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BY MRS. L. H. SIGOURNEY.

The commerce of the world. The mother-realm VIEW FROM GRISWOLD HILL,

Sends on its lide her daily embassies,

While France invokes the potency of steam,
ON STATEN ISLAND, N. Y."

To wing her message. From his ice-clad pines
The Scandinavian--the grave, turbaned Turk,
The Greek mercurial, even the hermil-sons

of sage Confucius, like the sea-bird, spread
Earth, sea and sky,-in richest hues array'd,- Their pinions toward this city of the West,
How spreads the glorious panorama round, - That like a money-changer for the earth
As from the casement of a princely dome Siis in her temple-dome. Yon ocean-gate,
We revel in its charms. From this bold height, With telegraphic touch, doth chronicle
O'er wood-erown'd hill, and mountain thinly veil'd, The rushing tide of sea-worn emigrants,
Villa and spire, and castellated roof,

Sick, sad, or famished. With what anxious eyes How glide the soft heams of the westering sun They scan the coast, that gives the stranger bread., To sleep with ocean blue.

Perchance, a grave. And he, who ventureih forth Here, at our side The willing prisoner of some white-winged ship, Frowns Fort Knyphausen, o'er whose ruind base Leaving his native land, perchance, to seek Close-woven cedars stretch their arras dark, Hygeia o'er i he wave, perchance, to test Hiding the bastions, whence in olden time, What spells do linger round the classic climes The whiskerd Hessian, bought with British gold, That woke his boyhood's dream,-how fails bis Aim'd at my country's heart.

heart With fairy grace,

As the strong hills of Never-Sink withdraw New-Jersey's shores expand. Hillock and grove, Their misty guardianship. Speech may not tell, Hamlet and town, and lithe promontory,

For well I know its poverty to paint Engird this islet, as a mother clasps

The rapture, when the homeward glance descries A beauteous daoghter. But the opposing straits, with patriot love, that clime, whose novelties, With their deep line of indentation, bar

Whose forms of unimagined life, eclipse
The full embrace. Broad spreads the billowy bay, The worn-out wonders of an Older World
Forever peopled by the gliding sail,

That ever, with ils ghostly finger, points
From the slight speck where the rude fisher toils, To things that were.
To that, which, like a mountain, treads the wave,-

Oh great and solemn Deep!Or those, that mor'd by latent fires, compel

Profound enchanter of the musing thought, The awe-struck flood.

Release my strain, that to this beauteous Isle See,- from its northern home

So long a visitant, my thanks may flow, The bold, unswerving Hudson, that hath burst

Warm, though inadequate. Autumnal tints The barrier of his palisades, to gaze

Float in full brilliance over copse and grove, On all this wondrous beauty, and to swell

Where erst the Red Man rested on his bow, With lordly tribute, what it views with pride.

Wrapp'd in brief reverie, 'mid the haunts* he lov'd, Behold the peerless city, lifting high

But whence his exil'd feet so soon must part, Its hundred spires and edgʻd with bristling masts, Leaving no trace behind. In whose strong breast beat half a million hearts Instinct with hurrying life. The grey-hair'd man

Still, lingering flowers, Remembereth well, how the dank waters crept

The resonance of summer, cheer the nooks, Where now, in qneenly pomp, her court she holds. Where the sun longest smiles. Thou fairest Isle Next, gleams the Isle, where lengthen'd line of Of all my feet hath trodden,-purest gem coast

Amid the sparkling waters of the bay,– Is lov'd by Ceres, and where varying swells

I grieve to say farewell. And for the sake The rural landscape. On its western height

Of those I love, and for the inemories sweet, A noble city lowers, and 'neath its wing

And sacred hospitalities, that cling One, whose pore domes are wrapp'd in hallow'd Around the mansion whence my steps depart,shades,

Peace be within thy palace homes,--that crest Silent, yet populous, and throngh whose gates

Each sea girt hill, and 'neath the humblest roofs Press on the unreturning denizens.

That nestle 'mid thy dells : and when I dream Oh Greenwood! loveliest spot for last repose,

Of some blest Eden that surviv'd the fall, When the worn pilgrimage of life is o'er,

That dream shall be of thee, Even thy dim outline, through the haze, is dear.

Onward, by Coney Island's silvery reef

The Indian name for Staten Island was Monacnong, or To where between its lowly valves of sand

Enchanted Woods, signifying admiration of its delightful Opes the highway of nations. Through it, pours' forest scenery.

