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more usual to employ Lagrange's mode of deriving them from the different orders of fluxions.

XLIII. Chladni's Remarks on Cosmological Circumstances.

The author collects several accounts of dark substances passing over the sun, though foreign to the solar system; and of temporary stars, one of which he suspects may have appeared periodically. But the most interesting part of the paper is the notice of some observations of Fraunhofer on the light of the stars, published in the 56th volume of Gilbert's Annals, but hitherto little known in this country. Fraunhofer has discovered, it seems, more than 500 dark streaks crossing the spectrum into which the solar light is expanded by a prism, and of which he gives a figure; not being, perhaps, aware that they had been before observed by Dr. Wollaston: but the novelty is, that each fixed star has a peculiar arrangement of the streaks, so that this experiment indicates a new mode of distinguishing lights apparently of precisely the same nature. Dr. Wollaston has noticed a still more marked interruption of the spectrum produced by the blue light of a candle; and Dr. Young has observed a similar appearance in light transmitted by several kinds of coloured glasses.

XLIV. Brandes on the mean Temperature of the different Times of the Year.

Professor Brandes has computed the mean temperatures for intervals of five days, from the Journal of the Royal Society in London, for two periods of five years each. He has remarked that in London, as well as at Stockholm, there is a temporary elevation towards the beginning, and a depression towards the middle of February: but a similar variation which he notices in March may, perhaps, be partly dependent on the hour at which the thermometer was observed.

iv. JULY and AUGUST.

I. Littrow on the Right Ascension of the principal Fixed Stars. Deduced from all the observations in the first and second

volume of Bessel's publication. The places finally obtained agree very nearly with a catalogue deduced from a smaller number of observations by Bessel himself, which he has lately sent over to this country. The most probable error, according to Professor Littrow's calculation, never amounts to the hundredth of a second of time; the correction of Bessel's former determination never to 1".

II. An Attempt to determine the most probable Orbit of the Comet of 1680.

A very elaborate essay, continued to the next Number. The author remarks that the whole of Flamsteed and Newton's observations may be represented without an error of more than about 20" of space; and he has rejected those of many other persons, which exhibited errors of from 5' to 10'. The period is supposed to be 1589,2 Julian years.

III. Bohnenberger on a Problem in Practical Geometry.

A convenient mode of finding, upon a plain table, a point from which three other points subtend given angles.

V. SEPTEMBER and OCTOBER.

IV. Continuation of the Essay on the Comet.

From a very laborious investigation of all the observations, and a comparison of their probable values; the corrected period is found 8814 Julian years, the greatest probable limits of its uncertainty being 6179 and 14030. The mean error of the observations is only half as great on this hypothesis, as upon Halley's, of a period of about 575 years; and as Bessel has observed, the very circumstance of the accuracy of the recurrence at three successive periods of 575 years, is of itself an improbability, since the planetary perturbations must, in general, have altered the period from time to time as much as four or five years.

V. Sequel of Piazzi's Life.

Piazzi was born 19th March, 1746. The principal events of

his life are recorded in the Monthly Correspondence for 1810. Among the later occurrences, the first that is here mentioned is his being appointed to examine the state of the weights and measures of Sicily, and his giving the preference to a system of binary subdivision, founded on the measures already employed at Palermo, in preference to the decimal system of the French. His various astronomical discoveries and publications are as universally esteemed as they are elaborate and important; and he has still the happiness of enjoying his faculties wholly unimpaired, at the advanced age which he has attained.

VI. Bessel's Formulas for the computation of Nutation and Aberration.

The subject of this essay is of great importance to the cultivation of the more refined departments of astronomy, and the ingenious author has bestowed on it no common share of industry and accuracy but his investigations appear to be somewhat unnecessarily complicated, and it will be practicable to introduce the only material parts of them into a demonstration conducted in a more geometrical and more intelligible form. [See Art. II. page 21.]

