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of the final result; and better still, if this test bejbe reported to the Observatory, these sources of more rigorously applied by the transit instrument error may be eliminated. It will be a part of the whenever it is practicable. In addition to this, the daily business at the Observatory to observe the observation of the meridian passages of the moon's moon's place; and when its actual place upon any bright limb and of the stars near its path ought to day is compared with that given by the tables, the be made as frequently as possible while at a port, error in the latter becomes apparent, and may be the longitude of which has never been ascertained applied to the results of any calculation at sea, in by more correct methods. A mass of data would which the same tables were employed. It would thus be collected for the correction of our charts, be also the duty of the persons having charge of which would soon render these sufficiently accu- the Observatory to possess themselves of the rerate for the general purposes of navigation. But sults of the latest and best observations made by that the greatest advantage may be derived from the vessels of other countries and by scientific this system of observation, the original observa- travellers, and to embody in our charts such as tions themselves with every accompanying circum- might be deemed worthy of credit. stance ought to be deposited at the Observatory, The survey of our own coast, which is so extenthat their relative importance may be judged of, sive and in some places so dangerous to approach, and the most valuable of them reduced and calcu- is certainly one of the most important works underlated. Their reduction on ship board, at the time taken by the government. But as it has been conthey are made, cannot be effected with sufficient nected with another department of the public seraccuracy, because, in the first place, the methods vice, it does not come properly within the scope of used for this purpose, as they are generally de- my present remarks; and yet the Observatory may veloped in treatises on Navigation, are designed to be made to sustain a relation to that work which I give results only approximately true.

will not pass by without a brief allusion. Take, for example, the very convenient method of Mr. Hassler stated to the committee, appointed working a “ Lunar Distance" given by Dr. Bow- by the last Congress, on the Coast Surrey, as the ditch in the first edition of his “Practical Navi- reason why charts, of those parts of the coast gator," and which he has farther improved by ad- which had been surveyed, had not been published, ditional tables in the last edition of that extremely that the geographical position of no point in the valuable work. The distance obtained, according United States had been sufficiently well determined to that method, is defective by reason of neglecting to deduce therefrom the latitudes and longitudes of several small corrections due, 1st. to the variations the several stations comprised in the primary trianin the refractive power of the atmosphere ; 2nd, to gulation. I was the more surprised at this because the spheroidal figure of the earth ; 3rd, to the hori. his triangulation lies in the vicinity of sereral zontal parallax of the moon when different from cities and towns which I believe lay claim to the 57 minutes and 30 seconds. It is not thought ne possession of Observatories of a grade at least sufcessary to introduce any such refinements into nau- ficient to determine with a considerable degree of tical calculations, as the observations upon which approximation their coördinates of position. It they are founded are generally made under circum- must be borne in mind, that after the geodetical disstances but little favorable to a high degree of tances between the several stations have been calaccuracy. But when peculiarly favorable circum- culated, the latitude and longitude of at least 028 stances are seized upon for making them, as may of the stations and the azimuth of one of the sides be done occasionally on deck and always on shore, must be determined, in order to assign latitudes the results should be obtained by more accurate and longitudes to the other stations. But in a surmethods, especially when they are to serve for the vey so extensive as that of the United States" correction of charts. I speak from experience coast, the latitude and longitude of but one station when I say, that with a well-constructed Reflecting will not suffice. To give to the method, adopted Circle, and in a favorable position of the moon in for the survey, all of the accuracy of which it is respect to a star, their apparent distance may be susceptible, the figure of that portion of the earth measured with an accuracy which will warrant the over which the triangulation is spread, must be dereduction of the observation by a process more duced. To do this, the triangulation must not only perfect than those usually employed at sea. But be conducted with all the precision of modern in the second place, if the methods used at sea science and art, and be verified by the measure were not defective in the particulars above stated, ment of several bases, but temporary Observatoyet the tabular distance of the moon from the starries must be erected at certain stations along the is regarded as perfectly accurate, while in point of series of triangles, and the geographical position fact it is inaccurate by the whole amount of error of such stations independently obtained by the best in the Lunar Tables. In like manner the calcula- methods and with the utmost care. In the first tion of the longitude of a place founded upon Lunar elimination of the errors in the latitudes and longiculminations is affected by the errors of ihe Lunar tudes of the stations as deduced by calculation, the Tables. But when the original observations shall Observatory, if it be made one of the stations la

the survey.