NATIONAL OBSERVATORY. cause. The disturbance was far beyond the reach of

the unaided eye; and was unknown to telescopic visAddressed to the Hon. John Quincy Adams.

jon. But there were Astronomers living who, for the WASHINGTON, Nov. 171h, 1847.

first time, underlook to invest mathematical analysis Dear Sir,—You did me the honor yesterday to with the space-penetrating power of the telescope. ask that I would give a written description of the They succeeded in the bold attempt, and from the Observatory, with other information relating there- closet pointed the observer's telescope to the locus to, including an explanation of the object and uses of the stranger. The circumstances connected of the different instruments.

with the discovery of the planet Neptune are alone I need not speak of the pleasure it gives me to sufficient to starnp the age in which we live, as a comply with your request; the only alloy to this remarkable era in the progress of Astronomy. So pleasure is found in the circumstance that I have too with regard to Struve's “ Stellar Astronomy" not the leisure, and if the leisure, not the ability to and Mädler's “Central Sun."* This object or point, make the answer as full or as satisfactory as I invisible though it be, and incorporeal though it would have it.

may be, has been made to “tremble on the verge Your efforts to advance in America the cause of of analysis." These illustrious savans, with a depractical Astronomy, are known to the world. The gree of probability and a force of reasoning, that lively interest which you continue to manifest in all have every where arrested the attention of Astronthat concerns the Observatory, causes you to be omers and challenged the respect of Mathematicians, considered as one of its most active and zealous have shown that the sun, moon and planets, with friends. It is proud of the relation. It feels hon- their train of satellites and comets, are in motion ored, and is encouraged by every additional proof as a unit, if I may be allowed the figure, about of the interest felt by you in its pursuits and for some grand centre poised in the remote regions of its prosperity.

space; and situated in the direction of the Pliades As a subject for congratulation with one who towards the star Aleyone. Perhaps this point is has borne so conspicious a part in establishing a also the “ Central Sun" about which the suns of a Naval and National Observatory in this country, thousand other systems hold their way.

Our lupermit me to call your attention to the interest, minary, with its splendid retinue, is computed to which, since the establishment by the government revolve about this centre at a rate of not less of such an Institution, has commenced to manisest than thirty millions of miles in a year; yet so reitself in the public mind in the cause of practical mote is it that many millions of our years are reAstronomy.

quired for the completion of one revolution. Here The Act of Congress founding this establish- then, indeed, is an “annus magnus" of vast import. ment, was passed in 1842. Since that time pub- In the conlemplation of it, may we not regard those lic meetings have been held, plans matured, and comes which dash through our system, never to subscriptions proposed in various parts of the coun- return, as lights sent from other systems to guide try for establishing Observatories. It is not haz- us on our way? Or at least may we not feel assured arding loo much to say that within the last five or that they answer wise and useful parpuses in the six years, more has been done in the United States great economy? to encourage and advance Astronomical science, I might point to other triumphs of mind over and that more has been added to the general stock matter, in illustration of the length of line which of such knowledge, than during the whole period Astronomers and Mathematicians are casting out, of our previous existence, either as a nation or a to fathom and explore the regions of space. people ; and in this fact, the friends of the science Pingre's comet is just now about to make its apdo but recognize the first fruits of the seeds that pearance for the third recorded time, to the inhabi. were cast by you many years ago.

tants of the earth. On the occasion of each of its There never has been, in the history of Astrop- former visits, it carried terror and dismay to the omy, a period of so much activity and energy as minds of Kings and Princes. In 1264, it was rethe present.

Within the last two years, the names garded as a messenger charged with the execution of four new members have been added to the list of sentence of death upon Pope Urban IV. of planets.* Within this time the world has been At its next return, the Emperor Charles V. of astonished, and the mightiest intellects in it have Spain, wrote of it, His ergo indiceis me mea fala considered with admiration the feals that have been vocant.It is said that he resigned his crown to performed by men engaged in Astronomical pur- prepare for the dread summons. suits. The most remote planet known to the sys- It has now been gone for another period of near tem, was subject to perturbations from an unknown three hundred years, and is soon to come back pro

Since this was written another planet has been discov. * Sir John Herschel's Cape Observations is annther of ered. Flora is its name, and it is the 8th in the family of those great works which mark the progress of, and slamp Astroids.

the spirit of the age upon, Astronomical pursuits.

vided with an "arming" which will be as significantl 4th. The Prime Vertical Transit Instrument, to the Astronomer of what it has encountered in Pistor & Martins, Berlin. Observers, W. A. the depths of space, as is of the depths of the Wayne, Lient. U. S. N., and James Johnson Pitocean, the sand to the mariner which adheres to his tigrew, a young Mathematician from N. Carolina. lead.

