or less electro-magnetic influences and I think it will some day be admitted that the quantity of electric action on the earth may vary daily according to exchanges made with the JUD.

In 1818 the sun had spots and in 1831 I saw many spots in August the sun's face appearing of a very blue color and in 1838 February 144h I think was a large spot and the sun's disc was very blue.

It was most probably caused by non lucept clouds of gas rising through the luminous strata, as its exterior band resembled the brighter ring around dark clouds in sun-shine.

In 1843 during January from the 12th to the middle of February the sun's face was excessively white and its rays scorching which was rucceeded by the clouds and cold of March, during the comet's appearance of that year.

li was my opinion the vegetation of the ensuing season was more luxuriant especially in the size and quantity of leaves than ever I had witnessed, whilst insects of all sorts died.

There was more electricity in the clouds thea for years be. fore and from a reasonablo estimate, I concluded not fewer than 3000 troes upon al out 6000 square miles of highlands in Tenuessee were strictly lightning that season.

The daily passage of the sun affects polarity of the needle and it is possible tbe lines oi no variation represent oquations between water and land sprfaces and iso-thermal influence between tropical and pola chemical action as well as night and day and monthly positions of the moon and the places of tho sun as it traversos its yearly orbit.

Magnetic polarity would have its importance heightened were it proven that the polar axis always encircles a fixed part of the northern sky 47 degrees in diamoter, once in 25,000 years, for, that would indicata a spiral movement of our sun around a mear fins in that rourae.

The distance, rjestar being known, the sun's motion by annual departure it, would afford an appreciable basis by which to estim solar motion,

If a magnetic telcos mile wire extended from the Cape of South America to colles crossing the equator and tho line of no magnetic varieping it is probable some curious experiments could be le its daily workings.

By parallaxes and transmitted simultaneously from these remote ?

asurements of the earth's diameter heretofore talen

be tested and the causes of variations in the action of 1

Hulum be put upon a basis for better understanding

sent. I think it?

author of the Iliad and Odyssy wus apprised of the of the needle and its use in navigation but the nautica the age did not permit its use.

If this conjeciilor irect Homer was an Egyptian Helenist and died 1106, P. C.

It is said the C for 2,500 years past knew the fact of magnetic polarity.

I have offered it: oing remarks and suggestions, not to give but to receive !" mation.

You perceive I comes electro-magnetic phenomena to be producis of the co!!.. und dispersing laws of the universe in this case con

ertain conclave properties of atoms and whilst motion i seed among these mere proporties a greater or less of { motion is also imparted to atoms which fall with

late range of such excitations. It is upon the

les that the records that you are so carefully mali

"preted dependencies in atmosphoric temperature

Amical changes in the air and earths crust will inf

be of great scientific value. The oldu!

"ctions and even Espy's rain making prodigies

harmless, while your enquiries, of the last year

hieve aroused the sleeping powers of ancient Bore

by day pursuas the course of th sun westw. tender vines and creepers !

Sous and the occident Hesperus and before tranqui a restored you must invoke and call to your aid C

Follox the old guardians of the mar# iner's helm.

Yours,

Dec. 26th, 1846. and roosting places by pidgeons covers the ground E. Meriam, Esq. :

and by occupying the same sections periodically, a Dear Sir,---You make enquiries about the wild pid- rich mould and luxurient vegetation is the necesgeon migrations of the West. Their color is of a

sary consequence, as may be observed along many uniform dove, variable among the feathers of the ridges otherwise quite sterile. head and neck according to the shades of light: the In 1807, the spring season was very mild and in ringlets and brighter shades about the neck distin. the Kentucky ridges not remote, millions of pidgeons tinguish the male-the size is between that of the had their young which overspread the country but dove and the domestic pidgeon with bright orange- their number was trifling compared with the multicolored reddish legs and their whole construction tudes that arrived from the north-west in November manifests extraordinary endurance and muscular en. covering the fields of corn and proving very destrucergy. In deep snows and when without food for tive. They soon dispersed by large divisions among weeks they become emaciated and feeble, but are the then undisturbed forests of oak and becch. very rarely found dead and I am satisfied their life I have seen at one time six or eight streaming continues longer than forty years.

flights at elevations of six to ten thousand feet and Their number now in the conntry drained by the when descending near to the earth their shadow like Mississippi River is not above ten per cent of the that of thin clouds would cover a space varying from multitude which forty years ago inhabited the same a quarter to three quarters of a mile for every stream. region. In 1805 east of the Blue Ridge-base North Their flights often continned for three days from ten Carolina, many millions had their young among small o'clock till near evening and when highest, their oak timber extending some five miles in length by passage was at the rate of forty to sixty miles per three-quarters of a mile in breadth.

hour but when near the earth their flight varied Their offspring at the lowest estimate of two for from fifteen to thirty miles per hour. They are very every couple must have exceeded five millions, after careful to avoid stormy districts and deep snows and all allowances made for the destruction by birds do not like the warm sun of the south. When flying beasts and man, as well as the casualties from tree- in dense crowds pidgeons that are shot will be conbranches falling by accidental overburdens. It is veyed forward a quarter of a mile or more before difficult to describe the confused noise of these multi- falling. tudes when going to root or retiring in search of The immediate causes of their migrations seem to food at early dawn. They disperse by flocks, be for food and suitable provisions for their expected ranging daily, for months, one hundred miles around

