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graphs, taken with 14 telescopes or cameras and uncorrected for photography. The volume con8 spectroscopes, one of the telescopes being of tains also a careful study by Prof. Holden of 13-inches aperture, the largest ever used in Barnard's photographs and of all the photoobserving a total eclipse of the sun. Through graphs and sketches transmitted to Lick Obser

vatory. We quote briefly Prof. Holden's conclusions, which may be regarded as representing the results from this eclipse as far as they are at present attainable :

I. That the characteristic coronal forms seem to vary periodically as the sun spots (and auroras) vary in frequency, and that the coronas of 1867, 1878, and 1889 are of the same strongly marked type, which corresponds, therefore, to an epoch of minimum solar activity.

II. That so-called “polar” rays exist at all latitudes on the sun's surface, and are better seen at the poles of the sun, simply because they are there projected against the dark background of the sky, and not against the equatorial extensions of the outer corona. There appears to be also a second kind of rays or beams that are connected with the wing-like extensions. These latter are parts of the “groups of synclinal structure” of Mr. Ranyard.

III. The outer corona of 1889 terminated in branching forms. These branching forms of the outer corona suggest the presence of streams of meteorites near the sun, which, by their reflected light and by

their native brilliancy, due to the collisions of their ECLIPSE OF THE SUN, JANUARY 1, 1889.

individual members, may account for the phenomena

of the outer corona. the kindness of Prof. Pickering, we are able to corona along and very near the plane of the ecliptic

IV. The disposition of the extensions of the outer reproduce a photograph taken

with this

instru- might seem to show that, if the streanis of meteorites ment, which shows wonderfully well the fila- above referred to really exist, they have long been inmentous structure of the corona.

tegral parts of the solar system. A party from Lick Observatory, under Mr. NOTE.-The conclusions III and IV appear to be Keeler, was at Bartlett Springs; one from Wash- contradictory to that expressed in I. The electrical ington University Observatory, St. Louis, under theory announced by Dr. Huggins in the Bakerian Prof. Henry S. Pritchett, at Norman; one from lecture for 1885 seems to reconcile the conclusions I, Carleton College, at Chico; and many other III, and IV. available points were occupied by individual taken just before contact II and just after contact III

V. The photographs of the corona which were astronomers or photographers. At Cloverdale, prove the corona to be a solar "appendage, and are the Pacific Coast Amateur Photographic Associ- fatal to the theory that any large part of the coronal ation was represented by thirty cameras.

forms are produced by diffraction.. A report from Lick Observatory, containing VI. The spectroscopic observations of Mr. Keeler the observations of the Lick party at Bartlett show conclusively that the length of a coronal line is Springs, and also reports from many co-opera- coronal atmosphere of the sun at that point, and

not always an indication of the depth of the gaseous tors all over the State, including those from the hence to indicate the important conclusion that the Amateur Photographic Association, has been true atmosphere of the sun may be comparatively published with characteristic promptness by shallow. Prof. Edward S. Holden. The Smithsonian In VII. Mr. Keeler draws the further conclusion in his stitution has published a series of photographs report : : . that the “polar” rays are due to beams of the corona on a uniform scale, copied from a of light from brighter areas of the sun illuminating collection of positives on glass kindly presented the suspended particles of the sun's gaseous envelopes

.

In order that this conclusion may stand, it is necesby various observers, and has also published a

sary to show that all these “polar" beams are comsuggestive paper by Prof. Frank Bigelow, posed of rectilinear rays. . . . An important concluwherein he traces a close agreement betweension from (the photographic and photometric) measmagnetic lines of force computed for the sun, ures seems to be that it is impracticable to photograph and the curves of the polar filaments shown the corona in full sunshine with our present plates, upon the Pickering photograph. The detailed and that a photographic search for Vulcan is hopeless. report of the Harvard party has not yet ap The Sun.-H. Crew, whose observations of peared. Prof. H. A. Howe, of Chamberlin Ob- the rotation of the sun were noted in last year's servatory, at Denver, describes his own observa- summary, has recently made a new series of obtions and those of his co-operators at Win- servations for the correction or confirmation of nemucca, Nev., as the initial publication of his the conclusion that the angular velocity of rotanew observatory, and many preliminary reports tion increases with an increase of latitude. He are contained in current journals. The frontis- still finds shorter rotation periods for the higher piece of Lick Observatory report is an admirable latitudes, the mean value for the period at latiphotograph of the corona by Barnard, which tude 45° being eighteen hours shorter than at seems to compare favorably with Pickering's, the equator, but, owing to the smallness of this though one was taken with an object-glass of difference and to the uncertainty of the observa13-inches aperture specially made for the pur- tions, he is of the opinion that "no certain variapose, and the other with a little telescope of 31. tion of period with latitude has been detected inches aperture stopped down to 14 inch and with the spectroscope.” Attention is called,

