salt and pepper. The result was exceedingly satisfactory; and finding this immense fungus more than our family could consume whilst it remained fresh, we invited our friends to partake, and they were as delighted as ourselves with the new breakfast relish, to them and to usthe first, but we hope not the last experiment upon a fried puff-ball.”

Mr. Cooke employs such excellent material, that we are not surprised that he can make a good dish out of a puff-ball. His skill reminds us of French cookery, which is so celebrated for its metamorphosis into excellent eating of what to an Englishman would be exceedingly unpalatable.

Allowing for a certain amount of enthusiasm so pardonable in Mr. Cooke as a naturalist, we cheerfully commend the book to public favour, as probably containing much that is true, and we think that money may be saved and no person's health endangered by its purchase, careful perusal, and a trial of its numerous suggestions.

The Microscope and its Revelations. By W. B. CARPENTER, M.D., F.R.S., &c. Third Edition. Churchill.

THE

HIS new edition of Dr. Carpenter's work contains an account of the most recent researches of microscopical writers and observers, and although it is many years since the first edition was published, this still remains the best text-book of microscopical science extant, and (together with Mr. Van Voorst's Micrographic Dictionary) forms the best existing guide for all classes of students.

262

SCIENTIFIC SUMMARY.

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QUARTERLY RETROSPECT.

ASTRONOMY.

URING the long nights of the winter months, the telescopic observer

is much busier than at other seasons of the year; and although the present quarter has been far from favourable, yet a few discoveries have been made which are somewhat important. M. D'Arrest has inaugurated the erection of a large Munich refractor, at Copenhagen, by the discovery of the seventy-sixth individual of the group of planets revolving round the sun between Mars and Jupiter. His successor at the Leipzic Observatory-M. Bruhns-has signally distinguished himself as the discoverer of two comets within a few hours of each other, and thus proved that this branch of astronomy is equally safe in his hands as in those of M. D'Arrest, so famous for his successful search after those bodies. In this, however, M. Bruhns is only following up his previous well-earned renown at the Berlin Observatory, where he detected many comets. By the public in general those discoveries are looked upon as the result of chance; but this is far from being the case, the search being as systematic as any that can possibly take place under the circumstances. Previous to finding either a planet or comet, the sky has to be sounded, surveyed and triangulated with the greatest accuracy-variable stars and nebulæ avoided, and marked with as great care as the rocks and breakers of the ocean-and the result has been that within the last ten years the maps of the smaller telescopic stars are far more correct than those which are visible to the naked eye. It would appear probable that the list of planets is now nearly full,—the perfection of the star-maps does not seem to have any effect in adding to their number, although it is by this perfection that any loose straggler is in momentary danger of being detected. Of late years, those planetary "nuggets" have been found few and far between, contrasting strongly with the rich harvest gathered some years since by MM. Hind, Goldschmidt, and Gasparis. In regard to comets the case is otherwise, and we may always expect an average annual supply of those bodies. In consequence of cloudy weather and moonlight, neither of the new comets has been favourably seen in this country, so that we must defer any further notice of them for the present.

Daphne. The planet Daphne has been searched for during the last three or four years with great anxiety, but no tidings heard of it until the last few months, when Dr. Luther detected an object of the eleventh magnitude

(on August 31), which turned out to be the missing planet. During the search instituted for it, another planet (the 56th of the asteroids) was detected, which received the name of Pseudo-Daphne. This asteroid has, therefore, the distinguished honour of being No. 41, No. 56, and No. 75, of the group of asteroids, two of which numerals it must now be contented to relinquish. From observations on August 31, September 5, and September 11, there can be no doubt of its identity with the original object. PseudoDaphne has received the name of Melete; the planets 73 and 74 discovered on April 7 and August 29 respectively, being called Clytia and Galatea.

