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to repeat the call before they fully understood, and then they gave three long and hearty cheers. I dipped my feet and washed my face and hands in the sea, and collected a few shells.... Thus have I through the instrumentality of Divine Providence been led to accomplish the great object of the expedition, and to take the whole party through, as witnesses to the fact, and through one of the finest countries man would wish to pass— good to the seacoast, with a stream of running water within half a mile of the sea. If this country is settled it will be one of the finest colonies under the Crown, suitable for the growth of any and everything. What a splendid country for producing cotton!" So having hoisted the Union Jack, and buried a record of the discovery at the foot of a tree on which their names were cut, they forthwith commenced the return journey.
This return was made over the same route. Many horses had been lost on the way, and thus the return was rendered proportionately difficult; but excepting some encounters with the natives, difficulties with respect to water, and such accidents, the journey presented nothing remarkable. Mr. Stuart himself, however, fell ill, and at one time scarcely expected to reach home alive. But early in January of the present year this gallant band did reach Adelaide, though Mr. Stuart was but in a weak state of health. Preparations were being made to give them an enthusiastic reception, for their fellow-colonists well know the difficulties of the exploration, and are able fully to appreciate the judgment and success with which it has been carried out.
VOL. II. NO. VIII.
Solar and Lunar Eclipses.- A partial solar and total lunar eclipse-the former on the evening of May 17, and the latter on the night of June 1have been favourably observed throughout the British Islands generally. The small portion of the solar surface eclipsed in the first (only 0.3 at London) produced little if any darkness or other phenomena, and observers could only notice the passage of the moon's disc over some of the spots, and the roughness of the moon's edges when projected on very strong light. The lunar eclipse was more interesting, and the gradual extinction of the moon's white light by umbra and penumbra, until only a dusky red patch was left in the sky, was more remarkable than any seen of late years. In some total eclipses of the moon it has been noticed that its surface is much brighter than on other occasions, and this has been held to be due to the distance of the moon from the earth at the time; i. e., if the moon be at its shortest distance, the shadow (being larger) will more completely envelope the moon, and the latter be in consequence darker, and vice versû. The moon was very near its perigee on the present occasion, so that the very considerable darkness observed may be taken as a further proof of this very natural explanation. The colour of the shadow on the moon was variable as the eclipse proceeded, being at first of an inky or greyish tint; but as the time of total eclipse approached, the hidden portion became gradually redder, the penumbra assuming a bluish colour, which is explained by the contrast between the red and light silvery part of the moon's disc; and the same effect was noticed as the shadow disappeared from the moon. The white spots on the floor of the mountain Plato were even conspicuous as the penumbra passed over that part. Another total eclipse of the moon will not be visible in England for some years, and it is but seldom that one is observed under such favourable circumstances.
Spectra of Stars.-Since Donati's memoir on this subject, published in the course of last year, it has engaged the attention of numerous observers; but the variety of detail seen by Secchi at the Roman Observatory (being probably favoured with a fine atmosphere at the time) is very remarkable, although, as yet, his determinations of the lines of only five stars have been published. Mr. Huggins and Dr. Miller have made a more extensive series on thirty or forty stars, and have been able to obtain microscopic photographs of Sirius and Capella. An ingenious method has been devised by
Mr. Huggins for observing the lines. He having found that the solar line D exactly corresponds with that of the sodium band, makes the latter the starting-point of his measures, having both it and the stellar spectrum which is to be examined, in the field at the same time. By these observations it is to be hoped that not only the chemical constitution but the temperature of the sun and stars may be determined, as it has been discovered that the length of the spectrum depends on the heat of the flame. M. Secchi makes use of Janssen's spectrometer of direct vision, and has been astonished at the magnificent results which he has obtained by it. In Alpha Orionis, he notices a line at F and four between F and G, only one of the latter of which is given by the Greenwich observations. The spectrum of Aldebaran extends still further, and sixteen lines of various breadths have been noticed in it. The spectra of Sirius and Rigel, which are white stars, are somewhat longer than those of the red stars, and the prominent lines appear in the blue and the violet, but are more rare in the less refrangible parts, with the exception of the red. It is remarkable, as Secchi observes, that the ray F is found in all the stars prominently as in the sun, and he considers its origin may be due to the terrestrial atmosphere. From the twenty stars observed at Greenwich, the majority give the same result; which is, however, equally well seen in the line G. There seem to be great anomalies in the different observations of spectra, which will doubtless be soon cleared away.
Companions to Bright Stars.-For some time past, observers have been endeavouring to detect faint stars in the immediate neighbourhood of bright ones, and have succeeded in many instances. Of those the companion of Sirius has been seen by the gigantic telescopes of Clark, Lassell, and Foucault. Latterly, M. Goldschmidt has not only succeeded in refinding it, but has also discovered five others, all of which are immerged in the light of Sirius, and one of them being nearly as close to the principal star as that discovered by Clark. MM. Barclay and Romberg have reobserved a small star close to Procyon, seen by Mr. Hind in 1855, and two other minute stars are noted, but their places not given. It would appear that some faint companions to Procyon have likewise been seen by M. Goldschmidt (vide “Les Mondes" of Feb.) Mr. Dawes says that one of the stars seen by M. Goldschmidt near Sirius is easily detected, but the five others could not be observed, and he thinks them atmospheric and not telescopic tests.
