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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 not 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 feather in respect to gravitating connection with stars and as a sequence the luminous effluence from a star directed upon our globe, may stand as a star-image upon a cone of relations, stopping far from us, and thus we see only this image which serves to direct tellescopic 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 parallax 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 even upon the angle supplied by rotation on the home axis.

It seems to me 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 exlinear to the axis 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 visible to us as variable stars. In the via Lactea it seems absurd to acknowledge all the abiding specs of light as proper solar systems-it may be a kind of Heliacal matrix or foundry where cometary scavengers are numerously 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 san approaching it, will borrow our light after terrible destructions among some of the inferior planets.

After that, Herschel aud Le Verrier and Saturn will approximate nearer during a long night and at last an Adamic race be planted upon them.

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 comet and that planet!

E. MERIAM, Esq.

Dec. 21, 1846.

Dear Sir-Fow discoveries in modern times has excited a more lively attention from the public than Morse's Telegraph. It seems marvellous that the Telegraph manager oan transmit his orders thousands of miles in a few seconds by signals of

motion.

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

The force of gravity under magnetic attraction seeks after absolute repletion while the law of segregations claims instantly to reach the state of negation, neither of which conditions can be more than approximated amidst our elementary atmosphere.

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

The tree that is riven by electricity 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 shoots them like rockets high into the

air.

I knew the gauge cocks of a boiler to exhibit suction of air and instantly frothy steam was extruded, the engineer shut off the 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 shore 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-tow-Boat, under like circumstances, in consequence of not shutting off 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 from high pressure of steam among defective containers. In such cases, electricity and elasticity, magnetism and gravity, caloricity and light and other properties of matter are evidently concerned 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 and the dissolutions of rocky and other mineral masses as found 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 them 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 affinity between the gas called oxygen and iron, that oxygen might be suspectod to have a metalic ferugenous base as its combustion supporting principle.

The metalic base found in chloric acid gas certainly invites to expect iron in oxygenons compounds and perhaps nickel in nitroge nous gases under peculiar círcumstances.

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 magnetized. Magnetic beds of load stone have thousands 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 between opponent principles may be observed,

Now if 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 magnetic forces extended on the Piano plan, under rational direction, that musical sounds may 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 Eolian sounds of electro-magnetic currents passing under ground in sandstone mountains.

Indeed without the excitations 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 through 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 heart, fluids discharged from local duty, bearing along chyliferous 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 capillary structure 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 extend 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 which 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 persons by certain congruities and in like manner hostile 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 if 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 decrease directly by squares of distance and inversely by cubes of respective mass.

That eminations from a Drummond light or transfers of electromagnetic force along 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 difference 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 inhalation of all the parties seems transferred into the former by some 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 swarm of bees cluster round their companions that with slender claws hold the twig on 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 exfoetation 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 matter at the earth's center would represent no weight centripitally and the small difference of 26 miles in favor of the equatoral or greatest rotary diameter forms a set off 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-magnetic or chemical exchanges.

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

same means.

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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 eel stuns a fish it touches if living, but a dead fish flies off when touched by it and possibly the lightning bug has a like action npon the animalcula 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 holding 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 sensations from the atmosphere, wherein cholera-cases would immediately appear.

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

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

nar 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

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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 1833 February 14th I think was a large spot and the sun's disc was very blue.

It was most probably caused by non lucent 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 succeeded by the clouds and cold of March, during the comet's appearance of that year.

It 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 than for years before and from a reasonablo estimate, I concluded not fewer than 3000 trees upon about 6000 square miles of highlands in Tennessee were stricken by lightning that season.

The daily passage of the sun affects polarity of the needle and it is possible the lines of no variation represent equations between water and land surfaces and iso-thermal influence between tropical and polar chemical action as well as night and day and monthly positions of the moon and the places of the sua 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 diameter, once in 25,000 years, for, that would indicate a spiral movement of our sun around a mean lie in that course.

The distance of

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If a magnetic teleph wire extended from the Cape of South America to carlakes crossing the equator and the line of no magnetic variation it is probable some curious experiments could be te

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electro-magnetic phenomena to be and dispersing laws of the universe certain conclave properties of atoms faced among these mere properties a f motion is also imparted to atoms bediate range of such excitations. les that the records that you are so nected dependencies in atmospheric emical changes in the air and earths be of great scientific value. Mctions and even Espy's rain making es harmless, while your enquiries, of have aroused the sleeping powers of Notus and the occident Hesperus and le restored you must invoke and call Follox the old guardians of the marYours,

E. MERIAM, Esq.:

Dec. 26th, 1846.