young. in every farm and prying among the leaves and There are a few analogies between their gregarious herbage in all forests, and eat most voraciously: If habits and those of the crane and gerse tribes The they find the weather will be very cold they either latter are more tractible and less voracious looking retreat southward or fill their craw with bitter- much more to the republican good of the whole than berry seeds which will not soon digest and this do the wild and truly savage pidgeons. they always do when preparing for very long flight. In flying so rapidly at great heights they seem to The Cornus Florida or dogwood-berry is preferred have the power of Galvanic levigation without diwith its bitter coating but in defauit of finding it, minishing their muscular energy. they take the locust-seed, the wax-nut, or the seed of Is it possible that rice-birds, psora, swallows and several pea-looking pods which is found upon shrub- martius, possess similar instincts that enables them, bery of the mountains. They select Indian-corn be- above the denser air to exert a muscular energy westfore any other food, but consume rico and all the wardly, so as to permit the rotation of the earth to other cerial products and chestnuts, chinquipins, leave them? The manner in which they appear and acorns, berries and even worms when their young disappear periodically, at wide distances round the is in need of food. I never kuew them to use poi- earth, indicate that such a suggestion has at least as sonous berries; but if they should eat laurel-berries much probability in its favor as attaches to many scitheir flesh would be very poisonous to persons caling entific theorems of our ballooning times. it.

Indeed I am not sure if Franklin and Gay Lusac I have seen them and wild-turkeys eating elder- were among us now, that, they would not catch so berries which have the effect of stupifying and ma

much of the auroral illuminescence and other terrene king thein very gentle.

levigating tendencies, as to enable the latter, in a The pidgeon when much pressed by hunger will mammoth balloon, to ride westward by night, all pick the buds from the elm-tree and ihe white ten- round the globe being only careful to carry along dril sprouts of grass or other plants just emerging enough of oxygen to preserve life in a state of hyberfrom the ground and they are especially fond of the nation. newly-sprouted grains of corn or wheat. Their flesh

Before closing I must mention a remarkable state is very dark and has a very wild flavor, always im

of the thermometer since the strong south-west wind bued more or less with the galls of nuis and acorns from 6 to 12 o'clock last night after which the de. so as to be sensible to the tasting and smelling or- gree of 54 continued as I was told from then until 8 gans even after being well cooked.

o'clock this morning. This uniformity depends in In the early seitlements of the West the immense

this instance upon currents of caloricity within the beach forests supplied pidgeons with food and resting earth's crust travelling from the south-west during retreats, while that nut had also an intoxicating effect the last three days until now the terrene heat has upon them. Indians say to subsist on the beech-nut reached its acme. When first begining the thaw without other diet causes human beings to acquire commenced fin the snow next the ground and continstrange hallucinations of intellect and I am satisfied

ued all night, although the air was below the freezing of the correctness of the remark from observing its point ten or twelve degrees. Before that an increas happifying influence upon bear and hogs that gloat ing cold for ten days was observable in the crust and on its nutritious qualities.

rocks and in such cases sooner or later the air is But the manna-feast or great jubilee for pidgeons brought into equilibriation with the temperature of was the fourteenth year periodic-seeding of canefields, the ground surface and this usually happens over occupying considerable districts, and yielding thirty tracts one hundred or more miles in breadth by five to sixty bushels, of a very perishable grain, to the hundred or eight hundred miles in south-western acre, as I conjecture,

length as I have observed for thirty years past. This This arundenacious growth springs from the seed position favors your opinions, and as I know can be and from the joints of the roots increasing in size for thoroughly proven. During the earthquakes of 1811, fourteen years, to the height of six feet to thirty feet

'12, '13, I ofteu observed cold and hot currents of and standing too thick-set for a bird to fly thrvugh it,

chemical changes belonging to the earth before being except where animals beat down paths.

manifested in the air. The head of the plant droops as soon as the cane

Yours, begins to die, (which is universal to the seeding-lime,) the whole fields presenting the yellow appearance of

30th December, 1846. ripened oats, millet-looking brownish seed talling to

E. MERIAM, Esq. to the ground, sends forth a little worm leaving a hole in the seed, like that in English peas. Although the Dear Sir ;-The weather continues very mild, the grain is so very perishable multitudes of pidgeons snow having all disappeared. Mr. M. will report the and other animated things subsist on it during the state of the thermometer and rain guage for the month. period of its becoming ripe.

At two o'clock to-day the therinometer was 72. In The iinmeuse quantity of manure left at brooding my letter of the 20th I added for its close, on the

27th some remarks respecting one cause for equili. brations of temperature depending npon equations of heat in the earths crust and in the air. Sometimes a very fluctuating temperature of atmosphere loses that character when the surface of the ground and the air approximate an equation no matter which is the gainer of caloricity. The same remark applies to the differences of temperature between extensive water surfaces and superambient air. In low latitudes the earth and water give caloric to the air rushing down from the superior parts of the atmosphere as every one has remarked, but it is not so well known, that the heated earth of the tropies sends off much heat, as if by electro magnetic impulse, through the rocks and all the crust of the ground, in a northern course on one side of the equator. The motion of the gulph stream represent this impellent power in the ocean deeps, but at times, a no less potent influence makes its impres. sion, rapidly extending caloric through the dry land from south to north in general. I have observed however that this current of heat always is deflected north-eastward on coming into contact with the fractured stratifications reaching in parrallism with our mountain chains this side of the Mississippi river.

This it is which, as stated in a former letter to you, utters strong and plaintive sounds within the horizontal sand stone strata of the cumberland mountain table plains.