5th. The Equatorial, Murz & Mahler, Munich. But so far from its expected appearance, in 1848, Occasional Observers, myself and Joseph S. Hubbeing cause of dread and alarm to Powers and bard, Professor of Mathematics, V. S. N. Poientales, its coming is looked for even by the mul- 6th. The great “Refraction Circle,” Ertel & titude, with a degree of eager interest and will be Son, Munich. Observers, none. hailed with pleasure and delight in many lands. Lieut. Page is in daily expectation of orders to

From a mysterious messenger, bringing tidings sea, and Lieut. Steedman has been in training to of a dreadful, potent and awful calamity to a terror- take his place at the Mural. Hence the names of stricken world, Astronomy by its progress has three officers for that Instrument. Professor Hubchanged in the minds of men the character of bard has been recently detailed for duty not concomels; they have been made obedient to law, sub- nected with the Observatory. When he returns, servient, instructive and useful 10 man, in his ap- he will observe regularly with the Equatorial. ward and onward progress. They teach important As soon as practicable I propose also to place traths, and assist to reveal the secrets of nature. professor Keith at the Refraction Circle.

You, yourself, may recollect the time when As- It is a rule among Astronomers to consider an tronomers were called upon to quiet the public mind additional assistant at an Observatory which has as in one of the most refined capitals of Europe, and many as two observers already employed, to be soothe the dreadful apprehensions with which the worth more than two better men at a new Obserapproach of a comet was regarded. Yet even du- vatory. ring the short interval, such has been the activity Considering that the expense of buildings, piers and the progress in this department of science, that and instruments has already been incurred for this comels have ceased to be regarded as objects of Observatory,—it is obviously more in conformity terror sent, at long intervals, to warn or to punish ; with the principles of true economy to apply force they are rather looked upon as fellow-travellers and enough to give the instruments full occupation instructive companions to man in his journies whenever the weather will admit, than to have through space.

them only half manned, or feebly served. Instead of years, scarcely a month now elapses Accordingly I have constantly aimed to have at without the announcement that some new comel least two observers for each instrument; so that has been discovered; such is the activity of re. when the night is clear there may always be an eye search. The people of America have caught up for every Telescope in the Observatory. the spirit, and are beginning actively to engage in But the unusual demand for officers afloat on the Astronomical pursuits.* You have had the subject, one hand and their anxiety for war service on the as far as this country is concerned, anxiously at other, have made it difficult, during the last year, heart for years : wherefore I consider the present 10 keep at the Observatory its full compliment of occasion as one for congratulation. Pardon, there observers. fore, the digression.

The West Transit instrument is mounted on the The Astronomical Instruments of the Observa. Meridian in the West wing of the Observatory. tory, with Telescopes allached, are six. The reg. It has an object glass of 5.4 inches aperture, with a olar Observers, eight.

focal length of 7 feel I inch. A clock is an indispen1st. The West Transit Instrument, made by sable companion of this instrument, as a time-keeper Ertel & Son, of Munich. Observers, Mark H. of some sort is of every Astronomical Telescope. Beecher and Ruel Keith, Professors of Mathema- The clock is a mercurial pendulum, by Parkinson tics, U. S. N.

and Frodsham. 2nd. The Mural Circle, made by Tonghton & The Transit instrument affords data for the de. Simms, London. Observers, Thomas J. Page and termination of Right Ascensions. By it time Charles Steedman, Lieutenants, and J. H.C. Cof- is determined-clocks rated, etc. fin, Professor of Mathematics, U. S. N.

The Mural Circle, with the Meridian Circle, is 3rd. The Meridian Circle, Ertel & Son. Ob- mounted in the East wing. It is 5 feet in diameservers, William T. Muse, Lieutenant, and James ter and has a Telescope with an object glass of 4.1 Major, Professor of Mathematics, U. S. N. inches aperture, and 5 feet focus. The Mural Cir

cle is for the determination of Declinations. By

it Latitude is also determined. • The last Comet was first discovered by a lady of your The Meridian Circle has a Microscope Bearer own State-(Miss Mitchell of Namucket.) She has also compoted its orbit. Thus Maria Mitchell's Comet is ano

with 4 Microscopes; and 2 circles of 30 inches dither evidence of the attention wbich the subject of Astron. ameter, one for degrees and minutes, and the other omy is exciting in this country.

