member of the Jovian family of satellites. The periodic comets discovered by Winnecke and Tempel in 1858 and 1873, respectively, reap peared, and three new comets were found. The death roll of the year included the names of Arthur Auwers, famous for his re-reduction of Bradley's observations and the compilation of star-catalogues; Lady Huggins, the able assistant of her distinguished husband, the late Sir William Huggins, in his epoch-making researches in astrophysics; G. F. Chambers, whose popular works on astronomy have been largely instrumental in spreading a general knowledge of the science; and Theodore Albrecht, chief of the International Bureau for the Investigation of Latitude Variation from its foundation in 1898.

MOUNT WILSON SOLAR OBSERVATORY. In his report of the work accomplished by himself and his assistants at this observatory during 1914, Prof. George E. Hale called attention to the fact that the opening of the second decade of the existence of the observatory was marked by a vigorous revival of solar activity after a prolonged period of calm. The first decade was remarkable for the amount of work accomplished and the new fields of inquiry in solar physics which were opened up. The skill of the director and his co-workers in devising new methods of research was unparalleled in the history of astronomical activity in this field, and it is not too much to say that, in quality, as well as quantity, of output, the observatory stood unrivaled among those devoted to the investigation of the physics of the sun. The methods which were developed and tested during the first decade became firmly established and gave promise of even greater and more important results for the future. The year 1914 was one of the most productive in the history of the observatory. The principal conclusions derived from the work of the year were summarized under 59 heads. Investigations were made of the general magnetic field of the sun, and of the magnetic fields of sun spots. In the case of the former, its existence was shown by 25 lines, representing the elements iron, chromium, vanadium, and nickel (with one unidentified), and all originating at comparatively low levels in the solar atmosphere. Attempts were made to observe the Stark effect due to electric fields in sun spots, but yielded no positive results. On "flash" spectra taken without an eclipse more than 1000 bright lines were measured, surpassing in number those photographed in the same region of the spectrum at eclipses and representing a lower level in the solar atmosphere. A preliminary study of the displacements of solar lines at the sun's centre gave no evidence of the gravitational shift toward the red predicted by Einstein, and the results also failed to support the anomalous dispersion theory advanced by Julius. From an investigation of the levels of the various elements in the sun's atmosphere, the conclusion was reached that the great mass of the vapors present is condensed in a very thin layer close to the photosphere.

The first determinations of stellar parallax with the 80-foot Cassegrain combination of the 60-inch reflector were completed and found very satisfactory. The enormous velocity in space of 577 kilometers per second was found in the

case of the star O.Arg.S.14320. By the measurement of some 600 stars near the North Pole, there was established for stars from the second to the twentieth magnitude a photographic scale, which agrees closely with the Harvard scale for the middle interval but shows divergencies for both bright and faint stars. The disappearance of the chief nebular_lines_from the spectra of Nova Auriga and Nova Persei was observed; these spectra are now identical with those of certain Wolf-Rayet stars, and it is suggested that the latter may be temporary stars in the later stages of their history. Work on the 100-inch mirror was steadily maintained, an almost perfectly spherical figure being obtained, and preparations for its parabolization were made, including the completion of the 60-inch plane mirror for testing its figure.

POLARITY OF SUN SPOTS. When the magnetic polarity of sun spots was discovered at Mount Wilson in 1907, it was expected that the spot vortices in the northern and southern hemispheres of the sun would have opposite directions of rotation. This expectation was not immediately realized, for spots showing opposite directions of rotation were soon observed in each hemisphere. Professor Hale's discovery of bipolar spots in 1909, however, afforded a basis for a reconsideration of the whole question, and it was found that, if every spot were classified as the preceding or following member of a bipolar group, as a rule the preceding (or following) spots in opposite hemispheres showed opposite polarities. Later work at Mount Wilson on the polarity of sun spots brought out the interesting fact that, while in the new spot cycle just begun the rule of opposite polarity for the preceding (or following) spots in the two hemispheres still holds, the polarities in a given hemisphere are opposite to those observed in that hemisphere just before the recent spot minimum. in accordance with the well-known law of sun spot distribution, the spots of a cycle appear at first in high solar latitudes and descend as the cycle progresses, it seems likely that the polarity is determined by the solar latitude, and it is suggested that the simplest explanation of the anomaly lies in assuming the existence of high and low latitude zones, distinguished by spots of opposite polarity. Future observations are expected to test this view, and also to reveal what happens in the intermediate

zone.

