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eclipse-observations indicated a change in the generally observed under favorable conditions. color and appearance of the corona. The gas Prof. S. P. Langley of Allegheny, Pa., saw the eous elements were much less conspicuous than entire disk of Mercury outside the sun at least in the eclipses of 1869, 1870, and 1871, near half a minute before the first external conthe epoch of sun-spot maximum. In short, tact. This visibility was regarded as due to the conclusion of most astronomers is that the brightness of the coronal background. A the non-gaseous matter of the corona is cos remarkable difference was noticed between mical, while the gaseous elements so conspicu- the apparent size of the planet before and ous in eclipses at the epochs of spot maxima after its entrance upon the sun; the former are strictly solar, consisting of torrents thrown being greater than the latter in the ratio of out to great distances by the sun's eruptive five to four. Prof. Langley saw no “black force. “In spot-maximum years,” says Mr. drop"nor "ligament.” He failed also to see Lockyer, "we have violent up-rushes of gas the central bright spot, as well as the aureola from the sun's interior, and the corona is main- around the planet-phenomena observed by ly built up of such gas. Further, we have several other astronomers. spots, and, if these are not evidences of the re A comparison of the best contact-observaturn convection currents, we have none other. tions obtained at different stations gave new In spot-minimum years, such as the present, evidence in favor of Leverrier's theory of the we have no up-rushes, and the corona contains motion of Mercury's perihelion, and of the exno gas, and there are no spots. Spots, then, istence of a cause of perturbation between are only observed when we have a right to Mercury and the sun. look for the return of the upward current, Relative Brightness of Venus and Mercury. about which there is no doubt, and the rate of On September 26, 1878, Mercury and Vewhich we have measured.”
nus were so close together that they were The serrations known as Baily's beads re- telescopically in the same field of view. Mr. mained visible, according to Mr. Colbert, for James Nasmyth of Kent, England, improved two and a half seconds, indicating that the this favorable circumstance by making careful mountains around the moon's disk are one and comparisons of the relative brightness of the a half mile high.
two planets. The result of the observation The Relation between Sun-spot Frequency was that Mercury has less than half the brightand Changes in the Earth's Atmosphere. The ness of Venus, or, in other words, less than half "American Journal of Science” for June, the reflective power. This relative deficiency 1878, contains a letter from Dr. B. A. Gould, is the more remarkable when it is considered Director of the Cordoba (S. A.) Observatory, that, in consequence of Mercury's nearness to announcing the probable discovery of a mutual the sun, its brightness ought to be nearly four relation between the number of sun-spots and times greater than that of Venus. The fact the condition of the earth's atmosphere. Dur seems to indicate an important difference being the first two or three years of Dr. Gould's tween the atmospheres of the two planets. residence at Cordoba—at the epoch of sun The Satellites of Mars.—In a memoir respot maximum—the state of the atmosphere cently published by the Washington Observawas eminently favorable for astronomical ob- tory, Prof. Asaph Hall has discussed all the servations. With the change, however, in the observations of the satellites of Mars, and has condition of the sun's surface, a simultaneous determined the elements of their orbits within variation occurred in the atmosphere and mean very narrow limits of probable error. The temperature of Buenos Ayres and the Argen- name Phobos has been adopted by Prof. Hall tine Republic. In 1877 there were but ten for the inner satellite, and that of Deimos for clear nights at Cordoba during the months of the outer. In brightness the former is rated March and April, while in July and August by the discoverer as an 114-magnitude star; the number was still less; and from January 1 the latter as of the 12th. The diameter of to March 20, 1878, there was but one clear Deimos is estimated by Prof. Pickering of night. In Dr. Gould's view these strong con Harvard Observatory at six miles, that of Photrasts indicate periodic fluctuations, and an bos at seven. At Washington alone 43 obserelaborate discussion of the facts at his dispo- vations of Phobos and 52 of Deimos were obsal sustains the theory of a mutual relation. tained up to October 25th, when they could no " It is manifest,” Dr. Gould remarks, “ that longer be detected by the 26-inch equatorial. if the variations of the terrestrial temperature the periods and eccentricities derived from follow those of the sun-spots, and are thus ade- these observations are as follows: quate to account for the correspondence observed between these and the variations of the Period.
