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planet distant. Some other valuable observations on Neptune have been made; but the existence of its suspected ring has not been confirmed.

A considerable number of COMETS have rewarded the diligence of observers. Dr. Petersen, assistant-astronomer to Professor Schumacher, at Altona, claims the honours of no less than three of these visitors. The first he detected on the night of the 7th August, 1849, in Auriga; the second on the evening of the 26th October of the same year in Draco; the third on the 1st May, 1850.

Another comet was discovered almost simultaneously by three astronomers in three very distant parts of the globe. By M. Schweitzer on the 11th April, 1850, at Moscow; by Professor Bond at Cambridge, U. S., on the same day a few hours later; and by Mr. Graham, at Markree, on the 14th of the same month. M. Goujon, of the observatory at Paris, detected a comet on the night of the 15th April. Another comet was observed by Mr. Bond, jun., at Cambridge, U. S., on the 29th August. It was also seen by European observers a few days

later.

The reappearance of Encke's periodical comet was detected on the 27th August, 1848, by Professor Bond, of Cambridge, U. S. It presented much the same appearance as in 1828 and 1838; its general outline being elliptical, with a very sensible condensation of light on the side next the sun.

The periodical comet of Faye has also reappeared in gratifying accordance with the prediction. Its ephemeris had been calculated by Lieut. Stratford, and his calculations had been examined by VOL. XCII.

M. Le Verrier, who added the perturbations due to planetary attraction-a correction to the mean motion necessary to bring about a perfect accordance between theory and observation. The observations of Professor Challis, who detected it, confirm the accuracy of these calculations, and afford a gratifying proof of the progress which has been made in the theory and practice of this department of astronomy.

As

The disappearance of Saturn's ring (by its presenting its thin edge to the Earth), during the year 1848, was attended with some singular phenomena. Breaks or inequalities, such as would arise from irregularities in its structure were the matter of which it is composed unequally distributed in its different parts, were observed, when the edge only of the ring was visible. Hitherto these appearances have been noticed only on the illuminated side, but now on the unilluminated side also. these irregularities always retain one fixed position in reference to the globe of Saturn, the inference is, that the breaks in the illumination of the edge do not rotate about the ball. The first disappearance of the ring took place about the 30th June, and it reappeared between Aug. 31, and Sept. 3. It disappeared a second time between Sept. 12 and Sept. 13, and reappeared between Jan. 18 and Jan. 19, 1849. Much difference of opinion exists as to the form of this planet. Sir W. Herschel was of opinion that it was not elliptical, but like a parallelogram with the corners rounded off, and that the northern and southern regions were of a different shape: in the latter opinion his son Sir J. Herschel coincided. A series of mi2 F

crometrical observations made by Mr. Main during the disappearance of the ring, shows that the form of Saturn without his ring is a perfect ellipse of considerable ellipticity. M. Lassell and Mr. Dawes have further made such observations upon the ring, that they became perfectly satisfied of its division into two distinct annuli, having obtained a perfectly clear and satisfactory view of the division. But a new and inexplicable phenomenon was added to the other marvels of this planet at the end of the year 1850. It was announced that Mr. Bond of Cambridge, U. S., had, on the night of the 15th November, discovered a third ring interior to the two others, and therefore at no great distance from the body of the planet. On the 3rd December, the Rev. Mr. Dawes and M. Lassell, examining Saturn at the private observatory of the former at Wateringbury, perceived phenomena analogous to those noticed by Mr. Bond; it appeared as though something like a crape veil covered a part of the sky within the inner (i. e. the second) ring, separated by a darker ill-defined boundary line from the solid body of the ring. Whether this be an innermost ring, or what other explanation may be assigned to it, these appearances are especially remarkable, because, in 1791 and the following years, Sir W. Herschel paid particular attention to the phenomena of this planet, and his observations amount to a negation of these of 1850 being then presented. It has been conjectured that they may be due to the total absence of sunshine from the southern side of the ring for the last fifteen years; a condition from which it has just emerged.

A transit of Mercury over the Sun's disc, Nov. 8-9, 1848, was very carefully observed at most of the observatories, and afforded some curious phenomena. The passage of Jupiter's fourth satellite over the disc of its primary, in like manner, called general attention, and the somewhat singular phenomena which were exhibited were carefully noted.

At

A total eclipse of the Moon on the night of the 19th March, 1849, was accompanied by circumstances which do not appear to have been heretofore remarked — certainly not to the same degree. Bruges, during the whole period. of the adumbration, the shaded surface presented a degree of light quite unusual; it was of a deep red or copper colour, and even during the period of total eclipse the light and dark places on the face of the moon could be almost as well made out as in an ordinary dull moonlight night. The British Consul at Ghent, who was not aware that an eclipse was expected, wrote for an explanation of the blood-red colour of the moon at 9 o'clock. In England this appearance was less marked. Professor Challis, at Cambridge, describes it as "a faint ruddy light spread over the eclipsed portion of the moon's disc." Mr. Hind, at the South Villa observatory, says, "nothing unusual was remarked; the shadow had a greenish tinge." At Killaloe the colour "was much like that of tarnished yellow." Mr. Walkley, who observed the eclipse at Collumpton, says, that the appearances were as usual until twenty minutes to 9 o'clock; at that period, and for the space of the next hour, instead of an eclipse, the whole phase of that body became very quickly and most beau

tifully illuminated, and assumed the appearance of the glowing heat of fire from the furnace, rather tinged with a deep red. The whole disc of the moon was as perfect with light as if there had been no eclipse whatever." During the period of the eclipse there was a bright aurora in the north, and at Bruges a most magnificent meteor descended obliquely towards the horizon about the time of the central eclipse.