Dear Sir,-You make enquiries about the wild pidgeon migrations of the West. Their color is of a uniform dove, variable among the feathers of the head and neck according to the shades of light: the ringlets and brighter shades about the neck distintinguish the male-the size is between that of the dove and the domestic pidgeon with bright orangecolored reddish legs and their whole construction manifests extraordinary endurance and muscular energy. In deep snows and when without food for weeks they become emaciated and feeble, but are very rarely found dead and I am satisfied their life continues longer than forty years.

Their number now in the country drained by the Mississippi River is not above ten per cent of the multitude which forty years ago inhabited the same region. In 1805 east of the Blue Ridge-base North Carolina, many millions had their young among small oak timber extending some five miles in length by three-quarters of a mile in breadth.

Their offspring at the lowest estimate of two for every couple must have exceeded five millions, after all allowances made for the destruction by birds beasts and man, as well as the casualties from treebranches falling by accidental overburdens. It is difficult to describe the confused noise of these multitudes when going to roost or retiring in search of food at early dawn. They disperse by flocks, ranging daily, for months, one hundred miles around in every farm and prying among the leaves and herbage in all forests, and eat most voraciously. If they find the weather will be very cold they either retreat southward or fill their craw with bitterberry seeds which will not soon digest and this they always do when preparing for very long flight. The Cornus Florida or dogwood-berry is preferred with its bitter coating but in defauit of finding it, they take the locust-seed, the wax-nut, or the seed of several pea-looking pods which is found upon shrubbery of the mountains. They select Indian-corn before any other food, but consume rice and all the other cerial products and chestnuts, chinquipins, acorns, berries and even worms when their young is in need of food. I never knew them to use poisonous berries; but if they should eat laurel-berries their flesh would be very poisonous to persons eating it.

I have seen them and wild-turkeys eating elderberries which have the effect of stupifying and making them very gentle.

The pidgeon when much pressed by hunger will pick the buds from the elm-tree and the white tendril sprouts of grass or other plants just emerging from the ground and they are especially fond of the newly-sprouted grains of corn or wheat. Their flesh is very dark and has a very wild flavor, always imbued more or less with the galls of nuts and acorns so as to be sensible to the tasting and smelling organs even after being well cooked.

In the early settlements of the West the immense beach forests supplied pidgeons with food and resting retreats, while that nut had also an intoxicating effect upon them. Indians say to subsist on the beech-nut without other diet causes human beings to acquire strange hallucinations of intellect and I am satisfied of the correctness of the remark from observing its happifying influence upon bear and hogs that gloat on its nutritious qualities.

But the manna-feast or great jubilee for pidgeons was the fourteenth year periodic-seeding of canefields, occupying considerable districts, and yielding thirty to sixty bushels, of a very perishable grain, to the acre, as I conjecture.

This arundenacious growth springs from the seed and from the joints of the roots increasing in size for fourteen years, to the height of six feet to thirty feet and standing too thick-set for a bird to fly through it, except where animals beat down paths.

The head of the plant droops as soon as the cane begins to die, (which is universal to the seeding-time,) the whole fields presenting the yellow appearance of ripened oats, millet-looking brownish seed falling to to the ground, sends forth a little worm leaving a hole in the seed, like that in English peas. Although the grain is so very perishable multitudes of pidgeons and other animated things subsist on it during the period of its becoming ripe.

The immeuse quantity of manure left at brooding

and roosting places by pidgeons covers the ground and by occupying the same sections periodically, a rich mould and luxurient vegetation is the necessary consequence, as may be observed along many ridges otherwise quite sterile.

In 1807, the spring season was very mild and in the Kentucky ridges not remote, millions of pidgeons had their young which overspread the country but their number was trifling compared with the multitudes that arrived from the north-west in November covering the fields of corn and proving very destructive. They soon dispersed by large divisions among the then undisturbed forests of oak and becch.

I have seen at one time six or eight streaming flights at elevations of six to ten thousand feet and when descending near to the earth their shadow like that of thin clouds would cover a space varying from a quarter to three quarters of a mile for every stream. Their flights often continned for three days from ten o'clock till near evening and when highest, their passage was at the rate of forty to sixty miles per hour but when near the earth their flight varied from fifteen to thirty miles per hour. They are very careful to avoid stormy districts and deep snows and do not like the warm sun of the south. When flying in dense crowds pidgeons that are shot will be conveyed forward a quarter of a mile or more before falling.

The immediate causes of their migrations seem to be for food and suitable provisions for their expected young.

There are a few analogies between their gregarious habits and those of the crane and geese tribes The latter are more tractible and less voracious looking much more to the republican good of the whole than do the wild and truly savage pidgeons.

In flying so rapidly at great heights they seem to have the power of Galvanic levigation without diminishing their muscular energy.