Since,

SOLAR RADIATION CONSTANT. In spite of the extremely accordant values of the solar radiation constant obtained by Messrs. Abbot, Fowle, and Aldrich, of the Smithsonian Institution, from measurements made under diverse conditions of height above sea level, atmospheric transparency, temperature, etc., their results were severely criticized. It was urged by some that their allowance for the heat absorbed by the atmosphere was too low; by others it was claimed that the amount of solar radiation reflected from the outside of the atmosphere was underestimated, and that the true value of the constant should be at least 3, and perhaps as high as 4 calories per square centimeter per minute instead of 1.93 calories, the value deduced by the Smithsonian observers. This value was derived from nearly 1000 measurements made during the period 1903-1914 at

expenditures for the support of schools was $4,470,936.

CHARITIES AND CORRECTIONS. The charitable and correctional institutions of the State under the control of the State Board are the State Hospital for Nervous Diseases at Little Rock, Deaf Mute Institute at Little Rock, School for the Blind at Little Rock, the Confederate Soldiers' Home at Sweet Home, Arkansas State Penitentiary and State Farm, and the Arkansas State Reform School at Little Rock.

POLITICS AND GOVERNMENT. The Legislature met in 1915, and passed several measures of importance. The first of these related to the matter of liquor regulation. A State-wide prohibition bill known as the Newberry Bill passed the House of Representatives on February 1. This measure prohibits the sale or giving away of liquor after June 1, 1915. It made a violation of the law a felony, and provided for prison terms of not less than one year. The Senate adopted the bill with an amendment that it be come effective on July 1, 1915. It was signed by Governor Hays. The Senate on February 1 passed a resolution referring a constitutional amendment providing for woman suffrage to popular vote. On account of the provision of the State Constitution which provides for the submission of not more than three proposed amendments to the Constitution at any election, it was necessary to defer the settlement of the question for two years.

STATE OFFICERS. Governor, George W. Hays; Secretary of State, Earle W. Hodges; Auditor, M. F. Dickenson; Treasurer, Rufus G. McDaniel; Attorney-General, Wallace Davis; Commissioner of State Lands, Highways, and Improvements, William B. Owen; Commissioner of Mines, Manufacture, and Agriculture, John H. Page; Superintendent of Public Instruction, George B. Cook.

SUPREME COURT. Chief Justice, E. A. McCulloch; Associate Justices, Carroll D. Wood, J. C. Hart, W. F. Kirby, and Frank Smith. STATE LEGISLATURE.

ARKANSAS, UNIVERSITY OF. A State in stitution for higher education established in 1872, at Fayetteville, Arkansas. There were in attendance in all departments in the autumn of 1915, 783 students. The faculty numbered 75. There were no notable changes in the faculty, and no noteworthy benefactions were received. The library contains about 25,000 volumes. The president is J. C. Futrall, M.A.

ARMENIAN CASE. See UNITED STATES AND THE WAR.

ARMIES. See MILITARY PROGRESS, and section Army, under the various countries.

ARMSTRONG, PAUL. American dramatist, died Aug. 30, 1915. He was born in Kidder, Mo., in 1869, and began life as a sailor on the Great Lakes, eventually becoming master of a steamer. Later he went to New York, and engaged in journalism. During this period he wrote his first play, A Night in the Police Station. His first success was The Heir to the Hoorah, produced in 1904. This was followed by Salomy Jane (1905) and by his greatest

success, Alias Jimmy Valentine (1909). He collaborated in Via Wireless (with Winchell Smith, 1909), Going Some (with Rex Beach, 1909), and Deep Purple (with Wilson Mizner, 1911). Nearly all Mr. Armstrong's plays met with unusual success.

ART. See ARCHITECTURE; MUSIC; and PAINTING AND SCULPTURE.

ART EXHIBITIONS. See PAINTING AND SCULPTURE.

ARTILLERY. See MILITARY PROGRESS, and section Army, under UNITED STATES, and under various foreign countries.

ASBESTOS. This has never been produced in large quantities in the United States. The annual production has ranged from 71 short tons in 1890 to 7604 in 1911. In 1914 there was an increase in the output of high grade crude fibre. The total amount of asbestos mined and sold in that year was 1247 short tons, valued at $16,810, compared with 1100 valued at $11,000 in 1913. Asbestos is produced practically in only two States, Georgia and Arizona, though small quantities are mined in California and Virginia. The largest production is from Georgia. Canada is the principal source of the world's supply of asbestos, and large quantities are imported into the United States. These, during the twelve months ending Dec. 31, 1914, amounted to 71,781 short tons, or more than 74 per cent of all the asbestos mined in Canada. The value of the manufactured and unmanufactured asbestos imported for consumption in the United States in 1914 was $1,779,223.