Some very valuable treatises on Astronomical Science have been published within the last three years. Those which appear periodically and officially, it is not here necessary to notice; they all contain valuable contributions to the stores of the science. The reductions of the Greenwich lunar observations from 1750 to 1830 have been completed and published, a work, which, for magnitude, as directed to a special object, and for accuracy, has scarcely ever been equalled. The sixteenth volume of Cambridge Observations, containing the meridian observations of 1844 and 1845, and a volume of the Edinburgh Astronomical Observations, that for 1843, have been published. The observations of the late Mr. Fallows, made at the Cape of Good Hope in the years 1829, 1830, and 1831, have been printed at the expense of the Government. They were placed in the hands of the Astronomer Royal for reduction and exhibition in proper form; the work thus ably edited is regarded as the foundation of astronomy in the southern hemisphere.

Some additions of great importance in the instruments and mechanical appliances of the science are worthy of note. At the Royal Observatory at Greenwich, a transit

circle, with a telescope of eight inches aperture, has been substituted for the transit instrument and mural circle. For this operation no ordinary science, care, and mechanical ingenuity were required. An altitude and azimuth instrument, of remarkably massive and firm construction, has also been mounted at the Royal Observatory for the express purpose of observing the moon on every day on which it is at any time visible. At the Radcliffe Observatory, Oxford, an heliometer, by Repsold, has been erected in a building constructed purposely to receive it. The diameter of the dividing objectglass is 7 inches, with a focal length of 10 feet 4 inches. The hour-circle and declination-circle are each 2 feet in diameter.

A new observatory has been founded and built at Liverpool. This building is constructed and furnished with instruments chiefly by the liberality of the Town Council; besides a convenient house for the Astronomer, it contains a transit-room, an equatorial-room with a revolving dome, a chronometer-room, and a computing-room. The transit instrument has a telescope of 5 feet focus and 4 inches aperture; a transit clock and a mean-time clock by Molineux. The equatorial is a very fine instrument; the object-glass by Merz, of Munich, is 8 French inches in aperture, and about 12 feet in focal length. The clock-work is of most ingenious construction, having water for its motive power. Mr. Hartnup is appointed the first Director.

The most gigantic instrument of the present day, and that by which the period will perhaps be most distinguished to future ages

is Lord Rosse's 6-feet reflector. Some defects in the mounting of the mirror have been remedied, and this wonderful example of the love of science will now come into operation.

A very remarkable example of the connection of the sciences with each other, or at least of the manner in which each may be made available for the purposes of the other, is exhibited in America by

the application of the electric telegraph to the determination of differences of terrestrial longitude. By means of this wonderful instrument, the differences of the longitudes of the cities of Louisville, Cincinnati, and Pittsburg, have been not only observed but recorded.

The same instrument has also been most successfully applied to observing and recording transits.

THE ARCTIC EXPEDITION.

SEARCH FOR SIR JOHN FRANKLIN.

IT is superfluous to do more than
remind the reader that the great
object proposed by Columbus, both
to himself and to the sovereigns
to whom he offered his plans, was
the opening of a passage to the
Indies by a voyage over the sea
to the westward; and that in the
course of his navigation he reached
the shores of the New World.
The occupation of the islands and
main of central and southern Ame-
rica by the Spaniards and Portu-
guese, precluded the other nations
of Europe from following this
course, and drove them to the
north, where the discovery of the
extensive lands, bays, and gulfs of
North America rewarded their ad-
venture, and suggested the noble
idea that by reaching the northern
extremity of the land, and circum-
navigating the coasts, a north
western passage to the Indies might
be found, which should lay open
the fabulous wealth of those re-
gions to the commercial states of
Europe. This notion was eagerly
adopted, and produced a race of
intrepid commanders and seamen,
who underwent incredible hard-
ships and dangers in the frozen
seas to which their adventures led
them, and was probably the cause
of the great advance the modern
nations have made in all that be-
longs to navigation. The dangers
and losses which were incurred

in these voyages, and the failure
in which they necessarily ended,
would probably have put a stop to
further undertakings, had it not
happened that our merchant ad-
venturers discovered that these
ungenial regions were productive
of valuable merchandise in oils,
furs, and teeth, which repaid their
outfit, and incited to new attempts.
Thus incessant and daring voyages
were made by merchants and cap-
tains, who combined traffic with
exploration, and our knowledge of
those parts of the earth was en-
larged by the discoveries of Hud-
son, Davis, Baffin, and other in-
Nevertheless
trepid navigators.

the one great prominent object of
the recorded voyages to the north
was undoubtedly the discovery of
a north-west passage to the Indies;
the motive which inspired Cabot
and his self-seeking master, and
the gallant English commanders
who have for three centuries per-
severed in the attempt;-in our
times, indeed, the commercial view
has disappeared from the evident.
inutility of such a passage should
it be found to exist, and the search
is persevered in for the purpose of
solving a geographical problem
and for scientific purposes, and
also from a dogged resolution to
carry through an undertaking
which has become associated with
English enterprise.

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