Is it possible that rice-birds, psora, swallows and martius, possess similar instincts that enables them, above the denser air to exert a muscular energy westwardly, so as to permit the rotation of the earth to leave them? The manner in which they appear and disappear periodically, at wide distances round the earth, indicate that such a suggestion has at least as much probability in its favor as attaches to many scientific theorems of our ballooning times.

Indeed I am not sure if Franklin and Gay Lusac were among us now, that, they would not catch so much of the auroral illuminescence and other terrene levigating tendencies, as to enable the latter, in a mammoth balloon, to ride westward by night, all round the globe being only careful to carry along enough of oxygen to preserve life in a state of hyber

nation.

Before closing I must mention a remarkable state of the thermometer since the strong south-west wind from 6 to 12 o'clock last night after which the degree of 54 continued as I was told from then until 8 o'clock this morning. This uniformity depends in this instance upon currents of caloricity within the earth's crust travelling from the south-west during the last three days until now the terrene heat has reached its acme. When first begining the thaw commenced in the snow next the ground and continued all night, although the air was below the freezing point ten or twelve degrees. Before that an increas ing cold for ten days was observable in the crust and rocks and in such cases sooner or later the air is brought into equilibriation with the temperature of the ground surface and this usually happens over tracts one hundred or more miles in breadth by five hundred or eight hundred miles in south-western length as I have observed for thirty years past. This position favors your opinions, and as I know can be thoroughly proven. During the earthquakes of 1811, '12, '13, I often observed cold and hot currents of chemical changes belonging to the earth before being manifested in the air.

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27 th some remarks respecting one cause for equili brations of temperature depending upon 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 frac tured 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.

When 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 travelling 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 equipoise 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 surface. 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 delving 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 from 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 valley the reverberations of thunder 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 sandstone great amounts of nitre have entered the crumbling 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. Geologists talk of watery sediments as if those substances had found ocean beds as level as the sea surface on which to make stratifications. Some parts of the globe in northern Europe, Asia, South America and the secondary lime stone regions drained by the Mississippi were level and yet remain so, but who can believe that the granitic base whether fluidized or solid could remain every where level at its surface when first sediments of so great a depth were made.

The mountain limestone and many classes of rocks appear to have been fashioned like snow and glazier masses collecting and sliding down hills and sometimes forced up hills existing from the date of lime rocks. Directly by the eastern escarpment of this great bed of horizontal sand stone, water worn sand-stone boulders are levelled over the under lying ridges and more ancient surface, but are always carried down the valley south-westward or across it and never up. It forms the coves out of which they were disrupted.

The flinty structure east and parralel with the mountain lime and sand-stone appear to have been so heated as to attain honey comb forms, by transfusing their purer melted parts into cold water, for these pebbles of various colours are all smooth and rounded and also shivered as if by hasty cooling. In the subjacent every old limestone of the mountain kind are numerous flint nodules well cemented, and if such a thing is possible, the carbonic acid being lost a lithic acid seems to have entered and transmuted limestone into a coarse flint, but I must say that I am neither a chemist or geologist, as you may perceive. I can know when a corn field wants rain and by like process of inspecting some geological treatises of decidedly high merits, I cannot avoid thinking that a revisal is much needed to invigorate and bring geology on to perfection. Unquestionably in this vicinity many stratified rocks have synclinal and anticlinal positions by original formation over rough primary rocks, hills and mountains; and on steep parts have slided down hill over and under each other with all the confusion and turning over which may be witnessed among sheets of ice taking passage on the turbed whirling waters of the Mississippi.

There must have been times past when more water existed than now and also periods when very little of any water remained in contact with the earths surface, the causes of which facts belong to astronomical science.

The moon gives indications of having no water on it at present and yet telescopic vision may hereafter find evidence that water once belonged to that orb. If all the water from the earth were removed it is possible its solid rotundity would be too deficient for diurnal rotation and as a sequence its most projecting surface would remain all the year facing the sunand it is geologically probable the centre of such projection would belong to a present high latitude in northern Asia or Europe. I feel well assured that time will afford proof that a similar state of things may arise at a calculable date hereafter. After such an event the next tenantry of the globe would find many relics to examine more curious than saurian skeletons. The theory that thirty miles from the surface the whole interior world is in a state of fusion, seems as absurd as to believe that no sections of it can be in a heated or fused condition, Artesian borings seventeen hundred feet in depth on the Kanhawa exhibit no evidence of increasing heat beyond the slight chemical results arising from the admission of air and water into contact with substances long excluded from freedom of space, in which such affinities might have some play. The opening of mines at many places induces increased heat and admission of air or salt waters into craters, no doubt excites volcanic action. It is however very clear that the tenure by which attraction holds ascendancy over the opposite dispersive attributes of terene matter is too frail and slight to admit of a general chemical incondesence throughout the interior earth. Under such a state of fludity the earths crust would wave like a balloon filling with gas. At the periods of spring and neap-tides while volcanic vents might pour out oceans of lava as greater freedom for action was obtained. But the whole theory is replete with obsoleteism unsuited to the advancing condition of geology and astronomy, yet from exterior influences similar to those which disentegrate comets on approaching the Sun there is no doubt, but that much of the earths mass has been at various times not only fused but