ASIA. See ANTHROPOLOGY; EXPLORATION; and articles on the various Asiatic countries. ASPHALT. Although there was a decrease in the marketed production of asphalt and of manufactured or oil asphalt derived from domestic sources in the United States in 1914, the decrease was more than offset by the greatly increased output of oil asphalt derived from crude petroleum imported from Mexico. The output of natural asphalt amounted to 77,588 short tons, valued at $630,623; the output of oil asphalt from domestic petroleum amounted to 360,683 short tons, valued at $3,016,969; and the output from American refineries of oil asphalt from Mexican petroleum amounted to 313,787 short tons, valued at $4,131,153. In Texas and Utah the output of certain varieties of natural asphalt, required for special purposes, showed an increase. In California there was a notable increase of oil asphalt, derived wholly from domestic petroleum. During the calendar year 1914 asphaltic material and productions to the value of $186,142 were imported. Exports during the same period were valued at $1,247,020.

ASPHYXIATING GASES. See CHEMISTRY, INDUSTRIAL; and MILITARY PROGRESS.

ASQUITH, ᎻᎬᎡᏴᎬᎡᎢ HENRY. See GREAT BRITAIN, History, passim.

ASTRONOMY. During 1915 the American observatories maintained their usual high level of productivity in the field of astronomical research, but, owing to the European war, a marked decrease of activity on the part of the observatories of the Old World was evident. Further details concerning the ninth satellite of Jupiter, discovered by Prof. Seth B. Nicholson in 1914, were published, and this tiny celestial body is now firmly established as a

member of the Jovian family of satellites. The periodic comets discovered by Winnecke and Tempel in 1858 and 1873, respectively, reap peared, and three new comets were found. The death roll of the year included the names of Arthur Auwers, famous for his re-reduction of Bradley's observations and the compilation of star-catalogues; Lady Huggins, the able assistant of her distinguished husband, the late Sir William Huggins, in his epoch-making researches in astrophysics; G. F. Chambers, whose popular works on astronomy have been largely instrumental in spreading a general knowledge of the science; and Theodore Albrecht, chief of the International Bureau for the Investigation of Latitude Variation from its foundation in 1898.

MOUNT WILSON SOLAR OBSERVATORY. In his report of the work accomplished by himself and his assistants at this observatory during 1914, Prof. George E. Hale called attention to the fact that the opening of the second decade of the existence of the observatory was marked by a vigorous revival of solar activity after a prolonged period of calm. The first decade was remarkable for the amount of work accomplished and the new fields of inquiry in solar physics which were opened up. The skill of the director and his co-workers in devising new methods of research was unparalleled in the history of astronomical activity in this field, and it is not too much to say that, in quality, as well as quantity, of output, the observatory stood unrivaled among those devoted to the investigation of the physics of the sun. The methods which were developed and tested during the first decade became firmly established and gave promise of even greater and more important results for the future. The year 1914 was one of the most productive in the history of the observatory. The principal conclusions derived from the work of the year were summarized under 59 heads. Investigations were made of the general magnetic field of the sun, and of the magnetic fields of sun spots. In the case of the former, its existence was shown by 25 lines, representing the elements iron, chromium, vanadium, and nickel (with one unidentified), and all originating at comparatively low levels in the solar atmosphere. Attempts were made to observe the Stark effect due to electric fields in sun spots, but yielded no positive results. On "flash" spectra taken without an eclipse more than 1000 bright lines were measured, surpassing in number those photographed in the same region of the spectrum at eclipses and representing a lower level in the solar atmosphere. A preliminary study of the displacements of solar lines at the sun's centre gave no evidence of the gravitational shift toward the red predicted by Einstein, and the results also failed to support the anomalous dispersion theory advanced by Julius. From an investigation of the levels of the various elements in the sun's atmosphere, the conclusion was reached that the great mass of the vapors present is condensed in a very thin layer close to the photosphere.

The first determinations of stellar parallax with the 80-foot Cassegrain combination of the 60-inch reflector were completed and found very satisfactory. The enormous velocity in space of 577 kilometers per second was found in the

case of the star O.Arg.S.14320. By the measurement of some 600 stars near the North Pole, there was established for stars from the second to the twentieth magnitude a photographic scale, which agrees closely with the Harvard scale for the middle interval but shows divergencies for both bright and faint stars. The disappearance of the chief nebular lines from the spectra of Nova Auriga and Nova Persei was observed; these spectra are now identical with those of certain Wolf-Rayet stars, and it is suggested that the latter may be temporary stars in the later stages of their history. Work on the 100-inch mirror was steadily maintained, an almost perfectly spherical figure being obtained, and preparations for its parabolization were made, including the completion of the 60-inch plane mirror for testing its figure.