for seconds, connected with a telescope of 3.8 inches aperture, and 4 feet 11 inches focal length. Clock, | serving only as the object to be observed crosses mercurial pendulum, Charles Frodsham. This such great circle, which, with the first three named, clock answers also for the Mural.

is the Meridian, and with the 4th and 6th the Prime This instrument unites the transit instrument Vertical. and the Mural Circle. It is for the determination The object of the Equatorial is to observe ocof both co-ordinates.

cultations and eclipses, to determine the places of The Prime Vertical Transit Instrument, is moun- comets and planets by differential measurements. ted on the Prime Vertical in the first apartment of It is also used for measuring the angular disthe South wing. It has no circle except a finder. tance and position between double stars, for meaThe telescope has a focal length of 6 feet and suring the diameters of planets, etc. It may be 4.8 inches aperture. Clock, grid-iron pendulum, turned for observations at any time upon any object Charles Frodsham.

in whatever part of the visible heavens. Its greater This instrument is also for the determination of optical and space-penetrating powers, invest its laRight Ascensions and Declinations. But while it is bors in physical Astronomy with exceeding intercapable of a higher degree of accuracy than any est and give it other advantages, which are not one of the aforementioned instruments, it is confin- possessed by its more humble companions below, ed to a more narrow field; it works more slowly; though for differential position it is subsidiary to and cannot compete with its compeers in number and dependent upon their determinations. or subjects of observation. They can observe all The Refraction Circle has two Microscope Bearobjects that appear above the horizon and cross the ers, which carry six microscopes each ; iwo gradmeridian-it, those only which cross its prime ver- uated circles of four feet each, with divisions for tical—which in this instance embraces those stars every 2' of arc on gold; and a Telescope of 5.8 inwhose parallels of Declination are included between ches clear aperture and eight and a half feet focal the Equator and the Zenith of this Observatory. length. This instrument is new in its combinations

The Declinations determined with this instru- and construction. It unites the exquisite accuracy ment are surprisingly accurate. It is capable of of the Prime Vertical Transit instrument, with all affording results possessed of a higher degree of the advantages, compass, and capabilities of the accuracy perhaps than those oblained from any Mural Circle and Zenith Sector. It is the first of other instrument at present known to Astronomy. its kind ever made, and was constructed from plans This is in part owing to physical and mathematical and drawings prepared at this Observatory. The advantages derived from its position in the prime makers pronounce it to be the most complete asvertical, and partly to mechanical and instrumental tronomical instrument that has ever left their hands. peculiarities. It is a new instrument; It was in. Its performance, however, remains to be tried. vented by the direction of the Central Observatory Equally adapted for mounting on the Meridian of Russia, and this is the only other instrument of or the Prime Vertical, it surpasses all the first four the kind except his.

mentioned instruments for power and compass : Its position frees its results from and makes them and in means for imparting accuracy to results, it independent of the effects and uncertainties of at- possesses advantages which none of them have. mospherical refraction, and of the numerous im- It is situated in the second apartment of the perfections and sources of error to which instro - South wing, which has been extended to receive ments with graduated arcs and circles are liable. it. It is, at present, mounted on the Prime VertiIls peculiar construction and extraordinary facili- cal, but its ultimate destination is the Meridian. ties of reversal, neutralize other instrumental im- It is the only Astronomical instrument which perfections which are, also, fruitful sources of error has ever been constructed and mounted, that indewhenever their effects remain for the skill and pa- pendent of any previous hypothesis is capable of tience of the observer to detect and expose. It is determining directly and immediately the effect of particularly well adapted for investigating the pro- atmospherical refractions in optically displacing blem of Stellar Parallax.

the heavenly bodies. It is the first instrument The equatorial has an object glass of 9.6 inches ever used on this continent for the investigation aperture and fourteen and a half feet focal length of this most important problem ; it will begin these It is provided with clock work for siderial motion, investigations on the Prime Vertical and end and the observations are timed from a siderial chro- them on the Meridian. Hence it is called the nometer rated by the clocks below. It rests in the Refraction Circle, though there are many other dome, and surmounts a massive block of granite subjects and problems towards the affording of which is supported by a conical pier of brick work, data for the solution or investigation of which it is rising from the foundation of the building and pass- equally well adapted. ing up in isolation of the floors and all other parts Theory points to perturbations by the moon and of the Observatory.