[graphic]

however, to the wide differences of the equato- white spot on the rings of Saturn adjacent to rial period as obtained by different methods--dif- the shadow of the ball and similar to the white ferences that may be due to the fact that we are spots sometimes seen upon Jupiter. On the 12th really dealing with different strata of the sun, it was again seen with an eight-inch Grubb telthough here, also, too much reliance must not be escope, but it was invisible on the 13th, 20th, placed upon the observations.

22d, and 23d, and on April 2. Evidence as to During 1888 sun-spots were few, small, and in the real existence of this spot is extremely conlow latitudes, and there were frequent intervals tradictory. Several observers have confirmed in which no spots at all were seen—longer inter- Dr. Terby's discovery, but Mr. Common was unvals, in fact, than any since the minimum of able to see the spot with his five-foot reflector, 1879. The most prolific month as to entire nor could it be seen with the great Lick telespotted area, though not as to number of spots, scope. Prof. Hall is inclined to believe that the was November, following immediately a long phenomenon is an effect of contrast. The very period of quiescence. There was a rough tend- fine division on the outer ring of Saturn, detectency of spots to certain solar longitudes; and ined with the thirty-six-inch Lick refractor early latitude they continued to be more numerous in in 1888, was again seen in 1889, at a distance of the southern than in the northern hemisphere. about one sixth of the breadth of ring A from Faculæ did not vary simultaneously with spots, its outer edge. A dark shading extended inward but their diminution as compared with 1886 and from the new division almost to the inner edge 1887 was slight. They showed a very noticeable of the ring. Prof. Holden has also noted an exdevelopment during the secondary maximum of tremely narrow, brighter polar cap, about five September, while the prominences fell off consid- seconds wide, in a direction parallel to the equaerably both in September and November, but at- tor and perpendicular to this, about the width of tained their greatest development in March and the Cassini division at the ansæ. Asaph Hall, April.

Jr., has found from his observations of Titan a Planetary Tables.-An important and la- value for the mass of Saturn of 1 : 3,500-5, the borious work is being carried on by Prof. Si- sun's mass being unity. This is in close agreemon Newcomb, consisting of the redetermination ment with Bessel's revised value, 1:3,502:5, and of the elements of all the large planets from Struve's, 1 : 3498. the best and most recent observations, and of Uranus.-At the July meeting of the Royal the construction of tables founded on uniform Astronomical Society, Mr. Tayler described cerdata. This involves an immense amount of com- tain observations of the spectrum of Uranus, putation, including the re-reduction of the older made with a direct-vision spectroscope attached planetary observations and the discussion of the to the five-foot reflector at Common's observalater ones, with a view of reducing them all to a tory, Ealing. Bright flutings were detected in uniform system. Another branch of this planet- the red, orange, and green, and also four dark ary work is a determination of the mass of Ju- bands in the orange, green, greenish-blue, and piter from the motions of Polyhymnia, and a blue, indicating that the planet is to some extent comparison of Hansen's tables of the moon, with self-luminous. No solar lines were seen. But observed occultations since 1750.

Dr. William Huggins, by help of photography, In commenting upon recent determinations of has found evidence of their existence. With an planetary masses from the motions of comets, exposure of two hours, on June 3, 1889, he obProf. Hall says: “ The objection to deducing tained a spectrum in which all the principal solar values of planetary masses from the motions of lines were distinctly seen, but he was unable to comets consists, I think, in the fact that appar- distinguish any other lines, bright or dark. ently other forces than that of gravitation act Neptune.--Observations of the satellite of on these bodies. As a comet approaches the Neptune during the past three years have shown sun it changes form, disintegrates, and matter is that the plane of its orbit undergoes considerthrown off to form a tail. Until we know more able perturbations hitherto unexplained. Prof. of the theory of these changes, the computation Newcomb and M. F. Tisserand have, independof masses from the motions of comets and infer- ently, suggested that this may be accounted for ences about the resisting medium in space must by supposing that Neptune is slightly flattened, be uncertain."

and that the orbit of the satellite makes an angle The Earth.-M. A. Ricco has called attention with the equator. to a phenomenon that gives a striking proof of Asteroids.-Following is a table of the astethe rotundity of the earth, though it has hardly roids added to the list since Oct. 25, 1888: been noticed hitherto. At the Observatory of Palermo, which is 14 miles from the Mediterranean Sea and 236-2 feet above its level, a great num

Discoverer. ber of photographs of the sun, reflected from the surface of the water, have been taken a few min- 280. Philia. Palisa, at Vienna. utes after rising or before setting, and they show 281. Lucretia Palisa, at Vienna.