Th. 39m. 15.07s. 30h. 17m. 53.SCg. Wagnetic declination, all necessity for assum
Eccentricity. ing any direct and transcendental connection Not only are the orbits approximately circubetween this latter and the disturbance of the lar, but the planes of both are very nearly cosolar surface disappears."
incident with the equator of Mars. The mass The Transit of Mercury.-A transit of Mer- of Mars obtained from the Washington obcury occurred on the 6th of May, 1878, the pas- servations is 3,703,500 sage occupying 7h. 33. The phenomenon was llinor Planets.-Twelve minor planets were
Date of disc.
Place of disc. Mag.
151 162 193
7 Palisa 66
155 186 187
discovered in 1878, bringing the number up to star. It is interesting to record that this faint tenth191. The dates and places of discovery, to- magnitude star was not even dimmed, much less gether with the names of the discoverers, are
obliterated, by the interposition of the densest part
of the comet; it shone right through the center and given in the following table:
most condensed part as bright as it had before appeared against the dark background of the sky. The other star of the same magnitude in the field formed
an accurate standard of comparison by which to de180)
Jan. 29 Perrotin Toulouse 12:0 terinine any diminution of light in the former.
The Origin of Comets. — The “American 1st Deiopeia
Journal of Science” for September, 1878, con-
comets, by Prof. II. A. Newton of Yale Col185 Menippe June 26 Peters
Clinton 120 lege. In the theory of Kant comets as well as Phthia Sept. 9
11:0 planets were originally parts of the nebulous Ismeno 191 Kolga
10.5 mass from which the solar system was formed.
Laplace, on the other hand, regarded them as The following minor planets, discovered in of extraneous origin. Prof. Newton discusses 1877, have been named since the issue of our
such cometary phenomena as have an obvious last volume: No. 171, Ophelia ; 172, Baucis; bearing on this interesting question, and finds . and 178, Belisana.
a decided preponderance of evidence in favor The Muss of Saturn's Rings. — In the of a foreign origin. lle grants, howerer, that “Comptes Rendus,” vol. lxxxv., No. 16, M. the group of comets with periods correspondTisserand has given a new determination of ing with those of the minor planets may have the mass of Saturn's rings. Bessel's value of originated in the solar nebula. the mass was found from its disturbing effect
Veteoric Showers. The meteors of January on Titan, the largest satellite. M. Tisserand 1st-3d-called Quadrantids from the fact that includes in his discussion the motions of the their radiant is in Quadrans—were observed other satellites, and finds that the change in in unusual numbers by Prof. IIerschel at Hawkthe position of their orbits is not so much due hurst, England, on the morning of January 2, to the attraction of the ring as to that of the 1878. In thirty minutes Prof. Ilerschel counted protuberant matter about Saturn's equator. twenty meteors, of which seventeen were Quad1. Tisserand's value of the mass is cho, the rantids. Two were as bright as Jupiter, five mass of Saturn being 1. This is less than one equal to first-magnitude, six equal to second-, fifth of the value obtained by Bessel.
and the rest about equal to third-magnitude Comets.—The first comet of 1878 was dis
stars. covered by Mr. Lewis Swift of Rochester, N. Y.,
The Meteors of April 19th - 23d. — The on the 7th of July. It had a perceptible cen
"Monthly Notices” for May, 1878, give the tral condensation, but neither tail nor nucleus. results of Mr. W. F. Denning's watch for Its motion is direct; its inclination, 78 degrees; meteors of the April shower on the 20th, 21st, and its perihelion distance was 128,000,000 and 22d of the month. Twelve meteors were miles.
seen which belonged, undoubtedly, to the group The second comet of 1873 was detected on
of Lyraids. The radiant, very exactly deterits first predicted return by M. Tempel of Ar- mined, was in R. A. 272, N. decl. 32°? cetri, near Florence, on the 19th of July, 1878.