vapporized, and with absolute certainty will again be subjected to like vicissitudes. The Bible expressly states that while the present rain bow seasons prevail no more floods will drown the earth, but has not set forth the state of things after the rain-bow pledge is removed by exterior and interior heats, such as all may see have occurred in time past. If understood, the scriptures never require wrong interpretation to defend their veracity. Yours,

E. MERIAM, Esq.

*

January 1st, 1847.

Dear Sir.-I will present you a sketch of the rocky formations at Saltville, Virginia, beginning at the river level and thence by the Salt Works ascending to the summit of Walker's mountain two miles distant in a South-East direction without respect to minor dislocations and short irregular synclinal and anticlinal dislodgments the rocks for the entire distance have a mean inclination of about 35 to 40 degrees their upper face bearing South Eastward on the North West side of all the ridges and mountains of this region. The Stratafied rocks present broken edges thereby exposing all kinds to the influence of cold and rain and hence that exposure has been made very fertile while the Southern exposure is comparatively barren by reason of the superior stratum being sand or other free stone. The seams of black slate yellow and gray indurated shales with layers of calcareous clays sand and debris compose the S. Eastern bank of the river whilst the sand stones composing the upper crust of Clynch Mountain form the North Western bank. Opposite Saltville on the face of Clynch Mountain a grand debacle has forced its way out forming a large cove or pot three miles in circumference the rocks of great size being forced through a narrow opening to the river, which has conveyed them down the stream with a great force in ancient days. This cove is walled in by high cliffs of white and brown sandstones and the red sandstone; the first abraded and the whole average thickness is near 800 feet. The white sand may be crumbled from the rock by the finger, but the yellowish and dingy brown sandstone is hard, clinky. and easily separated into oblong squares having two acute angled corners. At some points the red sandstone is cliffy and above 300 feet in thickness containing spirifers and minute shells shaped like a half bean and others still less, resembling split peas. Below the red sandstone lies a thin stratum of lime stone, laminated and white, with all the shelly remains common to the similar very thin plates, overlaying the great horizontal secondary limestone of Tennessee, Alabama, and Kentucky. Various deeper limestone stratas are exposed in the cove, the cliff-edges of which, is more than three miles in circuit and is twenty-seven hundred feet at the most elevated points above the river at Saltville, two miles distant from this Mountain summit. I would remark that Clynch, and Walker's Mountain, extend probable two hundred miles in length, and apparently they stand upon a trough of limestone shales, and slate of immense thickness which crop out near the mountains on both sides boldly forcing up the superstratal rocks, thus forming the western and eastern appending ridges with the narrow valleys extending along these ranges of elevation. If the remark be well founded it indicates that an opposing force from the South-East met a greater disrupting force from the North West during the upheavings of these rocks which happened subsequently to the sand deposits chiefly composing the mountain crusts. As it is reasonably certain that the granitic body of the earth never had a level water-like surface it may be inferred that sand formation in oceans are not spread alike everywhere, but as ocean beds of mountain granite would influence and direct sea currents these would deposite sands along and upon such elevations. But being no Geologist I will describe as above promised the character of the rocks from the Holston Rive level, on a line by Saltville to the summit of Walker's Mountain elevated eight or nine hundred feet above Saltville.

First Group of Rocks, 100 Feet, Along the Saltville side of the river bank, black slates, yellow and olive indurated shales and grey calcarious slaty clays in which Apicorinities with leaves and barrel-shaped joints are very abundant standing somewhat inclined in their original place of growth, also stems of the Sigellaria flattened, one to three inches wide, having leaf-eyelit impressions

and there is another plant of the equisatia kind. In the adjoining limestone, Corrals, trilobites, and teretratula with other shells appear all of which plates together are about 100 feet in thickness.