Charlois, at Nice

1889 Jan. 28. that the diameter in the plane of reflection is

Charlois, at Nice less in the reflected image than in the direct. 284.

Charlois, at Nice

May 29. This deformity is due to the fact that the sur

Charlois, at Nice

Ang. 3. face of the water forms a cylindrical mirror. 287. Nephthys... Peters, at Clinton. 48

Palisa, at Vienna,

Aug. 8.

Aug. 25. with axis horizontal and normal to the plane of reflection; the amount of the observed flatten Number 277 has received the name Elvira, ing accords well with that demanded by theory. and 279 the name Thule. An asteroid of the

Saturn.-Dr. F. Terby, of Louvain, reported, twelfth magnitude, picked up by Palisa on Jan. on the evening of March 6, 1889, discovery of a 4, 1889, proved to be Siwa, 140.

No.

Name.

Discov

erer's numb'r.

Date of disenvery.

67
68

18SS Oct. 29.

Oct. 81.

282. 283.

Feb. 8.

285.
286.

69

Comets.— The origin of comets, always a fruit- maining visible for several months longer. Barful field for speculation, has received more than nard remarked, on June 3 that there was an anomusual attention of late. Dr. Th. Bredichin has alous tail directly following the comet about, expressed the opinion that periodic comets owe 1° in length and some 2 or 3' broad. There their origin to the segmentation of ordinary par was no trace of a tail preceding or pointing away abolic comets, having been thrown off from the from the sun, the direction usually taken by these latter by an eruption, such as we have probably cometary appendages. The spectrum on Nov. 14, witnessed in the great comet of 1882 and in Biela's according to Dr. Ralph Copeland, instead of becomet. A valuable paper on the capture theory ing composed of the usual feeble, separate bands, of comets by M. Tisserand will be found in the was continuous, brighter in the middle, and fad* Bulletin Astronomique" for June and July, ed gradually at both ends; it resembled the spec1889. In a recent paper by Dr. J. Holetschek it trum of a close globular star-cluster or of a nonis claimed that the apparent systematic grouping gaseous nebula, rather than that of a self lumiof cometary perihelia in certain directions (2700 nous gas. Faint patches of light were made out and 90° of heliocentric longitude) has no connec- in the positions usually occupied by the second tion with the general motion of the solar system, and third cometary bands. Similar observations but is due to the position of the earth at the were made later, and on Dec. 8 all three bands time that these discoveries are most readily made. were distinctly visible, but on each occasion the

Among the most important of recent contri- continuous spectrum formed the ground on butions to cometary literature is Dr. H. Kreutz's which the brighter spectrum was superposed. monograph on the great September comet 1882 Dr. Copeland says, “It seems probable that the II, the comet that was seen in full daylight, and comet shines mainly by reflected light, ... to was followed by astronomers until it actually which the action of the sun on the cometary madisappeared against the sun's disk. The formi- terial is slowly adding the usual bright bands." dable obstacles to an accurate determination of Comet 1889 II. On the evening of March 31, the orbit, presented by the disintegration of the E. E. Barnard discovered, with the 12-inch equanucleus into several points of condensation, seems torial of Lick Observatory, a very small and exto have been most skillfully surmounted by the tremely slender comet, the head being not over computer. The final value for the period is 772-2 10" in diameter and the tail about 15' in length; years. Dr. Kreutz has also finished a computa- the nucleus was stellar and of about the thirtion of the orbit of comet 1880 I, but its publi- teenth magnitude. cation is delayed until the completion of Dr. Comet 1889 III. Mr. Barnard discovered, with Weiss's determination of that of 1843 I, as these the 64-inch equatorial of Lick Observatory, anthree comets seem to belong to the same come- other faint comet, at about 2 o'clock on the morntary system, distinguished for short perihelioning of June 24, in the constellation Andromeda. distances; and we, no doubt,

now have

a fourth According to elements computed by W. W. Campmember of the same family in the headless com- bell, it had passed perihelion on June 20, and was et 1887 I.