The August Veteors.—The meteors of AuIt had the appearance of a nebula three or gust 8th-12th were observed in 1878 under four minutes in diameter, with several nuclei.
unfavorable circumstances; cloudy weather in With the aid of Dr. Von Asten's ephemeris many places, as well as bright moonlight, inMr. John Tebbut of Windsor, New South Wales, terfering with the observations. In “The Obdetected Encke's comet on the evening of Au- servatory for September, Mr. II. Corder of gust 3d. This is the eighteenth perihelion pas- sults of his observations: During four hours
Chelmsford, England, gives the following resage since its periodicity was discovered by Encke, and the comet has been observed at
on the night of the 10th he counted 113 meeach successive return. Its appearance in 1878 teors, of which 97 wero Perseids. Of these, was that of an extremely faint nebulosity. Mr. 60 had visible streaks and 20 were colored J. I). Ilirst, writing from Sydney, New South The maximum was from 2n. 15m. to 3h 15m, Wales, under date of August 21st, says:
during which hour he saw 44 meteors. The
radiant was in R. A. 13°, N. decl. 56o. One The comet is a very inconspicuous object, even meteor was seen absolutely stationary at R. A. with a low power and the full aperture of tho 11:- 47°, N. decl. 58o. On the same night Mr. W. inch Sydney refractor. It appears as a circular nebulous body, showing signs of condonsation in the F. Denning, watching at Bristol, England, saw center, but no distinct nucleus. On the evening of 130 meteors in four hours and a half. During the 20th of August two tenth-magnitudo stars wero the half hour ending at 3 o'clock, when the observed in the field with the comet, the motion of tho Intter rendering it apparent that it must pass
moon had set, he counted 3:3. very close to, if not immediately over, one of them.
Veteoric Fire-balls.-In “The Observatory" This actually took plnoo just before the comet set, for February and March, 1878, Capt. G. L. the center of the comet passing directly over thó Tupman discusses the observations of a great
fire-ball seen in England, Ireland, and Wales, third that of the moon. The same fire-ball on the evening of November 23, 1877, at gh. was seen at Everett, Mass., by Mr. William F. 21"., G. M. T. The radiant of this meteor was Delany. in R. A. 62°, N. decl. 21° ; height when first A daylight meteor was seen in full sunshine seen, 96 miles; first explosion at mid-course, near Hlawick, England, by Mr. James Elliott exactly over Liverpool, at a height of 46 miles; and others, at 105. 20m. on the morning of March length of visible path, 133 miles ; time of flight, 25th. 8 seconds nearly ; velocity, 174 miles per sec A large detonating fire-ball was observed at ond; final explosion over the Irish Sea, at an several points in England on the evening of elevation of 14 miles. A bright streak 40 miles April 2d, at 7h. 55". It appeared in Ursa Main length and nearly half a mile in diameter jor, passed between Sirius and the belt of remained visible for several seconds over the Orion, and thence at a slow rate and in a dilatter part of the path. “All that was left after rect line to the horizon. Its diameter was the explosion settled slowly downward, perhaps about half that of the moon. for a mile, before becoming invisible, which A meteor whose apparent magnitude was would indicate that it was of the nature of an estimated at one third that of the moon was inpalpable powder.” The plane of the meteor's seen at Pultney, England, by Mr. James L. motion was nearly coincident with that of the McCance, on the evening of April 20th. In ecliptic. Capt. Tupman remarks that this fire- about two seconds it moved froin R. A. 42°, ball undoubtedly belonged to a meteor stream N. decl. 30°, to R. A. 47°, N. decl. 20°. previously known, whose radiant is in Taurus, A very bright meteor was observed by Mr. and that the orbit'is near that of the comet of Trouvelot of Cambridge, Mass., on the evening 1702.
of June 6th, at gh. 25m. It occulted Omicron The disappearance of the meteor was fol- Ursæ Majoris, and moved nearly due west. lowed by the most violent detonation. “The When about the middle point of its visible explosion of a 13-inch bomb-shell, consisting path it burst into several parts, but the exploof some 200 pounds of iron, would not have sion was followed by no detonation. produced a sound of one hundredth part of the On the evening of August 22d, at 10h. 2m, a intensity of the meteor explosion. This proves brilliant meteor was simultaneously seen by that it was of considerable mass compared to Mr. Seth O. Chandler, Jr., at Marlboro, N. H., an ordinary shell. A difficult question remains and Mr. E. F. Sawyer, at Cambridge, Mass. to be answered. IIow is it conceivable that At 7 o'clock P. M., November 12, 1878, a such a mass of heavy matter can be reduced to very brilliant meteor was seen in southern impalpable powder in five or six seconds ? All Indiana. Prof. D. E. Hunter of Washington, these bodies must be heavy to retain their Davies County, describes it as presenting a planetary velocities after impact with the at- clearly defined disk with a diameter equal to quosphere in the way they do.”