Lunar Mountains.-Mr. Birt has detected a remarkable chain of lunar craters which have been overlooked by Mädler and Schröter, and whose positions are not given in any other maps of the moon. They are situated on the surface of the Mare Tranquillitatis, being the highest portion of the wall between Menelaus to a point opposite Plinius, and situated on the southern border of the Mare Serenitatis. It is very seldom that they can be advantageously seen, and Mr. Birt was only able to observe them in 1861, April 16, and 1862, May 5 and October 29. On May 5, 1862, he noticed that there were three deep craters, hardly distinguishable from each other, being quite in shadow; two rocks and another crater, which is isolated from the further continuation of this wall, were also seen, they being all situated at the end of the promontory called Acherusia. Mr. Birt has recognized other discrepancies in Beer and Mädler's maps, but does not consider them to be real changes, the great difficulty of seeing them fully accounting for their omission.

The Elchies Telescope.-The great equatorial of Ross, furnished with a telescope of eleven inches aperture and sixteen feet of focal length, has been almost lost sight of since its appearance at the Exhibition of 1851. It has of late years been in the possession of J. W. Grant, Esq., of Elchies, Morayshire, who, however, has been unable to make as much use of it as he could wish, or as his former success with a five-foot telescope in India would lead one to anticipate-he having with the latter instrument discovered the companion to Antares two years before Professor Mitchell, who was furnished with the great Cincinnati refractor.

Professor Smyth, who examined the optical and mechanical arrangements of the Elchies telescope, reports highly on both qualities. When it is considered that one portion of the stand alone weighs eleven tons, its firmness and absence from tremor may be imagined. In the double star 28 Aquile, Professor Smyth detected a new or third companion, which is an exceedingly faint object, at nearly the same distance from the large star as the other one. In the triple star Delta Aquila, the closer companion was identified, but it was found that it had decreased in brilliancy, from the twelfth magnitude in 1833, to the sixteenth in 1862. Two new stars of the fifteenth magnitude were detected at 61 and 107 seconds from the principal star in the beautiful system of Beta Cygni. A faint companion of the same magnitude was discovered within 70 seconds of Zeta Sagittæ. New stars were also detected in the neighbourhood of 452 Cygni and 1 Pegasi, at the respective distances of 98 and 80 seconds from the principal star, and three new ones were found to accompany 312 Pegasi, at the distances of 81, 106, and 127 seconds respectively. In the

star 222 Arietis, great changes have taken place since 1834,-the principal star of the sixth magnitude, and visible to the naked eye, having vanished completely; whilst the three others, which in 1834 were of the fifteenth, tenth, and ninth magnitudes respectively, when viewed through the Elchies telescope, were found to be two of the twelfth, and the last of seven and a half magnitudes. This may serve as an example of the continual and usually unnoticed changes which are taking place in the heavens. As a crucial experiment of the defining power of the telescope, it may be stated that the blue star of Gamma Andromeda was completely and more than separated. Scarcely more than half a dozen of the best instruments in the world at the present time would be able to effect this separation.

Great Comet of 1861.-The Rev. Mr. Webb has recently given the result of his observations on the comet of 1861, in regard to the nucleus, envelopes, the luminous sector or fan, the coma, and the tail. The envelopes were the most remarkable portion of the comet, particularly on the night of June 30, when the effect produced was compared to a number of light, hazy clouds, floating around a miniature full moon, and when portions of six of various lengths and degrees of curvature could be distinctly traced. From a general résumé of his observations made up to July 23, Mr. Webb is of opinion that as no phase was visible in the nucleus, that this part "either contained no concentration of opaque matter or shone by intrinsic light." The axial rotation of the nucleus also seems improbable, but it would appear probable that there was some amount of libration if we were to judge by the swinging motion of the sector. The latter was of later date than the envelopes and much posterior to the perihelion passage; as the comet retreated from the sun, the envelopes descended on the nucleus, and caused perhaps the increasing apparent density of the whole coma. No indications of rotation were perceived in the tail. The angle which the sector and envelopes made with the axis of the tail would lead one to suppose that a stronger repulsion or a less resisted emissive force acted in one direction from the nucleus than in the opposite. The nebulous veils were always seen better on one side than on the other, but from the position of the comet in its orbit no satisfactory deductions can be made in this respect.