receding from the earth as well as from the sun William R. Brooks, of Geneva, N. Y., reported when discovered. The last observation seems to the discovery, on the morning of Jan. 15, 1889, have been obtained at Lick Observatory on Aug. 6. of a faint comet in the constellation Sagittarius. Comet 1889 IV. A tolerably bright comet was This comet, to which the designation Comet a, discovered in Centaurus by Davidson at the 1889, was given, in order to distinguish it as the Melbourne Observatory on July 21. On the 25th first comet discovered in the year was diligently it was easily visible to the naked eye, and in a searched for by several observers, especially by small telescope showed a bushy tail. A photoBarnard and Swift, who examined the region graph of this comet was secured on July 30 at carefully from Jan. 19 to Feb. 13, but without Lick Observatory by Mr. Barnard. The time success. As the three observations necessary for of exposure was one hour and thirty minutes, determining the orbit were not secured, this com- and the negative showed a wide, fan-shaped tail, et is not catalogued among the comets of the with borders concave to its axis and pretty bright year. A comet announced by Swift on July 15, for 20' from the head and traceable to 53'. Prof. is also omitted, as it proved to be identical with Holden finds that the brightest part of the tail the comet discovered by Brooks on Aug. 7, 1888 was sooo of the brightness of the brighest part (1888 III). The comets of 1889 (up to the end of of the solar corona on Jan. 1, 1889, and goodood October), arranged in the order in which they that of the full moon. passed perihelion, are then as follows:

Comet 1889 V. William R. Brooks, while sweepComet 1889 I or Comet e 1888, designated as ing the southwestern heavens with a 108-inch Comet V in the record of last year, was discovered equatorial on the morning of July 6, discovered by Barnard, at Lick Observatory, with a 4-inch a suspicious-looking nebulous object, the cometcomet seeker on Sept. 2, 1888, or the morning of ary character of which he was able to confirm Sept. 3, and was also independently discovered by observations on the following morning. The by Brooks at Geneva on the following morning. position at the time of discovery was right asIt was a round, nebulous mass, l' in diameter, with cension 23h 45m, declination -9° 10'. It was a central condensation of between the eleventh then faint, with a short, wide tail. The comet and twelfth magnitude and no tail. At the end attracted no special attention on the part of asof November and beginning of December, it was tronomers till Aug. 1. when Barnard discovered visible to the naked eye and about as bright as a that it had apparently given birth to two small star of the sixth magnitude. Perihelion was nebulous bodies. The next morning showed passed on Jan. 31, 1889, and by the end of Feb- that both objects, which he designated as B and ruary it disappeared in the sun's rays, reappear. C, were moving with the parent comet through ing, however, about the middle of April, and re- space. Mr. Barnard says: “ On Aug. 3 they were

examined with the 36-inch equatorial, which Star-Catalognes. Dr. Auwers published in showed the whole group very beautifully. Each 1880 a provisional list of 303 reference stars for of the companions had a very small nucleus and the southern zones of the Astronomische Gesellcondensation in a very small head and a short, schaft between - 2o and — 23°, and although the faint tail, presenting a perfect miniature of the material accumulated since that time is not suffilarger one, which was pretty bright and well de- cient to give the most accurate places, he has preveloped, with small nucleus and slightly fan- pared a catalogue of positions which will probabshaped tail o long. There was then absolutely ly require but slight correction. The places have no nebulous connection with the larger, nor has been reduced to 1885 by carefully determined there been at any time since, either in the 12-inch proper motions. or in the 36-inch telescopes. Nothing whatever A collection of all available meridian obserhas been seen here of the nebulous envelope vations of stars that will be within 1° of the spoken of by the Vienna observers as apparently north pole in 1900 has been prepared by Miss inclosing the whole group (A. N., 2,914). Í Anna Winlock, and published as No. 9, of vol. have from the first carefully looked for a nebu- xviii, of the “ Harvard Observatory Annals." lous connection. Under unfavorable circum- Prof. Safford has published a catalogue of right stances the tails of B and C might be imagined ascensions of 261 stars, mostly within 10° of the to be a connecting nebulosity, but the tail of B pole, observed with the 44-inch Repsold meridian falls short of A, and that of C does not nearly circle of Field Memorial Observatory at Willreach B. Each comet is in appearance absolute- iamstown from 1882 to 1887. ly independent of the other. The tails of all The third volume of Auwers's new reduction three have lain in the line of the nucleus of A, of Bradley, which has been five years in going and therefore have not sensibly deviated from through the press, was finally published in 1888. the position-angle 241°.