two thirds that of the full moon. It appeared Several other large meteors were seen on in Lyra, very close to Vega, passed in a souththe same evening, their paths, or at least some erly direction through the Milky Way, and disof them, radiating froin the same point in the appeared about 20° N. W. of Jupiter. It was constellation Taurus. Capt. Tupinan thus con visible ten seconds. cludes his interesting paper :
Binary Stars.—In Christie's “ Observatory The frequency of large detonating meteors about
for August and the following months Dr. November 21st-23d was long ago pointed out by Mr. Doberck of Markree, Ireland, has a valuable R. P. Greg and Prot. A. s. Ilerschel, but the exact memoir on binary stars. The following are determination of the radiant point or of their real his latest determinations of the periods of sevheights has seldom been possible. It is satisfactory enteen systems, together with the true eccento have secured one of them so well. From the in- tricities of their orbits: vestigations of Prof. II. A. Newton of Yale University, the great detonating meteor of November 20, 1877, in the United States, proceeded from the radiant near Gamina Cassiopeixe, found by Prof. Herschel for a detonuting meteor on the samé night in 1864. It is evident, therefore, that there are two streams, perfectly distinct, crossing the earth's orbit in the place it occupies about November 20th-230, and both Omega Lconis. gielding very large detonatiug meteors.
p Eridani.. In "Nature" for February 28, 1878, Mr. II. Tau Ophiuchi.. Hatfield describes a meteor seen by himself on Eta Cassiopeia
0.5678 the inorning of February 18th, at 126. 47o. Its
Lambda Ophiuchi. brilliancy surpassed that of the moon then 1938 Struve. full.
In the “Science Observer” for April, Mr. Sigma Coronxe. E.. F. Sawyer describes a meteor observed at Alpha Gominorum. Boston on the 31st of March, at 7. 54m.. It moved very slowly over an arc of eight de The average eccentricity of the binaries grees, and its apparent diameter was one whose periods are less than 200 years is
0.2600 0.8500 0:0768 04612 0:3510 0.3750) 0.6600 0.0091 0.6055
0.7930 0.7100 0.5974 0.6537 0.7390 0.7515 0.3292
9 16 21 47 19
124 2:2 23 377
0:4306; of those whose periods exceed 200 It is seen at a glance that the number of rea
stars increases with the length of the period, Ver Double Stars.—A new companion of while that of white or colorless stars deAldebaran has been discovered by Mr. S. W. creases. Burnham of Chicago, at the distance of only The stars are next classified according to 30" from the large star. It is very faint, be- their colors, and the average period of each ing about equal in apparent magnitude to the class computed. The result is shown in the outer satellite of Mars. In February, 1878, tablo below: the same distinguished observer discovered the companion of Rigel to be undoubtedly
Average period. double. The instrument used in his observa
126 days tions was the 181-inch Clark equatorial of the Chicago Observatory. Mr. Burnham calls at
Yellow-red tention also to the star 99 Ilerculis, whose duplicity was discovered by Mr. Alvan Clark in 1859. The companion, since the date of its “The progressive increase in the value of the discovery, has undergono a change of 42° in its average period from the white stars at the one angular position. The components, therefore, end of the scale to the intense red at the other in all probability, constitute a binary system. end is very remarkable.”