Second Group of Rocks 900 Feet,

A massive redish. limestone having its fissures filled with seams of iron and white carbonate of lime, very close grained and composed of comminuted corrals and minute particles of shells, the stratification is very imperfect and sometimes twenty or thirty feet thick, the whole composing a wall 350 feet in thickness, with another somewhat similar layer 550 feet in thickness. These two masses as it by grinding on each other, have comminuted parcels of blue debris of limestone between them alongside of which a layer of calcarous matter, like fish eggs, 8 or 12 inches thick may be seen. Above this range is scattered much mangenese and iron ore which, like the ochrus yellow unctuous stone, has probably been thrown there by the rush of water currents from neighboring places. Along the Eastern side, this great bed of rock presents an ashy color and is curly and very distorted withbeautiful lime crystals attaching to its reticulated structures and next to it is a black heavy iron flint rock jutting out and often passing into the black shale and gypsum 10cks.

Third Group 400 Feet,

I now enter the saliferous structure about Saltville, the black shale referred to is hard and brittle, fracturing like inferior stone coal into angular figures, with a strong bituminous smeli. The lime rocks in thin strata and the shale of yellow cast stretching along its eastern side is a composition of unbroken shells all standing nearly perpendicularly with some yellow and redish indurated slate clays. The whole not exceeding 200 feet in thickness, but the thin slaty clays of various colors black, red, green, ash-colored, blue, and variegated with white, are all interstratified with the saliferous and gypseous deposits in tortuous waying lines and lamina. The saliferous deposit at this place extends a mile in length and half a mile in greatest breadth the surface presenting a peaty, boggy black soil which in dry weather will burn. This flat is surrounded on the East side by cliffy lime and pure Burr millstone walls curling round at either end toward the above perpendicular black shale formation thus giving it the appearance of a crater. In this flat artisian borings 800 to 900 feet passed through solid gypsum and the variegated clays before mentioned, without other solid rocks, except iron stone nodules and erritic pieces of Burr stone from the Eastern hill, where it is embedded in massive limestone, in thickness varying from 20 to 100 feet. The upper part of the red salt rock is above 200 feet under the surface and has been excavated 70 feet and bored into 30 or 40 feet deeper where it lies against the rock walls on the Western side, it has particles of blue and green marl sand sparsely commingled in it with layers of white and crystaline gypsum passing through it and masses of gypsum rock lying around it on the West and on the East. The water passing through it is saturated or is uniformly 24-25ths of the salometer. The salt by fire evaporations contains two per cent of foreign substance mostly sulphate of lime with a trace of oxyde of iron, but no trace of muriate of lime and magnesia. This salt rock is on the late William King's estate, situated about 37° N., and the Meridian line leaves Abingdon 10 miles West and about ten miles thence to the Tennessee line at the iron mountains, not far from the North Carolina Western boundary. In the flat where this salt rock lies, are contained numerons mammoth skeletons in the soft white gypsum near the surface the bones seem to be a gypseous mass, but in a slate formation 15 feet under the surface a large tusk seemed but little changed and the enamel of the molar teeth is bright, smooth and sound as when first buried in the soil. The line of gypsum continues 16 miles up the River valley with the variegated earths as found at Saltville and the solid plaster has been penetrated 675 feet at its upper boundary. The red formation called sandstone extends far East and West, and also the line of Burr stone but salt has not elsewhere been found, there is a doubt whether this red sandstone in the once deep crevice between Walker's and Clynch Mountains now containing the saliferous deposit, has any connection with that red sandstone deposit, to be seen near the tops of those mountains. The saliferous deposit may belong to a

lower deposit geologically speaking by several thousand feet and yet the valley depression may be at the place to which the sinking of the Clynch formation would rightfully place it. The copper ridge beyond Clynch Mountain seems not to be the same contininous red stratum which here is called the red sandstone formation. But I will proceed to describe the rocks ascending from Saltville to the top of Walker's Mountain and here I may mention that besides the sub ridges at the base of Clynch and Walker's Mountain there are between them five rows of conic hills from 100 to 300 feet high, extending along the valley in parallel lines, presenting at a distance the appearance of large mounds or pyramids.

Fourth Group 1500 Feet.

Next after the saliferous deposit the vast massive lime rocks badly or but little stratified occur holding in front the Burr millstone flinty rock, out of which in times past hot waters flowed making travestine alabaster deposits and even yet giving out cool springs which produce gortre, and give to the ice formed from the waters a cerulian green color. The thickness of this limestone is not uniform, but may be set down as 800 feet to the magnesian water cement limestone and this last with its cherty limestones may be rated at 700 feet.

Fifth Group 1800 Feet.

The next commences with the Burr millstone. as did the last, but it is of inferior quality and differently situated from the last having above it a blueish massive system of limestone containing ammonites or thocerelites and other shells with a contigious irregular vein or plate of barytic earth and dark thin plated masses of slate, over which is scattered quartz crystals in great profusion stretching up and down the valley. Above this, lie thick beds of imperfect slate and what is called alluminous earth, the whole group at least 1800 feet in thickness reaching the middle part of Walker's Mountain and the lower side of the red earth and shale and sand called red sandstone. There is also coarse grey and redish marble stretching 50 to 100 feet in thickness along

the mountain's base.