the primitive triangulation, will afford very essen-| ralty” of Great Britain, or the “ Bureau des Lontial service. Its instrumental resources will be gitudes" of France, for the means of navigating the such, it is to be presumed, as will admit of the last high seas with safely. And is it not discreditable degree of accuracy in the determination of its posi- to the science and enterprise of our country that it tion. And as such, it may, and doubtless will be, should be so ? There is not an original Ephemeris one of the most important fundamental points in published in America. Blunt's, of New York,

which is so much used by our commercial vessels, If this degree of precision be not given to the is merely a reprint of the most useful parts of the Coast Survey, it will loose its scientific character, British Nautical Almanac; and this epitome, or and very imperfectly fulfil the end it is intended to some other, or the British Almanac itself, or the accomplish. If its results are not founded upon “ Connaissance des Temps,” will be found on board the determination of the special configuration of of all our vessels of war. This service to our the surface over which it extends, I would not be commerce and Navy may be performed at Washdisposed to place as much confidence in them, as I ington as well as at Greenwich, or Paris, and would in latitudes independently determined by not only the interest, but the honor of the counTroughton's Zenith Sector and longitudes by sig- try requires that it should be done. nals of fire.

But furthermore, the Observatory may be orI will dismiss this subject, unexpectedly alluded ganized upon such a scale as to enable it w con to at all, with but one other remark. That the ori- tribute its share to the advancement of Astronomy, ginal observations, with all the attendant circum- which is the oldest of the sciences, which, perstances, ought to be reported without an erasure, haps, has, more than any other, contributed to the without the suppression even of those known at progress of civilization and refinement throughout the time to be defective. The observer onght not the world, and which must depend for its successhimself to be at liberty to reject any instrumental ful prosecution, so far as instrumental results are result, however discordant it may seem to be with concerned, upon the countenance and munificence those formerly obtained. He may state his rea- of governments. And it is gratifying to see to sons why he has not confidence in any particular what extent this noble science has been fostered observation, but should not have authority to ex- by the civil powers of Europe. There are not clude it from the result. It is only in this way less than forty public Observatories, established in that a correct judgment can be formed of the pro- Europe and its colonies, of which the most celehable instrumental and personal errors which are brated and useful are those at Greenwich, Dublin, inseparable, to some extent, from observations of Cape of Good Hope, Paramatta, Paris, Torin, this sort. The observations ought to be committed Altona, Bremen, Königsburg, Berlin, Gotha, Göt10 a separate commission, or bureau, by which the tingen and Dorpat. calculations and reductions should be made with But while the governments of Europe have the utmost exactness. I am aware, that from mo- seemed to vie with each other in the number and tives of economy those who make observations in character of their public Observatories, there is the summer, calculate the results during the suc- not one, so far as I know, in this country which ceeding winter ;-but it is worth while to inquire deserves to be ranked among them. It surely must whether observations cannot be pushed forward in be a narrow and prejudiced mind, that would arthe South during winter, so as to expedite the rest the progress of a science because every step progress of the work to a very considerable extent. of it has not a palpable and immediate relation to And if it is contemplated, as I hear, to carry the the ordinary business of life. We cannot always primary triangulation as far into the interior as the foresee in what manner precisely our more abstract mountains, unless the work be pushed forward more and refined speculations will bear upon

the common energetically, our children's children will not live interests of mankind; and yet assuredly, if we are to see the benefits resulting from its completion ; in the pursuit of Truth, its attainment will prove and, in the meanwhile, the loss of life and pro- highly useful to the improvement and happiness of perty may greatly exceed the additional expense our species. Our present subject furnishes an apt which its more vigorous prosecution will require. illustration of the propriety of this remark. With

The objects already noticed, as they bear a most out the high speculations of Geometers upon ceobvious and immediate relation to the interests of lestial mechanics, the method of Lunar Distances, the Navy, were probably the only ones had in con- so valuable at sea for determining longitudes, templation in the establishment of the Observatory. could never have been realized. The possibility But there are others no less important which may of applying the method depends upon the accube accomplished by a very trifling addition to the racy of the Lunar Tables; and these never could appropriations which will be necessary for the have attained their present degree of perfection, former.