Birmingham on Red Stars.—Mr. Birmingham The Origin of Vebula.-The “Philosophical of England has been engaged for several years Magazine" for July, 1878, contains an article on the observations of red stars, and has re
on the origin of nebulæ by Dr. James Croll cently published some interesting results and of Scotland. Laplace and other writers on speculations in the Transactions of the Royal Cosmogony had assumed the existence of matIrish Academy.” Ilis cataloguo contains 658 ter in a state of gaseous diffusion, and had of these objects, with descriptions by himself shown how the solar and sidereal systems or references to the observations of other as
may have been formed by the process of contronomers. According to Mr. Birmingham, densation, and how future systems may be red stars are to be found chiefly in a partici- evolved in like manner from existing nebula; lar part of the heavens, viz., that part of the but what the previous condition of a nebula Milky Way extending through the constella was, or what physical cause had produced its tions Aquila, Lyra, and Cygnus. It is noticed, present gaseous state, they had never inquired. moreover, that a large proportion of the red The object of Dr. ('roll's memoir is “to exstars are variable, and that the intensity of amine the bearings of the modern science of their color varies inversely with the apparent energy on the question of the origin of nebumagnitude. Mr. Birmingham refers these lie, and in particular to consider the physical phenomena to the existence of nebulous rings cause of the dispersion of matter into stellar with an accumulation of matter on one side, space in the nebular form.”. and more or less absorption of some of the A brief view of Dr. (roll's hypothesis may colored rays, according to the densities of the be presented as follows: The so-called fixed different sections. color of the red stars stars are well known to have a proper motion which are not variable may be due, he sup- in space. Reasons are not wanting for beposes, to a permanent atmosphere. Ir. Bir- lieving that non-luminous bodies alsó exist, in mingham's memoir contains a collection and indefinite numbers, moving in all possible didiscussion of the spectroscopic observations of rections, and with various degrees of velocity. Iluggins, Secchi, Vogel, and 1)’Arrest.
The occasional impact of these opaque stars Relation between the Colors and Periods of would be a necessary consequence. With great Variable Stars.—The “Scienco Observer” for velocity at the moment of collision, sutlicient July, 1878, contains a paper by Mr. Seth ('. heat might be developed to reduce the united Chandler of Boston on the relation between
mass to the form of a gaseous nebula. Such the colors of variable stars and the lengths of is supposed to have been the origin of the their periods. In Schönfeld's catalogue of 138 thousands of nebule revealed by the telescope. variable stars he finds 26 whose colors are not The fixed stars have been produced by the given, or whose periods aro irregular. De- condensation of ancient nebula. These as they ducting these, ho arranges the remaining 112 cool down must gradually become extinct, to in classes according to the length of their continue their motion as non-luminous bodies periods, separating tho red or reddish from until a new encounter, in the distant future, those noted as white, yellow, or of no decided shall reconvert them into nebula. color. The result is as follows:
The process by which opaque stars are supWhite or yellow.
posed to have been transformed into nebulæ is thus given in Dr. Croll's very interesting me
moir : Under 100 days..
Take the case of the origin of the nebulous mass
out of which our sun is believed to have been formed. Over 100
Suppose two bedies, each one half the mass of the sun, approaching each other directly at the rate of
Red or roddish.
100_210 200-300 300-100
No. Per cent.
No. Per cent.
476 miles per second (and there is nothing at all im- explosion, however, would be to disperse the blocks probable in such a supposition), their collision would in all directions, radiating from the center of the transform the whole of the inotion into heat, afford mass. Those toward the outer circumference of the ing an annount sufficient to supply the present rate mass, meeting with little or no obstruction to their of radiation for 50,000,000 years. . Each pound of the outward progress, would pass outward into space to mass would, by the stoppage of the motion, possess indefinite distances, leaving in this manner a free not less than 100,000,000,000 foot-pounds of energy path for the layers of blocks behind them to foltransformed into 'heat, or as much heat as would low in their track. Thus eventually a space, persuffice to melt 90 tons of iron or raise 264,000 tons 1°haps twice or even thrice that included within the C. The whole mass would be converted'into an in orbit of Neptune, might be filled with fragments by candescent gas, with a temperature of which we can the time the whole had assumed the gaseous condiform no adequate conception. If we assume the spe- tion. It would be the suddenness and almost incific heat of the gaseous mass to be equal to that of stantaneity with which the mass would receive the air (viz., -2374), the mass would have a temperature entire store of energy, before it had time even to of about 300,000,000° C., or more than 140,000 times assume the molten, far less the gaseous condition, that of the voltaic arc. It may be objected that, which would lead to such fearful explosions and disenormous as would be such a teinperature, it would persion of the materials. If the heat had been gradnevertheless be insufficient to expand the mass ually applied, no explosions, and consequently no against gravity so as to occupy the entire space in- dispersion, of the materials would have taken place. cluded within the orbit of Neptune. To this objec- There would first have been a gradual melting; and tion it might be replied that, if the temperature in then the mass would pass by slow degrees into vaquestion were not sufficient to produce the required por, after which the vapor would rise in temperature expansion, it might readily have been so if the two as the heat continued until it became possessed of bodies before encounter be assumed to possess a the entire amount. But the space thus occupied by higher velocity, which of course might have been the gaseous mass would necessarily be very much the case.