Sixth Group 800 Feet,

The red marl and sand may then be rated at 400 feet and above it are strata of slaty clays earths and another olive green stratum composed and almost entirely of a kind of shell casts some of which yet retain a purple coloring matter. If part of a hickory nut on one of its oblate sides were cut off leaving a curling over projecting at one end, the figure would represent these casts, which appear in the same soft deposit upon Clynch Mountain. Above these the brown hard sounding sand rock some white sand stone and much silicified sand stone appears capping the mountain and all these may together amount to 800 more feet. The total estimate without accurate admeasurement I make 5,500 feet of superincumbent rock. What kind of rock is below the boring in the vicinity I have no means of knowing. Yours, &c.

E. MERIAM, Esq.

JANUARY 2d, 1847.

Dear Sir-I inclose my eleventh letter to you to gratify your request of last winter to let you know something of the geological features around Saltville At Kanhawa, 1,500 or 1,600 feet below the surface, they pass saliferous coal bearing deposit and soon no more salt will there be made by reason of exhaustion. Here we are on the edge of a thin coal bearing stratum that runs 4,000 feet uuder the lowest artesian boring, (rely on this) at Kanhawa, connected with which there or here is no saliferous bed at all. This I say on the knowledge I have of the western carboniferous system, saving however the possibility that from the first a granite elevation obtained under the superior coal system at Kanhawa, which of course might prevent the full development of the secondary limestone formation. On the blue ridge near us only silicious and wind or wave deposited sand-stone crowns the plutonic and volcanic granites forming the summit range of that mountain. Here at Saltville, no appearances called the tertiary Eocene, myocene and plaocene formations exist, the chalk system too is absent, and only very slight traces of the lowest Oolite system is met with of a kind deep in the secondary formation and not the same with

the English Oolite deposite, but far lower down. These are true remarks as time will develope. But on the Atlantic and Gulf coasts the analogues of the above mentioned European deposites are all regularly met with. I think the gniess and mica schist system are uot far below the series of rocks described at Saltville, and I think that the saliferous deposite was obtained out of the detritus of the red sand-stone of the Walker and Clynch Mountains at the time of their elevation. I am convinced then a hot water lake held in solution the muriate of soda and was evaporated in a "short and troublous time" during which time free sulphuric acid was abundantly poured fourth among the lime rocks, expelling the carbonic acid and compelling the formation of the gyps. esous rock commingling with the muriate of soda. The slates and thes guies and the scists below were not then so affected as to expel their mineral oils and form stone-coal at this place. I repeat, future inquiries will sustain the outlines of the imperfect views I am able to give you regarding these old mineral rocks. I have not time to copy. In haste, with respect, Yours abundantly, &c.,

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EARTHQUAKE IN SCOTLAND.

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A smart shock of earthquake has been experienced over a pretty extensive district in the centre of Scotland. About midnight on Tuesday, November 24th. Crieff, Perth, Dundee, Cupar Fife and Dollar, had all felt the shock, which appears to have occurred almost simultaneously throughout the extensive tract of country which comprehends these towns.—--Scotsman.

DOLLAR. Shortly after twelve o'clock this morning (Wednesday) we experienced a smart shock of earthquake, the first that has been felt in this neighbourhood since the 23rd of October, 1839. It woke many sleepers from their slumbers, and seemed as far as we could judge, to vibrate from west to east. By persons recumbent in upper appartments the motion of the houses was distinctly and somewhat alarmingly felt. The night was damp, dark and cloudy, with scarce a breeze stirring, and of very mild temperature-exactly such as the night of the 23rd of October, 1839. The barometer had risen during the day to about 29,44, but this morning it has again sunk a little. Altogether the character of the weather this autumn has resembled very much that of 1839; a great quantity of rain (about twentyseven inches since July)-the sky for the last month charged with close, dense dark clouds-the atmosphere soft, mild, hazy and dripping, with an irregular barometer, taking sudden and extreme movements. It is to be remarked that these earthquakes happen generally in October and November, during the night, when there is little or no wind, with soft rain falling, the earth's surface being charged heavily with moisture.-Scotsman.