Mars. Mr. Lassell has made a valuable series of drawings of the planet Mars, taken during the late opposition, and has arrived at some remarkable conclusions in respect to its organism. He finds that whilst the same phase occurs every thirty-nine days, and the planet should appear exactly the same, the seas and continents can rarely be certainly recognized from his drawings, and is therefore of opinion that "if the variously coloured portions do generally represent land and water, their aspect must be greatly modified by the transit of clouds of great extent, density, and variety of form." The white spot at the North Pole was smaller than that of the South Pole. The ruddy portion was more uniform in appearance than the blue or green part, the only distinct marking on the red being a curved streak near the South Pole. On Nov. 4, it was noticed that the
bluish portion had a very irregular and hard outline in its darkest part, like the coast-line of a terrestrial continent broken by bays and inlets. Delicate markings were visible on the red and brown parts. Where the white part is near the margin, there appeared to be a protuberance at that part.
Fringes of Light during Solar Eclipses.-The appearance of moving fringes of light seen on a whitened wall during the total eclipse of Dec. 31, 1861, is remembered to have been seen by M. Goldschmidt in the annular eclipse of Sep. 7, 1820. He perceived them fully two and a half minutes before the annulus was formed. He was walking at the time in a direction from east to west, when he saw the moving shadows coming towards him slowly. The movement was not rapid, and the aspect like the shadows of smoke in sunshine; the forms being rhomboids of four or six inches in diameter, mixed up with ribbon-shaped shadows. The inner spaces were filled with round spots mixing gradually with the other in grey transparence. M. Goldschmidt saw this strange apparition whilst he walked for about one hundred steps, when the annulus was suddenly formed, the light of the sun running round the moon like a fluid. At the eclipse of July, 1860, these spots, yellow in colour, were noticed by a Spanish countryman flitting over his white dress from west to east, and the fringes were also seen during the same eclipse by Captain Mannheim in Africa.
Motion of Sun in Space.-From a consideration of the proper motions of stars in space, Sir W. Herschel, Argelander, Galloway, &c., determined that the sun was moving in the direction of the constellation of Hercules; and Struve has even calculated its annual motion towards that point. The Astronomer Royal, however, from discussing a larger series of observations from 1,167 stars, doubted this conclusion; and Mr. Dunkin, by pursuing the same calculations, has arrived at the same result. It may be stated that Mr. Carrington and Professor Fearnley consider it hopeless to determine this problem by investigating it by the method which the former has pointed out-viz., as to whether the direction of the motion of comets before coming into solar influence was different from the concluded motion of the sun. Mr. Carrington, therefore, advises the persevering observation and determinations of proper motions.
Lunar Mountain Plato.-When the moon is full, and circumstances are favourable, by making use of a moderately sized telescope, two or three bright spots may be seen on the otherwise dark surface of the interior of Plato. It was not known whether these were pits, or elevations above the surface. On the evening of April 26, however, Mr. Dawes saw them to great advantage, and they were proved to be veritable craters or pits with elevated surrounding wall, which cast a shadow outwards on one side and inwards on the other. The other round spots were found to assume a similar appearance. There are some other bright spots and streaks which, however, Mr. Dawes considers neither elevated above nor depressed below the surface, like those bright patches which are seen at other parts of the moon. Some of the round spots are so small that it has been impossible to determine whether they are craters or not.
The Lunar Mare Imbrium.—Mr. Birt points out that between the S.W.
part of the Alps as far as Plato, the Mare Imbrium is of a pure dark colour, the uniformity of tint being very remarkable, and not interrupted with bright patches, craters, and roughnesses, as in the other seas.
Occultation of the Star Kappa Cancri on April 26.-Mr. Copeland (near Manchester), in observing the disappearance of this star at the moon's dark limb, noticed that there was an interruption of its light. At first about three-fourths of its light disappeared instantly, and in the interval of half a second the remainer disappeared. This would seem to show that the star was double. The occultation of the star Alpha Scorpii, which is only visible as double to the most powerful instruments presenting the same phenomenon at occultation by the moon, Mr. Dawes has consequently examined Kappa Cancri with the hope of detecting this duplicity, but although seen pretty favourably and examined with magnifying powers of 620 and 1,000, the star seemed perfectly round. Occultations of this star occur on September 9 and November 30 of this year-the latter will be the most favourable for observation. It may be stated, however, that Mr. Burr observed the disappearance of this star on the same night at Highbury, and says that the star disappeared instantaneously.
Sun's Parallax.-This important element-in other words, the distance of the earth from the sun-has been lately determined by Mr. Stone, from a comparison of simultaneous observations of Mars and stars near him, made at the Greenwich and the Victoria (Australia) Observatories. The result gives 8,932 seconds, differing but little from the value found by M. Le Verrier, but very considerably from that of 8,578 deduced from the celebrated transits of Venus of 1761 and 1769.
Deviation in the Direction of Gravity.—The observed co-latitude of the Observatory of Moscow has been found to be eight seconds greater than that given by the geodetic survey; and as there can be no doubt of the correctness of either, it clearly proves a local deviation. As there are no mountains in the neighbourhood, but it is a clear level country, this is the more extraordinary.
Dark Ring of Saturn.-On March 26, 1863, Mr. Carpenter found a great increase in the brightness of the dusky ring of Saturn, which appeared to be nearly as bright as the illuminated ring.
Glass Specula.-The Rev. Mr. Key has invented a new method of polishing the above, which from its success in the hands of amateurs promises excellent results. He polishes to a spherical figure first, and then modifies the figure of the polisher, with which, with the usual stroke and side-motion, he obtains the parabolic figure. By means of a 64-inch aperture, Mr. With, of Hereford, has worked one which separates the components of the small star of Gamma Andromedæ.
Parallax of Stars.-M. Krüger has determined the parallax of two new stars of which M. Argelander had established the considerable proper motion. The first is Lalande, 21,258, for which the annual parallax has been found to be 0.260 seconds of arc. The second is Argelander's star, 17.415-6, for which he finds almost the same amount-viz., 0.247 seconds. It is somewhat remarkable that both of those are stars invisible to the naked eye-the first being of the 8 and the second of the 9th magnitude. This would seem to show, which has already been established by 61