without the labors, purely geometrical, to which I Our Navy has always been and is yet dependent have referred. Indeed, Astronomy is one conupon the “Lords Commissioners of the Admi-'tinued illustration of the truth of the remark, that

the satisfaction of our commonest wants frequently In Stellar Astronomy our knowledge is still more demands scientific speculations of a character the imperfect. We do not as yet know the distances most sublime. Whether we consider the perfec- of the fixed stars from us, which is the simplest tion of its scientific character, the generality of element that can enter into our researches conits laws, or the importance of its results, Astrono- cerning them; unless, indeed, 61st Cygni be an my must confessedly stand the first of the natural exception, to which Bessel thinks his observations sciences. It furnishes us with all our measures of assign an annual parallax of 0. 3136 of a second. time—with all our knowledge in respect to the It must still, however, be admitted to be doublful figure and dimensions of the planet which we in- whether this, or any other star has an appreciable habit—with the means of determining positions parallax. The accurate observation of binary stars upon its surface, and of directing our course along is likely to prove the most fertile source of discoits pathless waters—and with our best and only very in respect to these distant bodies. It already invariable units of linear measure. Surely it be- seems to be quite probable, that their dynaminal comes the United States, as a great commercial and relations to each other, may be adequately exnavigating nation, to extend a fostering care to a plained upon the hypothesis, that they circulate department of human knowledge which is so iden- about their common centre of gravity, by virtue of tified with its interests and honor.

a force identical in its laws with gravitation. I And though Astronomy has, in many points of think farther observation necessary to warrant this view, attained a degree of perfection to which no extraordinary extension of gravitation, although other science can lay claim, yet it must not be the analogical argument in favor of it is very strong. supposed that the establishment of an Observatory In such delicate observations, is it yet certain of proper rank can contribute nothing to its future whether the one star describes an elliptic orbit progress.

about the other placed at the focus or the centre, In respect to our solar system there are several or at any intermediate point ? As long as doubt interesting and delicate questions which are yet to exists in regard to the relative position of the latter, be solved.

we should not be hasty in drawing our conclusions More accurate observation will show whether in respect to the law of attraction subsisting besomething is still wanting to the solar theory, as is tween the bodies. I regret that I have not seen suspected by Bessel and Airy.

the most recent papers upon this interesting subThe planets are yet to be more nicely weighed, ject by Sir J. F. Herschell. They are said to be and the tables of their motions more perfectly con- replete with valuable information, and I regret yet structed.

more that I have not as yet been able to obtain bis Astronomers already feel the absolute necessity method communicated to the Astronomical Soof investigating more minutely the refraction which ciety, for the calculation and construction of the rays of light undergo in traversing the atmosphere, elements of the orbits of binary stars, which deand of applying with greater accuracy the correc- pends exclusively upon the observed angles of tions due to variations in temperature, density and position. humidity. The errors which exist in our best ta- From the difference of the observed times which bles of refraction, are unfortunately involved in the revolving star requires to describe the two pormany of our most important and delicate re- tions of its orbit symmetrical to the Axis Major, searches, such as the determination of the Obli- Savary has proposed to determine its distance from quity of the Ecliptic, the place of the equinox, the earth. The idea is ingenious, but it remains the positions of the stars and many others. The for future observations to establish its practicability. constants of nutation and aberration are still in In this hasty sketch of the objects to be accomdoubt to a small extent ; and, in a word, there is plished by the establishment of an Observatory, I no instrumental result employed in Astronomy, must not forget that magnetism is to receive the which may not undergo a modification, greater or special attention of those who have the charge of less, when better instruments shall be constructed it

. And I perceive that a separate building has and improved methods of observation employed. very properly been erected for this purpose, and

Cometary Astronomy is yet in its infancy. We that it is the intention of the governmeni to supply have determined, with tolerable precision, the or- it with the best instruments. bits of only three or four of the many hundreds To a maritime nation the subject of Magnetism which belong to our system. In respect to their is one of much importance. All Marine Charts physical constitution, we may be said to be pro- must show the variation of the Magnetic from the foundly ignorant. But though we know so little of true meridian, at least approximately, in every them, yet important results have already flowed sea and place visited by our commercial and naval from the attention which astronomers have paid to vessels. The needle is essential to direct the resthese mysterious bodies. By means of them we sel upon any designated course, and therefore the have arrived at the interesting fact of the exis. laws by which its indications are controlled should tence of a resisting medium.