Włen in these cases the cloud making vapours and air extract from the earth these electro magnetic forces, they thunder in the skies and at once a negative or cold making current rushes from the north east along the line which had been occupied by the travel. ling heat until repelled by new calorescent forces from the south west. With tendencies of like kind the air is also affected and sometimes the earths crust has very little correspondence with it, but finally an equi. poise must happen between them. Hurricanes are certainly put in motion by the agencies referred to but all their great energies are insignificant when compared with the force of oceanic currents or with the same Dynamies yielding earthquakes. Sea water in consequence of holding iron and cloride of sodium possesses great aptitudes for these potent agencies and I am convinced the same will be abstracted at a future day, and applied to the propulsion of vessels over its sur. face. You perceive the close connection of the equili. brations between what is called positive and negative polarizations and caloricity and cold, with those equalibriums, at which for two years you have been del. ving with I think much practical success. I should be glad you could behold a summer storm, after dry weather in the Sequatchee valley of Tennessee. A valley, 150 miles long, averaging eight miles wide and bounded on both sides by the mural precipices of horizontal sandstone 800 feet thick, overlaying four to six hundred feet of lime stone composing the cumberland mountain, whose table plains on the south east are 12 miles broad and on the north west 30 miles in width. The walls of the two sides appear as if they would form a jointed seam if brought together. The valley is gently rolling with a lime stone base, over which a rich soil, with sand stone boulders and water worn pieces are intermingled. The Tennessee river in passing into this valley 14 miles across the eastern mountain plain, narrows its bed froin near half a mile, to 100 and 200 yards, and is overlooked by the mountain acclivities on either side whilst its whirling waters carry's through boats at the rate of ten or twelve miles per hour. It is in this ralley the reverberations of ihunder echoing three or four times with enlargeing force and volume cause the earth to shake revulsively, at every repetition of the echo, as if it were some vast leviathan breathing forth its voice. Under these cliffy ancient sheets of sand. stone great amounts of nitre have entered the crumb. ling stone, here also abounds the bituminous coal and feruginous sands forming the grand magazine of thunders. I was always surprised that these great coal deposits exposed at the surface in some places, have not been ignited by lightning. Perhaps defended as coal generally is against the lightning I might, with like propriety, express surprise that a leyden jar or a franklin rod is not disolved by lightning: Although this coal has remains of pine bark and imprints of rosin on the upper surfaces of its lamina, yet I think it was no more composed out of wood than the adjacent sand-stone was composed out of reeds of which specimens very large and short pointed, may be found imbedded or cast in it. Depend upon it geologists have much yet to learn astronomically before they

can expound all that belongs to these formations. vapporized, and with absolute certainty will again be and there is another plant of the equisatia kind. In the Geologists talk of watery sediments as if those substan- subjected to like vicissitudes. The Bible expressly adjoining limestone, Corrals, trilobites, and teretraces had found ocean heds as level as the sea surface states that while the present rain bow seasons prevail tula with other shells appear all of which plates toon which to make stratifications. Some parts of the no more foods will drown the earth, but has not set gether are about 100 feet in thickness. globe in northern Europe, Asia, South America and forth the state of things after the rain-bow pledge is

Second Group of Rocks 900 Feet, the secondary lime stone regions drained by the removed by exterior and interior heats, such as all Mississippi were level and yet remain so, but who can may see have occurred in time past. If understood,

A massive redist, limestone having its fissures filled

with seams of iron and white carbonate of lime, very believe that the granitic base whether fluidized or the scriptures never require wrong interpretation to solid could remain every where level at its surface defend their veracity. Yours,

close grained and composed of comminuted corrals when first sediments of so great a depth were made.

and minute particles of shells, the stratification is very The mountain limestone and many classes of rocks

January 1st, 1847. imperfect and sometimes twenty or thirty feet thick, appear to have been fashioned like snow and glazier E. MERIAM, Esq.

the whole composing a wall 350 feet in thickness, masses collecting and sliding down hills and sometimes Dear Sir.— I will present you a sketch of the rocky

with another somewhat similar layer 550 feet in forced up hills existing from the date of lime rocks. formations at Saltville, Virginia, beginning at the river

thickness. These two masses as it by grinding on Directly by the eastern əscarpment of this great bed level and thence by the Salt Works ascending to the

each other, have comminuted parcels of Llue debris of horizontal sand stone, water worn sand-stone summit of Walker's mountain two miles distant

of limestone between them alongside of which a boulders are levelled over the under lying ridges and in a South-East direction without respect to minor

layer of calcarous malier, like fish eggs, 8 or 12 inmore ancient surface, but are always carried down the dislocations and short irregular synclinal and anticli

ches thick may be seen. Above this range is scattered valley south-westward or across it and never up. It nal dislodgments the rocks for the entire distance

much mungenese and iron ore which, like the ochrus forms the coves out of which they were disrupted. have a mean inclination of about 35 to 40 degrees

yellow unctuous stone, has probably been thrown The flinty structure east and parralel with the their upper face bearing South Eastward on the

there by the rush of water currents from neighbormountain lime and sand-stone appear to have been North West side of all the ridges and mountains of

ing places. Along the Eastern side, this great bed of 80 heated as to attain honey comb forms, by trans- this region. The Stratafied rocks present broken

rock presents an ashy color and is curly and very disfusing their purer melted parts into cold water, for edges thereby exposing all kinds to the influence of

torted withbeautiful lime crystals attaching to its retithese pebbles of various colours are all smooth and cold and rain and hence that exposure has been made

culated structures and next to it is a black heary iron rounded and also shivered as if by hasty cooling. In very fertile while the Southern exposure is com

flint rock jutting out and often passing into the black the subjacent every old limestone of the inountain

shale and gypsum locks. paratively barren by reason of the superior stratum kind are numerous flint nodules well cemented, and if being sand or other free stone. The seams of black