This volume contains, in addition to the cata"On Aug. 4 two other companions were detected logue proper, tables giving the quantities in the with the great telescope, one of which was meas- reduction to the apparent place that depend ured, the other being too elusive to set the wires upon the star's position, and a comparison of on. I have numbered these four companions B, Bradley's positions, reduced to 1865, with Berlin C, D, E, in the order of increasing right ascen- and Greenwich observations of about the same sion, A being the larger comet, D and E being date. The catalogue contains 3,268 stars. the two last discovered. D has been seen several Star Charts.-A series of charts embracing times since the moon withdrew, but has always all the stars visible to the naked eye—that is, been too faint to observe; it has not sensibly down to about the six-and-a-half magnitude changed its position. E has only been seen once; has been published by Mr. Cottam, and has its position-angle referred to C would be the been highly complimented. There are thirtysame as that of D, and its distance twice as great. six sheets, the scale being one third of an inch Four or five other nebulous bodies observed near to one degree of a great circle. Another most the comet Aug. 2 have not since been seen, and useful set of star maps is Klein's new star atlas, were probably nebulous.

which has appeared in both English and Ger“The results of the observations of the two man editions. In the latter there are eighteen brighter companions are extremely interesting: maps, containing about the same number of stars Measures of B have been made on eighteen, and as Mr. Cottam's, and giving also all the nebulæ of C on seventeen nights. These two have and clusters visible in telescopes of moderate almost exactly the same position-angles, which power--a great help to comet hunters. have been sensibly constant; their distances Stellar Spectra.—The researches that confrom the main body have, however, been increas- stitute the Henry Draper Memorial, at Harvard ing. At the last observations, B seems to be Observatory, have consisted for the past three stationary, the distance from A remaining con- years in the photographic study of stellar specstant, while C continues to recede."

tra; and, while this will continue to be the prinAccording to elements published by Dr. Knopf, cipal subject for investigation, Mrs. Draper has the main comet passed its perihelion on Sept. 27 decided to extend the field of work undertaken so at a distance from the sun of 1.96 in terms of the as to include the study of other physical properearth's mean distance, and its period of revolu- ties of the stars by photography. The first retion is 7.286 years.

search is now rapidly approaching completion. Such resolution into several points of extreme The catalogue of spectra of bright stars as far condensation was well exemplified in the case of south as – 25o declination is practically ready the great comet of 1882, but there the separate for the printer; the photographs for the catacondensations were contiguous, and all were en- logue of the spectra of faint stars are nearly finveloped in one common nebulosity. But in the ished, and the detailed study of the spectra of the present case the two components were far apart, brighter stars by means of the 11-inch refractor, and each was surrounded by its own nebulosity, with one, two, or four large prisms over its oba phenomenon of which we also have a precedent ject-glass, will probably be completed within the in Biela's comet. This comet, which was dis- year. The 8-inch Bache telescope, with which covered in 1772, continued single till November, the observations for the first catalogue referred 1845, and then, by the end of December, sepa- to have been made, remained in California after rated into two distinct nebulosities. In 1852 the the New Year's eclipse until Feb. 2, 1889, and two companions were seen, but the distance had was then sent to Peru to continue work upon the increased eightfold, and at the next return they spectra of bright stars from - 25° to the south had apparently been dissipated in a shower of pole; the resulting photographs will be sent to meteors; diligent search has failed to reveal the Cambridge for reduction. The research on the least trace of the comet since.

spectra of faint stars will also be continued to

Annual

NO. OF STARS.

motion.

10

the south pole, and it is expected that this work Dr. J. A. C. Oudemans has collected, in the in the southern hemisphere will be completed in “ Astronomische Nachrichten," Nos. 2,915 and two years. The Bache telescope will be replaced 2,916, the scattered results for stellar parallax at Cambridge by an instrument of similar con- obtained in the past sixty years, in a very construction provided by Mrs. Draper.

venient form, with notes on authorities. The Photography has been applied very success- following table forms a summary of his paper : fully, by Dr. Vogel, of Potsdam, to the determination of the velocities of stars in the direction

Proper

Distance in of the line of sight from the observer to the star

parallax. light years. under observation. The displacement of the lines of the spectrum due to this motion of the

4.98" 0.32 star to or from the observer, or of the observer to or from the star, is extremely minute, and the accordance of the measurements made by Dr. 10 Vogel is quite remarkable. His mean results for the motion referred to the sun-that is, after the From which Dr. Oudemans concludes that observed motion has been corrected for the known "stars with proper motions greater than 05" motion of the earth in its orbit-are as follow: have probably an annual parallax of 10" to -50". Capella receding from the sun 16 miles a second.

