« PreviousContinue »
the more unmercifully apportioned, because all risk of opposition was removed; and they were treated the more contemptuously, in revenge of their unsuccessful and disastrous rebellion.
What permanent effect the recent revolution may have upon the condition of the Indians, cannot as yet be satisfactorily ascertained. Thus far, the tendency of it has been highly favorable to them, and there is every cause to believe it will continue so hereafter. The independence of a part of Peru is not yet sufficiently confirmed to have allowed the temporary governments, which have succeeded one another there, to do much for the internal improvement of the country; but in the districts formerly dependent on Buenos Ayres, something is already accomplished. The revolution has swept away at once the old distinctions, which the colonial system created and maintained. At the cry of liberty, the degraded casts rose simultaneously to vindicate their title to the rights of men and of freemen, all equally inspired with enthusiasm in the cause of independence, and admitted on equal terms to unite with the patriotic Spanish Americans in establishing a free representative government. The creoles are all natives of the country, in common with the Indians, and common tenants of the soil. It is their home. They do not come there across the ocean, for the purpose of realising a sudden fortune by rapacious exactions, and then returning to pour out their ill gotten gold into the lap of Spain. Their interest, on the contrary, is inseparably united to their native soil, and it will be their anxious endeavor to free South America from the infamy of its barbarous laws against the Indians; laws as fatal to the future prosperity of Peru, as they have been derogatory to the honor and humanity of its Spanish rulers.
ART. IV.-1. Fundamenta Astronomiæ pro anno MDCCLV, deducta ex observationibus viri incomparabilis James Bradley in Specula Astronomica Grenovicensi per annos 1750-1762 institutis. Auctore FRIDerico Wilhelmo BESSEL, Acad. Berol. Atque Petrop. Sodali, Instituti Gallici Corresp. Regiomonti, 1818. T. 1. pp. 328. 2. Tables Astronomiques publiées par le Bureau des Longitudes de France, viz.
Tables de La Lune. Par M. BURCKHARDT, Membre de l'Institut, etc. Paris. 1812.
Nouvelles Tables de Jupiter et de Saturne, calculées d'apres la théorie de M. Laplace, et suivant la division décimale de l'angle droit. Par M. BoUVARD. Paris. 1808.
Tables écliptiques des Satellites de Jupiter, d'apres la théorie de M. le Marquis de Laplace, et la totalité des Observations faites depuis 1662 jusqu'à l'an 1802. Par M. DELAMBRE. Paris. 1817.
3. Tables. By B. DE LINDENEAU, viz.
Tabula Veneris novæ et correcta, etc. Gothæ. 1810. Tabula Martis novæ et correctæ, etc. Eisenberg. 1811. Investigatio nova orbitæ a Mercurio circa solem descriptæ accedunt Tabula Planeta, etc. Gothæ. 1813.
4. Mémoire sur la figure de la Terre.
Par M. de LaPLACE, Mem. Acad. Sciences. Paris. 1817, 1818. THE science of Astronomy offers to our contemplation. some of the most powerful efforts of the human mind. pernicus, by the discovery of the motion of the planets about the sun; Kepler, by his elliptical theory, and the laws regulating the motions and distances of the planets, with the times of their periodical revolution; finally, Newton, by the discovery of the theory of gravity, opened the way for all the improvements, which have lately been made in this science. In the Principia, published in 1687, Newton pointed out the origin of the inequalities of the motions of the heavenly bodies, which had then been discovered by observation, and deduced others from the theory of gravity. No material alteration was made in his methods for more than half a century. Then began a new epoch in Astronomy, and the history of that science, for the last hundred years, will be forever memo
rable for the unexampled activity and great discoveries, which have been made. So important have been the labors of the practical astronomers, that a complete system of the planetary motions might be deduced from the observations made during this time; and if all the previous observations, even to the most remote antiquity, were lost, the effect on the tables of the sun, planets, and satellites, would hardly be perceived, since the great accuracy of modern observations more than compensates for the shortness of the interval. It is proposed in this article to give a short account of some of the most noted discoveries during this period, to take a slight view of the latest and most correct tables of the motions of the planets and satellites, and to make such remarks on the labors of astronomers and mathematicians, as may be necessary in the notices of the works proposed to be reviewed.