Third Group 400 Feet, such a thing is possible, the carbonic acid being lost slate yellow and gray indurated shales with layers I now enter the saliferous structure about Saltville, a lithic acid seems to have entered and transmuted of calcareous clays sand and debris compose the S. the black shale referred to is hard and britte, fracturlimestone into a coarse flint, but I must say that I am Eastern bank of the river whilst the sand stonos

ing like inferior stone coal into angular figures, with a neither a chemist or geologist, as you may perceive. I composing the upper crust of Clynch Mountain form

strong bituminous smeli. The lime rocks in thin strata can know when a corn field wants rain and by like the North Western bank. Opposite Saltville on the and the shale of yellow cast stretching along its process of inspecting soine geological treatises of deface of Clynch Mountain a grand debacle has forced

eastern side is a composition of unbroken shells all cidedly high merits, I cannot avoid thinking that a its way out forming a large cove or pot three miles standing nearly perpendicularly with some yellow revisal is much needed to invigorate and bring geology in circumference the rocks of great size being forced and redish indurated slate clays. The whole not exon to perfection. Unquestionably in this vicinity many through a narrow opening to the river, which has

ceeding 200 feet in thickness, but the thin slaty clays stratified rocks have synclinal and anticlinal positions conveyed them down the stream with a great force of various colors black, red, green, ash-colored, blue, by original formation over rough primary rocks, hills in ancient days. This cove is walled in by high cliffs

and variegated with white, are all interstratified with and mountains ; and on steep parts have slided down of white and brown sandstones and the red sandstone ;

the saliferous and gypseous deposits in tortuous wavhill over and under each other with all the confusion the first abraded and the whole average thickness is ing lines and lamina. The saliferous deposit at this and turning over which may be witnessed among near 800 feet. The white sand may be crumbled from

place extends a mile in length and half a mile in sheets of ice taking passage on the turbed whirling the rock by the finger, but the yellowish and dingy, greatest breadth the surface presenting a peaty, bogwaters of the Mississippi.

brown sandstone is hard, clinky. and easily separated gy black soil which in dry weather will burn. This There inust have been times past when more water into oblong squares having two acute angled corners. Hat is surrounded on the East side by cliffy lime and existed than now and also periods when very little of At some points the red sandstone is clifly and above

pure Burr millstone walls curling round at either end any water remained in contact with the earths surface, 300 feet in thickness containing spirifers and toward the above perpendicular black shale formathe causes of which facts belong to astronomical minute shells shaped like a half bean and others still

tion thus giving it the appearance of a crater. In science.

less, resembling split peas. Below the red sandstone this flat artisian borings 800 10 900 feet passed through The moon gives indications of having no water on lies a thin stratum of lime stone, laminated and white,

solid gypsum and the variegated clays before mentionit at present and yet telescopic vision may hereafter with all the shelly remains common to the similar ed, without other solid rocks, except iron stone nofind evidence that water once belonged to that orb. very thin plates, overlaying the great horizontal se

dules and erritic pieces of Burr stone from the EastIf all the water from the earth were removed it is pos- condary limestone of Tenuessee, Alabama, and Ken. ern hill, wiiere it is embedded in massive limestone, sible its solid rotundity would be too deficient for tucky. Various deeper limestone stratas are exposed in thickness varying from 20 to 100 feet. The upper diurnal rotation and as a sequence its most projecting in the cove, the cliff-edges of which, is more than part of the red salt rock is above 200 feet under the surface would remain all the year facing the sun- three miles in circuit and is twenty-seven hundred surface and has been excavated 70 feet -and bored and it is geologically probable the centre of such feet at the most elevated points above the river at into 30 or 40 feet deeper where it lies against the projection would belong to a present high latitude Saltville, two miles distant from this Mountain sum- rock walls on the Western side, it has particles of in northern Asia or Europe. I feel well assured mit. I would remark that Clynch, and Walker's blue and green marl sand sparsely commingled in it that time will afford proof that a similar state of Mountain, extend probable two hundred miles in with layers of white and crystaline gypsum passing things may arise at a calculable date hereafter. After length, and apparently they stand upon a trough of through it and masses of gypsum rock lying around such an event the next tenantry of the globe would linestone shales, and slate of immense thickness it on the West and on the East. The water passing find many relics to examine more curious than saurian which crop out near the mountains on both sides through it is saturated or is uniformly 24-25ths of the skeletons. The theory that thirty miles from the boldly forcing up the superstratal rocks, thus forming salometer. The salt by fire evaporations contains sarface the whole interior world is in a state of the western and eastern appending ridges with the two per cent of foreign substance mostly sulphate of fusion, seems as absurd as to believe that no sections narrow valleys extending along these ranges of ele. lime with a trace of oxyde of iron, but no trace of of it can be in a heated or fused condition, Artesian vation. If the remark be well founded it indicates

muriate of lime and magnesia. This salt rock is on borings seventeen hundred feet in depth on the that an opposing force from the South-East met a the late William King's estate, situated about 37° N., Kanbawa exhibit no evidence of increasing heat be- greater disrupting force from the North West during and the Meridian line leaves Abingdon_10 miles yond the slight chemical results arising from the ad- the upheavings of these rocks which happened sub- West and about ten miles thence to the Tennessee mission of air and water into contact with substances sequently to the sand deposits chiefly composing the line at the iron mountains, not far from the North Calong excluded from freedom of space, in which such mountain crusts. As it is reasonably certain that the

rolina Western boundary. In the flat where this affinities might have some play. The opening of granitic body of the earth never had a level water-liko salt rock lies, are contained numerons mammoth mines at many places induces increased heat and ad

sarface it may be inferred that sand formation in skeletons in the soft white gypsum near the surface mission of air or salt waters into craters, no doubt oceans are not spread alike everywhere, but as ocean the bones seem to be a gypseous mass, but in a slate excites volcanic action. It is however very clear that beds of mountain granite would influence and direct sea formation 15 feet under the surface a large tusk seemthe tenure by which attraction holds ascendancy over currents these would deposite sands along and upon ed but little changed and the enamel of the molar the opposite dispersive attributes of terene matter is such elevations. But being no Geologist I will de- teeth is bright, smooth and sound as when first buried too frail and slight to admit of a general chemical in- scribe as above promised the character of the rocks in the soil. The line of gypsum continues 16 miles condesence throughout the interior earth. Under such from the Holston River level, on a line by Saltville to up the River valley with the variegated earths as a state of fludity the earths crust would wave like a the summit of Walker's Mountain elevated eight or found at Saltville and the solid plaster has been peneballoon filling with gas. At the periods of spring nine hundred feet above Saltville.