be carefully investigated. There is but little doubt that the Magnetic forces of the earth are subjec- Having consumed so much of the space allotted ted to laws which may be discovered, and from to this letter, in treating of the objects to be acwhich, if they were known, the courses and varia- complished by the establishment of an Observatory, tions of the isoclinal and isodynamic lines might I must be very brief on the subject of its organibe deduced by calculation. We feel in this depart- zation. ment of science as if the conception of some great It should of course be put under the direction of and fundamental truth was just about to burst upon one having every qualification to conduct the busius, not unlike that which opened up before the ness of it in the best manner possible. It should vision of the philosopher of Samos when he utter- be furnished with Astronomical and Magnetical ined the rapturous “s’ionka.” But already is theory struments, as powerful and as perfect as art can in advance of observation, particularly observation render them. The number of assistants should be of that continued and delicate character, which sufficient to keep up a continued series of observaalone can conduct to definite and certain results. tions in the Magnetic Observatory, and also in the

Europe has recently taken up this subject with Astronomical, when the weather permits. becoming interest and zeal. The methods of ob- All of the observations with every accompanyservation devised and practised in Germany have ing circumstance should be published; and the extended to other countries. Magnetical Observa- same properly reduced. It is not enough that obtories have been established in various quarters of servations be skilfully made; they should be rethe globe, as at St. Helena, the Cape of Good duced in the most rigid and exact manner. It is Hope, Van Dieman's Land, Canada, India, &c., in the least part of an Astronomer's business to make which observations are prosecuted, strictly in con- an observation. The results are to be exhibited cert with the Observatories in Europe. It is there and compared with theory, and here all his talents fore with pride and pleasure that I hail the estab- and mental resources find the fullest scope. lishment of such an Observatory in the City of Many of the observations of Bradley and MaskWashington, which may be made to play an im- alyne remain to this day almost useless for the portant part in that grand system of concerted ob- want of reduction, and England ingloriously sufservation which has been undertaken by the princi- fered the Astronomers of the continent to profit pal nations of the earth; and every American chiefly by the instrumental results of her most acmust desire to see it organized and conducted in a complished observers, by neglecting this very esmanner worthy of science and of our country. It sential part of the work of an Observatory. must not be forgotten that a Magnetical Observa- As to the actual expense of establishing and tory is essential to give value to the individual con- conducting an Observatory on the scale contemplatributions which the scientific men of our country ted in the foregoing remarks, the estimate made by are continually making to our stock of Magnetical Mr. Adams, in his “ Report on the Smithsonian Beinformation. The differential dip, variation and quest," seems to be founded on satisfactory data, intensity are more readily and accurately found and to that I beg leave to refer you. than the absolute; and therefore the Observatory That estimate did not include a Magnetic Obat Washington will be a fundamental point of com- servatory, which will require an additional obserparison for all observations made by individual en ver, and probably two. It should be recollected terprise.

that the expense for buildings and instruments has The instruments used in Magnetic Surveys, whe- already been incurred, and that provision only has ther on land or sea, ought to be examined at the to be made for the annual operations of the estabObservatory both before and after their use, and lishment. The whole annual cost would not exthis should be a service required of the Observa- ceed $15,000. And if the buildings and instrutory, independently of the observations proper to ments are, as Lieut. Gilliss reports, of the first itself.

class, it is worthy the consideration of the GovernAnd while on ship board observations cannot be ment, whether the additional expense required to made with that accuracy which will render them organize the Observatory in a manner to fulfil all valuable in the discussion of theoretical views; the important ends which such an establishment yet they will be highly useful for the correction of may subserve, would not be fully justified. the Magnetic Charts now in common use. It would With sentiments of the highest regard, therefore be desirable to furnish each vessel of the

I am your obedient servant, Navy with the best means of making them.


guage of indictments as a "false, scandalous and EDITOR'S TABLE.

malicious libel." Let us take a few examples.

At p. 26 Mr. R.'s change of political position is SAWYER'S LIFE OF RANDOLPH. said to have grown out of a certain presidential “The Lion was dead that received the kick."

Inessage of January 17, 1806. Now there was No man ever lived whose biography was more is there spoken of.

neither then, nor at any time, any such message as likely to excite a general interest and to be well

At p. 47 there is a most indecent anecdote, in received by the public than Randolph of Roanoke. telling which Mr. S. affects accuracy, and corrects The profound silence of the press on that subject some other writer. Here he introduces a female is a curious fact. It is understood that considera- name. It is well for him, that, as no such thing tions of delicacy may have restrained his near rela- ever happened, there was no such lady as he speaks tions pending the controversy arising out of his of. If there were, and she had a relation in the will. The question of his sanity is one on which world with the spirit of a man, Mr. S. would be it would have been wrong to preoccupy the public most deservedly punished. mind; and no biographer could, in justice to him, At p. 41 Mr. R. is represented as courting popuhave been silent on that subject. His other near lar favor after his defeat in 1813, by Mr. Eppes, friends may be supposed to have been restrained by and the arts used by him are detailed. Every man, the same consideration.