9
9
9

2.83
1.00
0.88
0.05

0.20
0.20
0.18
0.16

16 16 18 20

Variable Stars.-Several important papers Aldebaran receding from the sun 80 miles a second. Polaris approaching the sun 16 miles a second.

by S. C. Chandler have been published in the Algol approaching the sun 7 miles a second.

"Astronomical Journal.” In one of these, Mr. Procyon approaching the sun 7 miles a second. Chandler describes an ingenious method of estiStellar Parallax.-Prof. Pritchard, of Ox- mating star colors, which he has used with good ford University Observatory, has continued his effect. It consists in estimating the relative investigations of stellar parallax by means of change of brightness effected in two stars by the photography, his aim being to examine all stars interposition, first of a blue and then of a red of the second magnitude suitably situated for shade-glass. If a red and a white star appear of observation at Oxford, in the hope of contribut- the same brightness when viewed directly, the ing somewhat to our knowledge of what Her- red star will seem the fainter when the blue schel called the “construction of the heavens.” glass is interposed, but the brighter with the With reference to the differences between the red glass. These differences of brightness can results obtained by different observers, Prof. be precisely estimated by Argelander's method, Pritchard says: "Guided by the suggestions of and they thus afford definite measures of the recent experience, I now think that such differ- differences in color of the two stars on an arences of parallax' might very reasonably have bitrary scale depending upon the glasses embeen anticipated, and may probably be accepted ployed. The effect of brightness upon the scale as matters of fact, without in any degree im- estimates seem to be imperceptible, at least pugning the accuracy of the observations. For between the second and ninth magnitudes. An in process of this work on parallax, and also important result of Mr. Chandler's investigafrom the general history of similar inquiries, it tions is the intimate connection shown between has been made abundantly evident that no neces the length of period and the depth of color of sary connection exists between the brightness of the star; the very short period variables are a star and its position in space or distance from nearly white; those of longer period somewhat the sun. Nevertheless, it is this very difference redder, the tint growing deeper the longer the of brightness mainly which guides us in the period. The possessors of large refractors are selection of comparison stars. The parallax' strongly urged to devote a portion of their time is, in fact, and is becoming more and more gen- to the observation of the minima of variables erally recognized to be, a differential quantity, that become too faint for ordinary telescopes, fainter stars being in very many instances much our knowledge of such variables being extremely nearer to us than others possessing incomparably deficient. Argelander's method of observation greater brightness. In passing, I may here in- is recommended. stance a Lyræ as compared with 61 Cygni; B Cen

Mr. Chandler has collected the observations of tauri as compared with e Indi. In fact, the posi- U Ophiuchi (of all variables, the one with shorttion in space of the faint comparison stars in est period and most rapid fluctuations of light), relation to that of the star whose parallax is and he finds a curious but well-marked retarsought is, if not a matter of accident, at all dation in the increase of brilliancy some half-hour events wholly unknown until the observations or so after minimum is passed. “A similar irregand computations are complete.".

ularity has been noticed in the light-curve of S Prof. Pritchard's final results for stellar paral- Cancri and occasionally in that of Algol. Further lax, as published in the third volume of the observations of the Algol variable Ý Cygni, the “Oxford Observations,” are as follows:

period of which has hitherto been uncertain, have

fixed this element at 1d 11h 56m 48s; the period Magnitude. Proper

of R Canis Majoris, an interesting variable de

tected by Mr. E. F. Sawyer, is undoubtedly very 611 Cygni

close to 1d 3h 15m 56s. 612 Cygni

An "Index to Observations of Variable Stars" # Cassiopeixe

forms No. 8 of vol. xviii of the “ Annals of the Polaris a ('assiopeia

Harvard Observatory.” A large number of unB Cassiopeia

published observations are referred to, particy Cassiopeix

ularly three extensive series of observations by a Cephei

Argelander, Heis, and Schmidt.
VOL. XXIX-4 A

STAR.

Parallax.

motion,

4.98
4.98
5.40
2.05

5.164
5.16
8.75
0.05
0.05
0.55
002
0.16

0.04
0.08
0.04
0.16
0.01
0.06

2.82
2.19
2.57

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