trated 675 feet at its upper boundary. The red forand neap-tides while volcanic vents might pour out

First Group of Rocks, 100 Feet,

mation called sandstone extends far East and West, oceans of lava as greater freedom for action was ob- Along the Saltville side of the river bank, black and also the line of Burr stone but salt has not else. tained. But the whole theory is replete with obsolete- slates, yellow and olive indurated shales and grey where been found, there is a doubt whether this ism unsuited to the advancing, condition of geology calcarious slaty clays in which Apicorinities with red sandstone in the once deep crevice between and astronomy, yet from exterior influences similar to leaves and barrel-shaped joints are very abundant Walker's and Clynch Mountains now containing the those which disentegrate comets on approaching the standing somewhat inclined in their original place of saliserous deposit, has any connection with that red Sun there is no doubt, but that much of the earths growth, also stems of the Sigellaria flattened, one sandstone deposit, to be seen near the tops of those mass has been at various times not only fused but to three inches wide, having leat-eyelit impressions mountains. The saliferous deposit may belong to a

lower deposit geologically speaking by several thou- the English Oolite deposite, but far lower down. sand feet and yet the valley depression may be at the These are true remarks as time will develope. place to which the sinking of the Clynch formation But on the Atlantic and Gulf coasts the analogues of would rightfully place it. The copper ridge beyond the above mentioned European deposites are all reClynch Mountain seems not to be the same contini

gularly met with. I think the gniess and mica schist nous red stratum which here is called the red sand.

system are uot far below the series of rocks described stone formation. But I will proceed to describe the at Saltville, and I think that the saliferous deposite rocks ascending from Saltville to the top of Walker's was obtained out of the detritus of the red sand-stone Mountain and here I may mention that besides the of the Walker and Clynch Mountains at the time of sub ridges at the base of Clynch and Walker's Moun. their elevation. I am convinced then a hot water tain there are between them five rows of conic hills lake held in solution the muriate of soda and was from 100 to 300 feet high, extending along the valley evaporated in a short and troublous time” during in parallel lines, presenting at a distance the appear- whích time free sulphuric acid was abundantly pourance of large mounds or pyramids.

ed fourth among the lime rocks, expelling the carFourth Group 1500 Feel.

bouic acid and compelling the formation of the gyps. Next after the saliferous deposit the vast mas

esous rock commingling with the muriate of soda. sive lime rocks badly or but little stratified occur

The slates and thes guies and the scists below wore holding in front the Burr millstone Alinty rock, out of

not then so affected as to expel their mineral oils and

form stone-coal at this place. I repeat, future inquiwhich in times past hot waters flowed making tra

ries will sustain the outlines of the imperfect views I vestine alabaster deposits and even yet giving out cool springs which produco gortre, and give to the

am able to give you regarding these old mineral ice formed from the waters a cerulian green color.

rocks. I have not time to copy. In haste, with resThe thickness of this limestone is not uniform, but

pect, Yours abundantly, &c., may be set down as 800 feet to the magnesian water cement limestone and this last with its cherty lime

EARTHQUAKE IN SCOTLAND. stones may be rated at 700 feet.

A smart shock of earthquake has been experienced
Fifth Group 1800 Feet.

over a pretty extensive district in the centre of Scot

land. About midnight on Tuesday, November 24th. The next commencos with the Burr millstone.

Crieff, Perth, Dundee, Cupar Fife and Dollar, had all as did the last, but it is of inferior quality and differ

felt the shock, which appears to have occurred alently situated from the last having above it a blueish

most simultaneously throughout the extensive tract massive system of limestone containing ammonites or

of country which comprehends these towns.thocerelites and other shells with a contigious irre

Scotsman. gular vein or plate of barytic earth and dark thin

Dollar.-Shortly after twelve o'clock this mornplated masses of slate, over which is scattered quartz

ing (Wednesday) we experienced a smart shock of crystals in great profusion stretching up and down the valley. Above this, lie thick beds of imperfect bourhood since the 23rd of October, 1839. It woke

earthquako, the first that has been felt in this neighslate and what is called alluminous earth, the whole group at least 1800 feet in thickness reaching the

many sleepers from their slumbers, and seemed as middle part of Walker's Mountain and the lower

far as we could judge, to vibrate from west to east. side of ihe red earth and shale and sand called red

By persons recumbent in upper appartments the

motion of the houses was distinctly and somewhat sandstone. There is also coarse grey and redish

alarmingly felt. The night was damp, dark and marble stretching 50 to 100 feet in thickness along

cloudy, with scarce a breeze stirring, and of very the mountain's base.

mild temperature-exactly such as the night of the Sixth Group 800 Feci,

23rd of October, 1839. The barometer had risen The red marl and sand may then be rated at 400 feet during the day to about 29,44, but this morning it has and above it are strata of slaty clays earths and another

again sunk a little. Altogether the character of the olive green stratum composed and almost entirely weather this autumn has resembled very much that of a kind of shell casts some of which yet retain

of 1839; a great quantity of rain (about twenty. a purple coloring matter. If part of a hickory nut

seven inches since July)--the sky for the last month on one of its oblate sides were cut off leaving a

charged with close, dense dark clouds—the atmoscurling over projecting at one end, the figure would

phere soft, mild, hazy and dripping, with an irregular represent these casts, which appear in the same soft

barometer, taking sudden and extreine movements. deposit upon Clynch Mountain. Above these the