But without making any such assumption, smaller than in the case we have been considering, the necessary expansion of the mass can be accounted where the shattered uraterials were first dispersed for on very simple principles. It follows in fact from into space before the gaseous condition was asthe theory that the expansion of the gascous m:-$ sumed. must have been far greater than could have resulted simply from the temperature produced by the con Researches of Prof. Chase.—Recent volumes cussion. This will be abrious by considering what of the “ Proceedings of the American Philomust take place in inediately after the encounter of the two bodies, and before the mass has had suffi
sophical Society contain papers of great cient time to pass completely into the gaseous con- interest by Prof. Pliny E. Chase of Ilaverford dition. The two bodies coming into collision with College, Pa., on “ Centers of Aggregation and such enormous velocities would not rebound like Dissociation,” “Illustrations of Central Force,” two elastic balls, neither would they instantly be
“Results of Wave Interferences, ? " Criteria of converted into vapor by the encounter. The first effect of the blow would be to shiver them into frag- the Nebular Hypothesis," “ Radiation and Roments, small indeed as compared with the size of tation," etc., etc. The numerous harmonies the bodies themselves, but still into what might be of the solar system pointed out in these papers called in ordinary language immense blocks. Before the motion of the two bodies could be stopped attention of astronomers and physicists.
are very remarkable, and must command the they would undoubtedly interpenetrate each other; and this of course would break them up into fray Gold Medal of the Royal Astronomical Soci
But this would only be the work of a few ety.—The gold medal of the Royal Astronomiminutes. llere, then, we should have all the energy cal Society of London was awarded in 1878 of the lost inotivn existing these blocks as heat (molecular motion), while they were still in the solid
to Baron Dembowsky of Gallarate, for his obstate ; for as yet they would not have had sufficient servations of double stars, communicated from time to assume the guseous condition. It is obvious, time to time during the last quarter of a cenhowever, that the greater part of the heat would ex- tury to the “ Astronomische Nachrichten.'' ist on the surface of the blocks (the place receiving
Prizes of the French Academy of Sciences.the greatest concussion), and would continue there while the blocks retained their solid condition. It The prizes of the French Academy, in the secis difficult in imagination to realize what the tem tion of Astronomy, have been awarded as folperature of the surfaces would be at this moment. lows: the Lalande prize to Prof. Asaph Hall For, supposing the heat wero uniformly distributed of Washington, for his discovery of the satelthrough the entire mass, each pound, as we have lites of Mars; the Vaillant prize to Dr. Schulhof, already seen, would possess 100,000,000,000 footpounds of heat. But as the greater part of the heat for his researches which led to the rediscovery would at this instant be concentrated on the outer of three of the lost asteroids; and the Valz layers of tho blocks, these layers would be at once prize to the brothers Paul and Prosper Fenry transformed into the gaseous condition, thus envelope of the Paris Observatory, for their continuation ing the blocks and filling the interspaces. The temperature of the incandescent gas, owing to this enor
of Chacornac's ecliptic charts. mous concentration of heat, would be excessive, and
Gold Jellal of the l'ienna Academy of Sciits expansive force inconceivably great. As a con ences. The gold medal of the Vienna Academy sequence, the blocks would be separated from each has been awarded to Mr. Lewis Swift of Rochother, and driven in all directions with a velocity ester, N. Y., for his discovery of the first comet far more than sufficient to carry them to an infinite of 1878. The observations of Mr. Swift have distance against the force of gravity were no opposing obstacle in their way. The blocks by their mu- hitherto been made under unfavorable circumtual impact would he shivered into smaller frag- stances. Ile now proposes, however, the immonts, each of which would consequently becomo mediate erection of an observatory, to be furenveloped in incandescent gas. These smaller frag; nished with a 9.4-inch refractor by Messrs. ments would in a similar manner break up into still sinaller pieces, and so on until the whole came to Clark & Sons, the distinguished opticians of assume the gaseous state. The general effect
of the Cambridgeport, Massachusetts.