planets upon the earth's centre of gravity. These Each one of the other instruments moves in the daily disturbances, except as their effects are ex. plane of but one great circle, and is capable of ob-'hibited by the tides of the ocean, or marked by the

Barometer, have never, that I am aware of, been on the side opposite the first. Thus the maximum made the subject of direct observation. deviation will be multiplied four times, and so mul

This instrument, therefore, suggests a class of tiplied, will be brought under the highest magnifying observations entirely new. And it is proposed to powers of the instrument for detection and obserundertake them; for, whether successful or not, vation. the experiment will not be needless ; but in either The facility with which the instrument is reevent will be possessed of both interest and value. versed and the manner in which it is supported on

In consequence of the influence of the moon and its pier, will impart to its results, a degree of conother bodies, the centre of attraction of the earth fidence as to accuracy of determination that but may be supposed to revolve about its geometrical few instruments have ever afforded. centre. It may be that this instrument is capable But it would be altogether out of place and preof determining, by actual observation, the orbit mature to discuss its powers here, or to anticipate which one of these centres makes about the other; results. I, therefore, pass on to the other subjects for, by an optical artifice, the centre of attraction, upon which you desire information. so to speak, or, which is the same thing, (the nadir According to the British Association for the point, which is in a line with this centre,) may be advancement of science, the vast sums of money rendered visible ; it only remains to be seen whether which have been spent by Astronomers in doing this instrument have powers sufficient to detect its over again what has been better done elsewhere, minute changes. Permit me to explain- in determining Astronomical data, might have al

By turning the Telescope down upon a basin of most created new sciences of observation. of mercury, the image of the spider-thread, which Not to make this Observatory liable to such a is placed in the stellar focus of the object glass charge, a plan has been adopted for its labors which, of the Telescope, may be seen as thoagh it were while the plan seeks to avoid doing over again an object at an infinite distance. Resorting to this what has already been well done, aims at results optical artifice, by which the most attenuated line both useful to the world and creditable to the counis placed in the nadir and directly in a line with try. The general outlines of this plan are to keep the centre of gravitation, and taking advantage of up a regular and systematic series of observations the peculiar and extraordinary collimating powers upon the sun, moon and planets and certain fundaof this instrument, it will be impossible for any mental stars, with the view of procuring data for deviation of the plummet amounting on the surface the American Nautical Almanac. But the Obserof the earth to as much as the breadth of the finest vers and instruments are capable of many more gossamer, from its normal state, to escape obser- observations than these; and with the views of fully vation. Permit me to illustrate by an example : occupying the time of each, I, at an early day,

Suppose the moon to be on the meridian at proposed regularly and systematically to penetrate, its lower culmination, and that the spider line with our excellent Telescope, every point of space in the the focus of the Telescope be made to oc- in the visible heavens, with the view of assigning cult its own image over a basin of mercury and as position and magnitude, and of cataloguing every seen in the nadir, we shall then have the most per- star, cluster, nebulae or object that should pass fect plummet that can be dropped. The position of through the field of view. the Telescope is then noted, and in this position Leave was sought and readily granted to carry it remains. Suppose now after the moon rises, this plan into effect, and the labor of near two and reaches that altitude in the East at which her years has already been expended upon it. A catdisturbance of the plummet is a maximum, that alogue of about 1,200 stars, most of thein unknown the Telescope is again examined and the spider- to existing catalogues, is the result of the first thread and its image found to be no longer in occul- year's work in this field. tation. This, assuming stability in all other re- The plan originally contemplated and designed spects to be perfect, will be owing lo the fact, that is to sweep over the same belt twice, but not on the centre of attraction has changed its position, the same night, nor with the same instrument or and passed, also, to the East of the geometrical observer. Supposing the conditions of atmosphere, centre, so to speak, of the earth, and, in conse-instrument and eye to be the same, all the stars, quence, the mercury in the basin has adapted it. and no more, which are observed during the first self to this new centre, and, therefore, changed sweep, should be observed during the second. The its inclination, by an amount equal to the deflec- work in this case is complete. tion that would be produced upon the plummet. But suppose, and this is generally the case, that The maximum effect of this change, being seen by stars are observed in one sweep which are not obreflection, is apparently doubled.

served in the other, the Equatorial is then turned When the moon reaches a like altitude West, upon the same belt to 'reconcile discrepancies; so the same takes place. But, in this instance, the that no star may be entered in the catalogue withimage appears to the West, instead of the East of out having been made the subject of observation the real thread, and the effect is again doubled, but'at least twice, and each time on a different occa

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