It is to be remarked that these earthquakes happen brown hard sounding sand rock some white sand stone and much silicified sand stone appears capping generally in October and November, during the

night,

when there is little or no wind, with soft rain falling, the mountain and all these may together amount

the earth's surface being charged heavily with moisto 800 more feet. The total estimate without ac.

ture.--Scotsman. curate admeasurement I mako 5,500 feet of super

VIOLENT Shock or EARTHQUAKE.-On the night incunbent rock, What kind of rock is below the

of the 24th Nov., a few minutes before 12 o'clock, a boring in the vicinity I have no means of know

shock of Earthquake was felt here of greater intening. Yours, &c.

sity and longer duration than any remembered. The

state of the atmosphere at the time was calm and

JANUARY 20, 1847. beautifully clear. Early on the previous morning a E. Merian, Esq.

very heavy rain had fallen, which had cleared the Dear Sir-I inclose my eleventh letter to you to air and softened the temperature, and the following gratify yonr request of last winter to let you know day was unseasonably fine and mild, the thermometer something of the geological features around Saltville standing about 52 degrees. At nine o'clock, evening At Kanhawa, 1,500 or 1.600 feet below the surface, it had fallen to 42 degrees, the barometer indicating they pass saliferous coal bearing deposit and soon no 29-50 inches, the greatest cold during the night was more salt will there be inade by reason of exhaustion. 36 degrees, and the barometer inclined to rise, standHere we are on the edge of a thin coal bearing stra- ing next morning at 29-51 inches. The feeling of intum that runs 4,000 feet uuder the lowest artesian dividuals, during the shock, depended greatly on boring. (rely on this) at Kanhawa, connected with their situation. It is most generally described as which there or here is no saliferous bed at all. This I being rather tremulous than undulating, and in high say on the knowledge I have of the western car- tenements heavy articles of furniture were very vioboniferous system, saving however the possibility lently shaken, bells were rung, and crockery ware that from the first a granite elevation obtained under overturued. Every family was alarmed, and many the superior coal system at Kanhawa, which of rashed out to the streets uuder the impression that course might prevent the full development of the se- their houses were falling. condary limestone formation. On the blne ridge Such as were walking at the time describe the near us only silicious and wind or wave deposited ground az sbaken under thoir feet, much like the tresand-stone crowns the plutonic and volcanic granites

mulous motion in steamboats. The duration of the forming the summit range of that mountaiu. Here shock, by all accounts, must have been from fifteen at Saltville, no appearances called the tertiary Eocene, to twenty seconds, although the fears of many namyocene and plaocene formations exist, the chalk turally led them to think it longer. It extended as system too is absent, and only very slight traces of far north as our accounts yesterday reached, and the lowest Oolite system is met with of a kini deep along the line of the Grampians it seems to have been in the secondary formation and not the same with particularly severe. Our correspondent at Crieff

writes last night thus :

“ At 12 o'clock, perhaps two minutes after it, a low rumble, resembling distant thunder, but one which a practised ear could at once detect to be the herald of an earthquake, was heard. For five or six seconds it approached nearer and nearer and waxed louder and louder ; then came a heavy underground knock or two, then a sensible upheaving and down. falling, accompanied by a violent shaking of every. thing on the surfaee, and the thunder-like noise, continuing, for six or eight seconds, died away in the distance. This may not have been the heaviest shock of earthquake that has occurred in Crieff for the last fifty years, but it certainly was a very smart one, and caused many a timid heart to quake. The air before and at the time of the shock was calm and still, but a short time thereafter a fresh breeze sprang up.Pertshire Courier.

OBSERVATIONS. From Brooklyn Evening Star, of Nov. 24, 1846. The highest temperature yesterday was 52°, from 11 to 12. The temperature at 6 P. M. was 48°-at which it continued till 6 this inorning"- [Tuesday morning, Nov. 24.]

From the Star, Friday, Nov. 27. “ The highest temperature Tuesday, was 55. at ? P. M. At 6 in the evening, 50; at 8 and 9, 49o ; and at 10 and 11,50°; and Wednesday morning, at 6,7, and 8, 49—with a storm following the equilibrium of Tuesday morning."

From the Star of Saturday, Nov. 28. “Tas WEATHER.--The temperature recorded by me, and noted in the Star, is that indicated by metooric wires of a peculiar construction. In warm weather these wires accord with the ordinary thermometer, but in cold weather they differ from ten to twenty degrees, and probably may vary more than this during intense cold ; but notwithstanding this disagreement, they mark all convulsions with uner. ring accuracy. Long continued and carefully record. ed observations may enable me to understand tire disagreement and explain it, but at present it is a mystery. The wires support an appendage of a large loadstone from the Magnetic Cove in Arkansas. They extend high into the atinosphere, one pointing to the north-east, and the other to the south-west; are pointed with tin lined with copper wire which connects with tho iron rods descending into the water, resting in and beneath the surface of the ground.

“ The highest temperaturo indicated by these me teoric wires on Wednesday, was, from 11 to 12. 52; on Thursday, 46, at both ends of the day; on Friday, 494 from 12 M. to 5 P. M.; on Wednesday evening at 7, 47-at 8, 44-and at 9, 46 ; on Friday morning at 6, 46 ; on Friday evening at 8, 49--at 9, 50; OR Saturday morning at 6, 50—et 7, 52-at 8, 51.

“The ordinary thermometer indicated as follows : Wednesday morning at 9, 39—3 P. M., 39—9, 29; Thursday morning at 6,26—at 9, 28-at 12 M. and 3 P. M., 32—at 4, 291-from 5 to 6, 28-at 7, 27—from 8 to 9, 263; on Friday morning at 6, 243-at 1 P. M. 32-at 2, 31--at 3, 30-from 4 to 8, 314--at 9, 32; Saturday morning at 6, 36-at 7 and at 8, 371.