VIOLENT SHOCK OF EARTHQUAKE-On the night of the 24th Nov., a few minutes before 12 o'clock, a shock of Earthquake was felt here of greater intensity and longer duration than any remembered. The state of the atmosphere at the time was calm and beautifully clear. Early on the previous morning a very heavy rain had fallen, which had cleared the air and softened the temperature, and the following day was unseasonably fine and mild, the thermometer standing about 52 degrees. At nine o'clock, evening it had fallen to 42 degrees, the barometer indicating 29-50 inches, the greatest cold during the night was 36 degrees, and the barometer inclined to rise, standing next morning at 29-51 inches. The feeling of individuals, during the shock, depended greatly on their situation. It is most generally described as being rather tremulous than undulating, and in high tenements heavy articles of furniture were very violently shaken, bells were rung, and crockery ware overturned. Every family was alarmed, and many rushed out to the streets under the impression that their houses were falling.

Such as were walking at the time describe the ground as sbaken under their feet, much like the tremulous motion in steamboats. The duration of the shock, by all accounts, must have been from fifteen to twenty seconds, although the fears of many naturally led them to think it longer. It extended as far north as our accounts yesterday reached, and along the line of the Grampians it seems to have been 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 downfalling, accompanied by a violent shaking of everything 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 520, from 11 to 12. The temperature at 6 P. M. was 48°—at which it continued till 6 this morning"-[Tuesday morning, Nov. 24.]

From the Star, Friday, Nov. 27.

"The highest temperature Tuesday, was 554 at 2 P. M. At 6 in the evening, 50; at 8 and 9, 49°; 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.

"THE WEATHER.-The temperature recorded by me, and noted in the Star, is that indicated by meteoric 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 unerring accuracy. Long continued and carefully recorded observations may enable me to understand the 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 atmosphere, one pointing to the north-east, and the other to the south-west; are pointed with tin lined with copper wire which connects with the iron rods descending into the water, resting in and beneath the surface of the ground.

"The highest temperature indicated by these meteoric wires on Wednesday, was, from 11 to 12, 52; on Thursday, 46, at both ends of the day; on Friday, 49 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; on 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, 294-from 5 to 6, 28-at 7, 27-from 8 to 9, 26; on Friday morning at 6, 244-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, 374.

"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 night time.

"Saturday morning."

E. M.

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 at noon of Thursday, and 7 P. M. of Thursday was at 46°, and continued 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

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.

BY PROFESSOR OLMSTED.

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 sun, 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 so deep in the abyss of space, and until now invisible from the creation of the world, determining not only its existence but its exact place among the stars, proclaims most audibly the perfection at which physical astronomy has arrived; and it invests truth itself 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 difficult to be understood, but may be described in very simple terms. 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 epoch, 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 example, 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 account of their great masses, as well as their proximity to Uranus, would

of course more or less disturb his motion. Bouvard himself, however, was struck with the fact that his tables were incompetent to represent the actual places of the planet, as it had been seen by the older astronomers, and he even suggested the possibility of an unknown planet, whose hidden action upon Üranus occasioned the disagreement in question.

For the benefit of our readers as have not given their attention to subjects of this kind, it may be premised, that, in accordance with the law of universal gravitation, every body in the solar system is attracted by and attracts every other; that such large bodies as Saturn and Jupiter exert a powerful influence in disturbing other members of the system, their effect being sensibly felt upon the earth, although, when nearest, the former is distant from us about eight hundred and the latter about four hundred millions of miles; that this disturbing force exercised by one body of the system over the others, is proportioned to its quantity of matter, or mass, and is therefore so much greater in the sun than in one of the planets, only because the sun contains so much more matter than the planet; that, in the same body, the power of attraction diminishes rapidly as the distance is increased, being four times less when the distance is trebled; or, as astronomers express it, the attraction diminishes in proportion as the square of the distance is increased. In order, therefore, to form tables which shall truly represent the motions of a planet revolving around the sun in an elliptical orbit, it is necessary not only to estimate the different velocities which the body would have on account of its different distances from the sun, arising from the eccentricity of its orbit, but to allow also for the united effects of all the disturbing influences (perturbations) which result from the actions of the other bodies of the system, some of which tend to accelerate it, others to retard it, and others still to turn it out of its path. Thus the exact place of a ship, even when carried forward by a uniform breeze, can not be determined from the reckoning, and only after due allowance is made for all the currents that have either conspired with or opposed its progress. Before such allowances can be made and applied, the exact weight of each of the bodies in the system must be known; and it is one of the sublime results at which modern astronomy has arrived, that the planets have in fact been weighed as in a balance, and their respective quantities of matter ascertained with as much precision, as that of an ordinary article of merchandise.

Now the only planets in the solar system heretofore known to disturb the motions of Uranus, are Saturn and Jupiter, the other planets being so far off and so small, that their attraction is insensible. In constructing tables, therefore, to represent the motions of Uranus, or by means of which its exact place in its orbit can at any time be calculated, it was only deemed necessary to allow for the disturbing influences of these two great planets. But after making the allowances required, still, after a few years, Uranus was found by observation to deviate very materially from the calculated place. Some other cause, therefore, must disturb its motions besides the attractions of Jupiter and Saturn. Several hypotheses have been at different times proposed to account for the disagreement in question.