woman and child in Mr. R.'s district knows that But why was not his life written by others ? his demeanor was never so high and haughty as at Lord Byron was hardly dead before the Dallas's that time; that there was no such partizan as is and Leigh Hunts, &c., &c., were seeking to make there mentioned ; that his deportment toward all a profit of the little intercourse with him which he to whom the description could apply was absolutely had unadvisedly permitted. Why did nothing of repulsive; and that the disgusting hypocrisy of the sort happen in this case ? The answer is to be frequenting Baptist meeting houses to conciliate found in the delicacy which always has distin- that sect, and making a display of religious zeal guished Virginians. They felt that it was due to was never heard of there. Mr. R.'s friends to decide whether the veil should

We instance these things as not resting on pribe drawn aside from his private life. Of the hun-vate knowledge, but on notoriety. They manifest dreds, therefore, who might have made entertain- a reckless disregard of truth, which makes it supering books of reminiscences from the conversations Auous to contradict calumnies, the refutation of of a man whose words were, by turns, prophecy, which must depend on testimony of a more precise poetry and epigram, not one has published a line. and personal character. A Mr. Jacob Harvey, an Irishman, entertained the

Mr. S.'s disregard to truth is strikingly manipublic with such scraps as a short acquaintance fested in his neglect to inform himself of particoenabled him to collect. His account is probably lars which he might have learned from the most as faithful as he knew how to make it. But Mr. authentic sources. Mr. Randolph's brothers, Dr. H. had not the faculty to preserve the very words Brockenbrough and the Messrs. Leigh are known of Mr. R., and many of his anecdotes are, there- men, and Mr. S. could have reached either by fore, deficient in accuracy in this important point. letter. Had he done this, would he have called There was a tone in his style of conversation as Mr. R. the nephew of Edmund Randolph, and reprewell known to his friends as his voice, and, missing sented him as a member of his family, as at p. 10! that, they always know that the very words im- Would he have represented Mr. R.'s mother, at p. puted to him, were never spoken by him. With 9, as removing to Williamsburg with her husband, this exception, and that of a small volume of his when she was already dead? These are things of letters, nothing concerning him has ever, until now, small consequence in themselves. But to speak of been given to the public. In Virginia nothing at all. them without resorting to the means of knowledge

It remained for a citizen of another State, a at hand, shows an utter disregard to the first day stranger and an enemy, to interrupt, with his idle of an historian. gossip, this funereal silence, and to make a market What we have said, founded on no particular of his pretended knowledge of Mr. R. by vending knowledge, but on a notoriety so great, that each it at a distance from those who could have told his point we have touched on is probably known to bookseller that he knew nothing of his subject. 10,000 persons, as certainly as man can know that His means of knowledge are paraded on the title of which he was not an eye witness, is enough to page, where he announces that he was for sixteen satisfy the public that in purchasing the work in years the associate of Mr. R. in Congress.. But question, they may get gossip for their money, they he presently makes known that he was politically may get calumny, but they will certainly not get opposed to him; and all who know Mr. R. know an authentic biography of John Randolph. that to be so, at that time, was to be cut off from all intercourse with him. Hence, Mr. S. himself

The ORATION OF DEMOSTHENES ON THE CROWx; with tells no more of his own personal knowledge than

noles, by J. T. Champlin, Professor of Greek and Latin what passed at their first meeting. Giving him in Waterville College. Boston: James Monroe & Cum credit for intending to tell the truth, this fact may be taken, as he tells it, for what it is worth : and This volume ought to have received an earlier attention this is precisely as much as the public can safely It is just as good now as it was the day it came from the

from us. There is one comfort, however, in the matter. take on the authority of Mr. Sawyer. The rest press. There is nothing ephemeral about it

. It is not one of the work is made up of a very unskilful digest of that kind of works that must be praised the monit, or of the contents of the papers of the day, and a the year in which they come out, or be praised too late. collection of idle tales, of which not one' in ten The object of its preparation is excellent and carried out

with distinguished skill. We are much mistaken, if any has any foundation in truth. In many passages thing with ihe same design appear for a long time that can the work may be truly characterised in the lan-'in justice supplant it.

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