VII. Littrow on the Eclipse of the 7th September, 1820.

Tables showing the path of the shadow in this remarkable eclipse, and the times of its beginning and end for all the principal parts of Germany. The author has also given a very convenient formula for finding the apparent time of the beginning and end at any other place, of which the longitude E. from Paris in hours is h, and the latitude in degrees d; the beginning, in the time of the place in question, being 2,412 +1,304 d —,03504 d; and the end 5,550 +1,102 h—,03999 b; and the angle made, at the beginning of the eclipse, by the line joining the centres with the vertical line, being 52°,359 + 28,463 h. Thus, for Greenwich we have h,1555, d 51,478, and the beginning 24', the end 3.19'; the Nautical Almanac giving 24'4, and 3.16, respectively. For Paris, h 0, d 48,837, and the beginning is at 42', the end 3.35; while the Connaissance

des Tems has 47' and 3.35': these differences rather exceeding the limits of inaccuracy assigned by the author to his formula.

VIII. Geocentric Places of Pallas, by Dirksen.

Up to June, 1820. The next opposition will 1820, Jan. 6, 20. 16′. 41", mean time of Gottingen; longitude 106° . 0′.16′′,2, geocentric latitude 54°. 28′ 33′′,2 S.

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IX. Extracts of Letters from the Chevalier Bürg.

Observations of the oppositions of the Georgian planet, and of Jupiter; a calculation of the eclipse of 1820, for Vienna and Gratz, agreeing within two or three minutes only with Littrow's table. The second letter is dated 5th Feb. 1819, and relates to some comets, and to an opposition of Vesta, differing from Daussy's tables only 23" in heliocentric longitude, and 18′′ in latitude; there are also some oppositions of the other planets.

X. Extract of a Letter from Professor Schumacher. Relating to Vesta, and to some geographical observations.

S. B. L.

ART. VII. On the Mammoth, or Fossil Elephant, found in the Ice, at the Mouth of the River Lena, in Siberia. From the Fifth Volume of the Memoirs of the Imperial Academy of Sciences of St. Petersburg.

[THE following pages are translated and abridged from a paper by Dr. Tilesius in the Memoirs of the Petersburg Academy, and the figure of the skeleton is faithfully copied, but of a reduced size, from the large plate which accompanies it.

The term "Mammoth, or Fossil Elephant" has been made use of with a view to correct a common mistake in the application of the word Mammoth, which is in England frequently given to the Mastodon of Cuvier, the animal of which the remains are chiefly found on the banks of the Ohio and in other parts of America. The Siberians have long applied the name of "Mammoth" to the elephant whose bones are

very abundant in that country, and in many other parts of the world, and it is so used by writers on the Continent. These remains, wherever found, belong to a species of elephant different from the two now living on the globe, and which is called by Cuvier "the Fossil Elephant:" but the propriety of applying the term fossil to the subject of the following memoir may perhaps be doubted; for although it is of the same species, it was not found beneath the surface of the earth, but in ice, and retained its flesh and all its softer parts in a state of perfect freshness.

A very complete dissertation on the fossil and living elephants, by M. Cuvier, is inserted in the eighth volume of the Annales du Muséum d'Histoire Naturelle, and has been re-published in his Recherches sur les Ossemens fossiles de Quadrupèdes.]

ACCORDING to several writers, the term Mammoth is of Tartar origin, and is derived from mama, which signifies the earth, and the natives of Siberia give the name of "bones of the Mammoth" to the remains of elephants which are found in great abundance in that country, believing that the Mammoth is an animal which lives underground at the present time.

The Mammoth, or elephant's bones and tusks, are found throughout Russia, and more particularly in Eastern Siberia and the Arctic marshes. The tusks are found in great quantities, and are collected for the sake of profit, being sold to the turners in the place of the living ivory of Africa and the warmer parts of Asia, to which it is not at all inferior.

Almost the whole of the ivory-turners' work made in Russia is from the Siberian fossil ivory, and sometimes the tusks, having hitherto always been found in abundance, are exported rom thence, being less in price than the recent. Although, for a long series of years, very many thousands have been annually obtained, yet they are still collected every year in great numbers on the banks of the larger rivers of the Russian empire, and more particularly those of further Siberia, They abound most of all in the Laichovian Isles and on the shores of the Frozen Sea.

According to others, it is derived from behemoth, mentioned inthe book of Job; or mehemoth, an epithet which the Arabs commonly add to the word Elephant, to designate one which is very large. See Cuvier, Ann, du Mus. vol. 8, p. 45.

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