First, it has been urged that at so remote a distance from the sun as eighteen undred millions of miles, (the distance of Uranus,) the law of gravitation itself loses somewhat of its constancy or uniformity; consequently tables founded on this law, as those of Uranus are, would uot give results exactly conformable to observation. This hypothesis is not only unsupported by any evidence, but is at variance with all known facts in astronomy. Halley's comet, for example, during its late revolution, departed to a distance from the sun equal to twice that of Uranus, (about 3,600,000.000 of miles) yet on its return in 1835, after an absence of more than seventy-five years, it was true to the time appointed, having come to its perihelion within a day of the time assigned to it by calculations founded on the law of universal gravitation. Moreover, we have independent proof of the unerring uniformity of this law, when extended to distances far greater than that of Uranus from the sun, or than that of Halley's comet in the aphelion, since it is found to prevail even among the stars, regulating the revolution of sun around sun, as is now proved concerning the binary stars of which the two members revolve

about a common centre of gravity, which they do in exact obedience to the law of universal gravitation.

Secondly, the resistance of a supposed ether, or subtle elastic medium, diffused through space, has been assigned as the cause of the phenomenon in question. But, were this the cause, we might expect to see it manifested in the motions of the other planets, and the more as their motions are more rapid than those of Uranus. The existence of such a medium has indeed been inferred, in consequence of certain effects manifested in the movements of Encke's comet; but it may be easily conceived, that an exceedingly light body would indicate such a resistance, while a dense body like the planets would not. A particle of down may experience resistance, when moving swiftly through a medium, where a musket ball would not be sensibly affected.

Thirdly, the hidden influence in question has been ascribed to a great satellite of Uranus, hitherto undiscovered. But the perturbations occasioned by such a satellite would be of short period, completing a cycle during the revolution of the satellite about its primary, which would occupy but a short time, whereas the changes in the perturbations occasioned by the cause under consideration are exceedingly slow. Moreover, in order to produce effects on Uranus so great as those to be accounted for, a very large satellite, would be required, of such a magnitude, indeed, that it would not fail to be seen with the telescope.

Fourthly, the disturbing influence of a comet, has also been proposed to account for the irregularities of Uranus. But comets have never been known to exert any appreciable influence upon the motions of the planets. The comet of 1770 passed among the satellites of Jupiter, without sensibly disturbing their movements, a proof that the quantity of matter in these bodies is inconceivably small. Nor, from the eccentricity of the orbits of comets, could we suppose a comet to linger in the immediate vicinity of Uranus so long, as the perturbations which it is assumed to account for are known to have existed.

Finally, the suspicion of the existence of a planet, lying beyond the orbit of Uranus, did not originate with Le Verrier, but had been entertained by several eminent astronomers, for twenty-five years before the subject engaged his attention. But merely to conjecture the existence of such a body, or even to assert its existence without proof, implies very little; but to establish its existence by satisfactory evidence, and still more, to tell where it lies among the myriads of stars, to weigh it, to assign its distance from the sun, and the period of its revolution-these are the points of difficulty, and it is the successful solution of the problem under all these various aspects, that constitutes the glory of this youthful astronomer.

Le Verrier did not undertake the formidable task of determining these points, until he had fully proved, that the disagreement between theory and observation in the motions of Uranus, was no fault of the tables themselves; that they were true at least as far as they went. For this purpose he submitted to a new and laborious discussion the observatiens, both old and new, which had ever been upon this body, from the time when its place was first noted, on the supposition that it was a fixed star, down to the present time. He re-calculated the formula which af forded the basis of tables of Bouvard, and scrutinized every possible source of error in these tables. Some errors were indeed detected; but after making full allowance for these, the actual place of the planet, as determined by observation, was still widely at variance with that resulting from calculation. For example, in 1833, after calculating the maximum error which could exist in the tables,-an amount probably much greater than actually does exist,-he showed that it could not exceed 30 seconds of space, whereas the disagreement between the calculated and observed places of the planet, was 125 seconds; and, in 1831, this difference amounted to 188 seconds, of which 140 could not be explained, without admitting some other disturbing influence than that arising from the sun, Jupiter and Saturn.

Assuming, then, the existence of an undiscovered planet, the first inquiry was, where is it situated-at what distance from the sun-and in what point of the starry heavens ?

First, it could not be below Saturn, that is, between Saturn and the sun, because then it would disturb Saturn more than it did Uranus, whereas the

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