“Snow fell at half-past six on Wednesday evening. Snow clouds were in the west on Friday morning before sunrise, and overhead at 2 in the afternoon.

" Another disturbance in the atmosphere is indicated by equilibriums and rise of temperature in the nighi time.

E. M. "Saturday morning."

It will be seen by comparing the above recorded observations, published here on the above dates with the accounts from the Scotch papers, that the earthquake, at 3000 miles distant, was accurately indicated by the wires, here. It will be seen by the record published on Saturday, of the state of the wires on Wednesday evening the 25th, that they were at 46 from 9 P. M. Wednesday to Thursday morning. On referring to my detailed record, I find that 46° continued till 12 noon of Thursday, and 7 P. M. of Thursday was at 46°, and continned at that until 9 A. M. on Friday. Here the two entire equilibriums are a perfect accord.

The Steamer Atlantic was wrecked on the night of the 25th, and destroyed on the morning of the 26th, on Long Island Sound.

E. MERIAM.

*

FROM PROFESSOR OLMSTED

OF

BY

OLYSTKD.

YALE COLLEGE. We have received from the learned Professor whose name heads this notice a printed copy of the work of his pen

entitled Thoughts on the Discovery of Le Verrier's Planet,which we take the liberty to re-print on account of its excellence and the high esteem we entertain for the gifted author.

From the New-Englander, for Jan. 1847. THOUGHTS ON THE DISCOVERY OF LE

VERRIER'S PLANET.

PROTESSOR At a sitting of the French Academy in June last. a paper was presented written by M. Le Verrier, a young astronomer of Paris, the object of which was to prove that there exists, in the solar system, a planet hitherto unknown, situated at double the distance of Uranus from the sun, which on the first of January, 1847, would be at or near a point in the ecliptic whose longitude is 325 degrees. This extraordinary hypothesis has resently been verified by the actual observation, with the telescope, of the body in question. It was first seen by Dr. Galle, a distinguished astronomer of Berlin, on the 23d of September, and it has since been seen at London, and more recently at various observatories in our own country.

Although in apparent brightness this stranger is equal only to a star of the eighth magnitude, and consequently must remain forever invisible to the naked eye, yet the telescope invests it with all the characters of a planet, readily distinguishing it from fixed stars by its perceptible disk, and by its motion around the snin, which, though comparatively slow, is still vastly greater than belongs to any of the stars. It requires more than two hundred years to complete its circuit ; and although its exact magnitude is not yet determined, yet enough is known to assure us that it is one of the largest of the planets, and more than a hundred times as large as the earth.

This discovery, by theory alone, of a body hidden 80 deep in the abyss of space, and until now invisible from the creation of ihe world, determining not only its existence but its exact place among the stars, proclaims most audibly the perfection at which phy. sical astronomy has arrived ; and it invests truth it. self with a solemn grandeur, when we think how far into the recesses of nature it will conduct the mind, that diligently follows its leadings, even in the secret retirement of the closet.

The method of investigation, although laborious and intricate, is not difficnlt to be understood, but may be described in very simple terme. The planet Uranus (Herschel) has been long known to be subject to certain irregularities in its revolution around the sun, not accounted for by all the known causes of perturbation. The tables constructed with the greatest care for any particular epocb, from observations on the planet, guided and corrected by the theory of universal gravitation, do not accurately give its place at periods of a few years either before or after that time. In some cases the deviation from the true place, as determined by observation, has been two minutes of a degree-a quantity indeed which seems small, but which is still far greater than occurs in the case of the other planets, Jupiter and Saturn for ex, ample, and far too great to satisfy the extreme accuracy required by modern astronomy. From 1781, when Herschel discovered this planet, to 1821, observations had been accumulated on its motions for forty years, a period abundantly sufficient to afford the necessary data for determining the illiptic elements of its orbit. Indeed, there were older observations than these, scattered along a whole century; for before this body was determined to be a planet, it had been recognized and its places assigned as a star of the sixth magnitude. In the year 1821, Bouvard. a French mathematician of eminence, compiled tables of this planet, availing himself of the most recent, and what he deemed the most perfect observations, and allowing for the perturbations occasioned by the attractions of the other planets, chiefly those of Saturn and Jupiter, which on acconnt of their great masses, as well as their proximity to Uranus, would

of course more or less disturb his motion. Bouvard about a common centre of gravity, which they do in himself, however, was struck with the fact that his exact obedience to the law of universal gravitation. tables were incompetent to represent the actual Secondly, the resistance of a supposed ether, or places of the planet, as it had been seen by the older subtle elastic medium, diffused through space, has astronomers, and he even suggested the possibility of been assigned as the cause of the pbenomenon in an unknown planet, whose hidden action upon Ura- question. But, were this the cause, we might exnus occasioned the disagreement in question.