According to wishes expressed by correspondents, we append the elements of the first and second comets of this year.-The first, discovered by M. Schmidt, at Athens, on July 2, near the stars Beta, Rho, and Sigma Cassiopeiæ, was at its shortest distance from the sun on June 22, 5′ 43, Greenwich mean time. The longitudes of node and perihelion were respectively 324° 30' and 298° 35'. The inclination was 8° 14', the motion retrograde, and the logarithm of least distance 9.992. The second comet of 1862 passed its perihelion on August 23, 7·1 Berlin mean time, the longitudes of node and perihelion being 137° 5' and 344° 16, the inclination of orbit 66° 3′; motion retrograde, and the logarithm of least distance being 9.985.

Companion to Procyon.-The existence of dark stars in the heavens, which controlled the motions of those visible to the eye, which idea is due to Bessel, was good-humouredly ridiculed by Humboldt in his correspondence with the former. It is now, however, made a matter of

calculation, in at least two stars, Sirius and Procyon. In respect to the former star, Peters in 1851 found that the irregularities in its position could be explained by the motion of the bright star about an invisible one, the latter being in uniform motion.

In respect to Procyon, Bessel's hypothesis has also been confirmed, and a binary system in which Procyon moves about a dark star in an orbit whose plane is that of the visible heavens, the distance between the components being about a second and a quarter. The actual distance of Procyon from the Sun being approximately known, M. Auwers concludes that the mass of the dark body is about one-half of that of the Sun, and in any case the mass of the dark body must be at least a hundred times as great as that of Jupiter. If Procyon and its companion have equal masses, that of each would be greater than ths of the Sun; and if the mass of Procyon is equal to that of the Sun, that of its companion must be greater than 9ths that of the Sun.

Mars.-By observations made at the Oxford Observatory between September 18 and October 26 of the present year, Mr. Main has determined the ratio of the polar to the equatorial diameters of Mars as 38 to 39, being almost exactly the same as found by Arago, and which has been so much doubted. On September 30, the ellipticity was found as 245 to 244, and on October 17, as 29 to 28, which are the extremes. For the equatorial diameter at the unit of the distance, Mr. Main finds 9"-38, giving a real diameter to the planet of 4,332 miles.

Comet II. of 1862.-This comet was observed at Hobart Town until September 21, with the naked eye, at which time, of course, it was not at all visible in the north of Europe. Mr. Knott found variations in the position of the luminous sector to the extent of more than fifty degrees.

Star-Cluster in the Southern Cross.-This object, described by Sir John Herschel as resembling a splendid piece of jewellery (the stars in it being compared, from their various and beautiful tints, to sapphires, rubies, topaz, and emeralds), appears to have greatly altered of late years: one has changed, according to the careful observations of Mr. Abbott, from greenish-white to bluish-purple; another from green to pale cobalt; another from green to ultramarine, &c. The colour of stars is, however, so variously judged by different eyes, that probably the above discrepancies are due more to different estimations than any real change.

Suspected Variable Star.-In searching for one of Herschel's triple stars, which could not be recognized as such by Struve, with the great Dorpat telescope, Mr. Dawes immediately perceived the looked-for companion, which was equally unseen by South, Sir John Herschel, and Smyth. From the fact of its being invisible for eighty years in powerful instruments and well-trained observers, and seen in the present year with a telescope of four inches aperture, Mr. Dawes thinks it desirable that it should be put down upon the list of suspected variables. The position of this object is R.A., 19h. 29m.; N.P.D., 100° 32'; the magnitudes, according to Mr. Dawes, 6, 8, and 114.

Large Meteor.-A huge bolide made its appearance on November 27, which was visible in all parts of the British Islands and France. As seen by the writer, it appeared as a huge globe of fire of a balloon shape, almost

VOL II.-NO. VI.

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