The career of modern improvement was begun by Dr Bradley, one of the most indefatigable astronomers of the last century. He was remarkable for his skill and accuracy, in tracing those minute changes in the places of the heavenly bodies, which had so much perplexed the astronomers who preceded him, and his labors were crowned with the most brilliant success, by the discovery of the Aberration of light and the Nutation of the earth's axis. His observations were so numerous, accurate, and important, that he may justly be placed in the same rank with Hipparchus and Tycho, the greatest and most accurate observers of ancient and modern times. He published an account of the aberration and nutation. His observations of the moon were also made public, and used by himself and others, in comparing and improving the lunar tables. A table of the places of 389 fixed stars was likewise deduced from his observations, and published by Dr Hornsby, but the great body of his observations, made at Greenwich while he was astronomer royal, were taken from the observatory by his executors, under the pretence that they were his private property, with the expectation of being paid for them by the government. A suit having been commenced for their recovery, the executors, in order to avoid it, presented them to Lord North, (so well known in the history of the American Revolution,) who gave them, in the year 1776, to the University of Oxford, of which he was Chancellor, upon the express condition, that they should immediately be
printed and published. But to the great disgrace of the University, and of Professor Hornsby, who had charge of the papers, they were withheld many years, notwithstanding the repeated solicitations and remonstrances of the Board of Longitude, who, in 1796, published several spirited resolutions, under the form of an appeal to the public, upon this very improper conduct. These observations were made between the years 1750 and 1762, but it was not till the year 1798 that the first volume was published, and the whole was not completed till the year 1805, almost half a century after the observations had been made; and during the whole of this time, while unexampled progress was making in all branches of astronomy, these invaluable observations, which would have facilitated very much the calculations of astronomers, were lying almost useless.
But it may well be questioned whether this delay will, on the whole, be any disadvantage to the future progress of astronomy. For if these observations of the stars had been published soon after Bradley's death, they could not then have been reduced so accurately, as at the present moment, because the precise values of the small reductions to be made to the observations for precession, nutation, aberration, and refraction, were not so well known, and it was not then usual to take such pains in computing and combining together many observations. Moreover, if the great labor of reducing the observations had been once gone through, even in a somewhat imperfect manner, it is probable that no one would have undertaken a new revision, as is the case with Flamsteed's observations. But, at the time of the publication of the observations, a considerable degree of interest had been excited, from the difficulties attending them, and this, with the well known accuracy of Bradley, was sufficient to procure an early and careful examination. Fortunately, at that time Bessel, the present astronomer royal at the observatory of Konigsberg, had just relinquished his mercantile pursuits, and with great success had devoted himself to astronomy. Having been furnished with a copy of Bradley's observations by Dr Olbers, he voluntarily undertook the task of reducing them, and no one was better qualified to do it, since he possessed, what is rarely united in the same individual, mathematical talents of the very first order, with great accuracy in
observations. The result of his labors is the important volume mentioned at the head of this article.
This work is divided into thirteen sections, in which Bessel successively treats of the various subjects connected with Bradley's observations, namely, the Instruments he used, and the corrections to be made to them. The Right Ascensions of his fundamental stars compared with the sun near the equiThe Latitude of Greenwich. The Refraction of the heavenly bodies, deduced solely from Bradley's observations, combining them together by an excellent theory, and with tables for the calculation, being more accurate than any tables of refraction, that had before been used by astronomers. The Obliquity of the Ecliptic from the observations of the solstices from 1753 to 1760. The Aberration of the fixed stars, with tables peculiarly adapted to the reduction of Bradley's observations, and an investigation of the quantity of the aberration, deduced from a great number of those observations, by which it would seem that the value of the aberration as found by Delambre, from the Eclipses of Jupiter's satellites, ought to be increased about a fortieth part. The Precession of the Equinoxes and Nutation. The Parallax of the fixed stars, which, by comparing a great number of Bradley's observations of the right ascensions of two stars on opposite meridians, (by which the effect is nearly doubled,) seems to be insensible.
But the most important part of the work is his excellent catalogue of 3222 fixed stars, in which the situation of each star is most commonly ascertained by several observations. In this catalogue he has given Flamsteed's numbers, their characters and magnitudes, also their right ascensions and declinations for the year 1755, with the annual precession for 1755 and 1800. The differences between the places of the stars and those in Piazzi's catalogue are likewise noted, with various references to other authors, who have observed the same stars. To this table is subjoined a smaller one of forty eight stars, observed by Bradley, which cannot now be found in the places where he had marked them. Several were, without doubt, inserted by mistake, like that of writing down a wrong hour or minute of the time of observation, as is evident from the remarks on this table by Bessel, Burg, and Burckhardt, in Zach's Monatliche Correspondenz. One