pect to see it manifested in the motions of the other For the benefit of our readers as have not given planets, and the more as their motions are more rapid their attention to subjects of this kind, it may be pre- than those of Uranus. The existence of such a memised, that, in accordance with the law of universal dium has indeed been inferred, in consequence of cergravitation, every body in the solar system is attracted tain effects manifested in the movements of Encke's by and attracts every other; that such large bodies comet; but it may be easily conceived, that an exas Saturn and Jupiter exert a powerful influence in ceedingly light body would indicate such a resistance, disturbing other members of the system, their effect while a dense body like the planets would not. A being sensibly felt upon the earth, although, when particle of down may experience resistance, when nearest, the former is distant from us about eight moving swiftly through a medium, where a musket hundred and the latter about four hundred millions of ball would not be sensibly affected. miles ; that this disturbing force exercised by one Thirdly, the hidden influence in question has been body of the system over the others, is proportioned ascribed to a great satellite of Uranus, hitherto un. to its quantity of matter, or inass, and is therefore so discovered. But the perturbations occasioned by much greater in the sun than in one of the planets, such a satellite would be of short period, completing only because the sun contains so much more matter a cycle during the revolution of the satellite about its thad the planet ; that, in the same body, the power primary, which would occupy but a sbort time, of attraction diminishes rapidly as the distance is in. whereas the changes in the perturbations occasioned creased, being four times less when the distance is by the cause under considerarion are exceedingly trebled; or, as astronomers express it, the attraction slow. Moreorer, in order to produce effects on Uradiminishes in proportion as the square of the distance nus so great as those to be accounted for, a very large is increased. In order, therefore, to form tnbles satellite, would be required, of such a magnitude, inwhich shall truly represent the motions of a planet deed, that it would not fail to be seen with the telerevolving aronnd the sun in an elliptical orbit, it is

scope. necessary not only to estimate the differeut velocities Fourthly, the disturbing influence of a comet, has which the body would have on account of its diffor. also been proposed to account for the irregularities of ent distances from the sun, arising from the eccen. Uranus. But comets have never been known to extricity of its orbit, but to allow also for the united ef- ert any appreciable influence upon the motions of the fects of all the disturbing influences (perturbations). planets. The comet of 1770 passed among the satwhich result from tho actions of the other bodies of ellites of Jupiter, without sensibly disturbing their the system, some of which tend to accelerate it, movements, -a proof that the quantity of matter in others to retard it, and others still to turn it out of its these bodies is inconceivably small. Nor, from the path. Thus the exact place of a ship, even when eccentricity of the orbits of comets, could we suppose carried forward by a uniform breeze, can not be de. a comet to linger in the immediate vicinity of Uranus termined from the reckoning, and only after due al- so long, as the perturbations which it is assumed to aclowance is made for all the curronts that have either count for are known to have existed. conspired with or opposed its progress. Before such Finally, the suspicion of the existence of a planet, allowances can be made and applied, the exact lying beyond the orbit of Uranus, did not originate weight of each of the bodies in the system must be with Le Verrier, but had been entertained by several known; and it is one of the sublime results at which eminent astronomers, for twenty-five years before the modern astronomy has arrived, that the planets have subject engaged his attention. But merely to conjecin fact been weighed as in a balance, and their re- ture the existence of such a body, or even to assert spective quantitios of matter ascertained with as its existence without proof, implies very little ; bnt to much precision, as that of an ordinary article of mer. establish its existence by satisfactory evidence, and chandise.

still more, to tell where it lies among the myriads of Now the only planets in the solar system heretofore stars, to weigh it, to assign its distance from the sun, known to disturb the motions of Uranus, are Saturn and the period of its revolution—these are the points and Jupiter, the other planets being so far off and so of difficulty, and it is the successful solution of the small, that their attraction is insensible. In construct- problem under all these various aspects, that constiing tables, therefore, to represent the motions of Ura- tutes the glory of this youthful astronomer. nus, or by means of which its exact place in its orbit Lo Verrier did not undertake the formidable task can at any time be calculated, it was only deemed of determining these points, until he had fully proved, necessary to allow for the disturbing influences of that the disagreement between theory and observathese two great planets. But after making the al. tion in the motions of Uranus, was no fault of the talowances required, still, after a few years, Uranus bles themselves; that they were truo at least as far was found by observation to deviate very materially as they went. For this purpose he submitted to a from the calculated place. Some other cause, there- new and laborious discussion the observatiens, both fore, must disturb its motions besides the attractions old and new, which had ever been upon this body, of Jupiter and Saturn. Several hypotheses have from the time when its place was first noted, on the been at different times proposed to account for the supposition that it was a fixed star, down to the prodisagreement in question.

sent time. He re-calculated the formulae which af. First, it has been urged that at so remote a distance forded the basis of tables of Bouvard, and scrutinized from the sun as eighteen undred millions of miles, (the every possible source of error in these tables. Some distance of Uranus,) the law of gravitation itself loses errors were indeed detected; but after making full somewhat of its constancy or uniformity ; consequent- allowance for these, the actual place of the planet, as ly tables founded on this law, as those of Uranus are, determined by observation, was still widely at variwould uot give resnlts exactly conformable to obser- ance with that resulting from calculation. For examvation. This hypothesis is not only unsupported by ple, in 1838, after calculating the maximum error any evideace, but is at variance with all known facts which could exist in the tables,-an amount probably in astronomy: Halley's comet, for example, during much greater than actually does exist.—he showed its late revolution, departed to a distance from the that it could not exceed 30 seconds of space, wheresun equal to twice that of Uranus, (about 3,600,000.- as the disagreement between the calculated and ob000 of miles) yet on its return in 1835, after an ab- served places of the planet, was 125 seconds; and, in sence of more than seventy-five years, it was true to 1831, this difference amounted to 188 seconds, of the time appointed, having come to its perihelion which 140 could not be explained, without admitting within a day of the time assigned to it by calculations some other disturbing influence than that arising from founded on the law of universal gravitation. More- the sun, Jupiter and Saturn. over, we have independent proof of the unerring uni. Assuming, then, the existence of an undiscovered formity of this law, when extended to distances far planet, the first inquiry was, where is it situated at greater than that ofUranus from the sun, or than that what distance from the sun-and in what point of the of Halley's comet in the aphelion, since it is found

starry heavens ? to prevail even among the stars, regulating the revo- First, it could not be below Saturn, that is, belution of sun around sun, as is now proved concerning tween Saturn and the sun, because then it would disthe binary stars of which the two members revolve turb Saturn more than it did Uranus, whereas the

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