POLARITY OF SUN SPOTS. When the magnetic polarity of sun spots was discovered at Mount Wilson in 1907, it was expected that the spot vortices in the northern and southern hemispheres of the sun would have opposite directions of rotation. This expectation was not immediately realized, for spots showing opposite directions of rotation were soon observed in each hemisphere. Professor Hale's discov ery of bipolar spots in 1909, however, afforded a basis for a reconsideration of the whole question, and it was found that, if every spot were classified as the preceding or following member of a bipolar group, as a rule the preceding (or following) spots in opposite hemispheres showed opposite polarities. Later work at Mount Wilson on the polarity of sun spots brought out the interesting fact that, while in the new spot cycle just begun the rule of opposite polarity for the preceding (or following) spots in the two hemispheres still holds, the polarities in a given hemisphere are opposite to those observed in that hemisphere just before the recent spot minimum. Since, in accordance with the well-known law of sun spot distribution, the spots of a cycle appear at first in high solar latitudes and descend as the cycle progresses, it seems likely that the polarity is determined by the solar latitude, and it is suggested that the simplest explanation of the anomaly lies in assuming the existence of high and low latitude zones, distinguished by spots of opposite polarity. Future observations are expected to test this view, and also to reveal what happens in the intermediate

zone.

SOLAR RADIATION CONSTANT. In spite of the extremely accordant values of the solar radiation constant obtained by Messrs. Abbot, Fowle, and Aldrich, of the Smithsonian Institution, from measurements made under diverse conditions of height above sea level, atmospheric transparency, temperature, etc., their results were severely criticized. It was urged by some that their allowance for the heat absorbed by the atmosphere was too low; by others it was claimed that the amount of solar radiation reflected from the outside of the atmosphere was underestimated, and that the true value of the constant should be at least 3, and perhaps as high as 4 calories per square centimeter per minute instead of 1.93 calories, the value deduced by the Smithsonian observers. This value was derived from nearly 1000 measurements made during the period 1903-1914 at

Washington (sea level), Bassour, Algeria (1160 meters), Mount Wilson, California (1730 meters), and Mount Whitney, California (4420 meters). In addition, a series of high-altitude observations, in which sounding balloons were used, was carried out by the Smithsonian Institution in coöperation with the United States Weather Bureau during the summers of 1913 and 1914. On July 14, 1914, a ballon sonde carrying a recording pyrheliometer was released at Omaha, and reached a height of 24,000 meters, or nearly 15 miles. The mean value of the solar radiation constant deduced from the best three records made on this occasion was 1.84 calories, or, when corrected for the radiation scattered and absorbed in the atmosphere above the level attained, 1.88 calories, a value which accords satisfactorily with the value previously obtained.

MARS. Spectograms were obtained at the Lowell Observatory showing strongly intensified oxygen and water vapor bands as compared with similar bands in lunar spectrograms. It was claimed that they prove that the water vapor in the Martian atmosphere is almost entirely confined to the regions over the melting snows at the poles of the planet. The amount of oxygen in the Martian atmosphere was estimated to be about half as great as in

our own.

During the opposition of Mars, Prof. W. H. Pickering issued a series of monthly reports dealing with the planet. The coöperation secured by means of these reports proved so valuable that the formation of a permanent association for the systematic observation of the planet was contemplated.

THE NINTH SATELLITE OF JUPITER. In the YEAR BOOK for 1914, mention was made of the discovery of a new satellite of Jupiter by Prof. Seth B. Nicholson at the Lick observatory on July 21, 1914. The first record of this--the ninth-satellite of Jupiter was obtained on plates which had been exposed for the purpose of securing positions of the fainter satellites of the planet. It is a tiny body of the nineteenth magnitude only, and is therefore even fainter than the eighth satellite near which it was found. Like the latter, it is differentiated from the older satellites discovered by Galileo by its great distance from the primary, its small size, the high inclination of its orbit, and its retrograde motion. The latest determination of its elements gave for its distance from the primary 14,700,000 miles, or about 340 times the radius of Jupiter, and for its period 796 days. The corresponding figures for the eighth satellite are 13,950,000 miles and 739 days, respectively. The close resemblance between the orbits of the two satellites suggests they were added to the Jovian system in the same way, possibly by capture from outside space.

STELLAR PHOTOMETRY. In an important paper read before the National Academy of Sciences, Prof. Joel Stebbins, of the University of Illinois, gave an account of his recent researches on the electrical photometry of stars. In these researches he employed a selenium cell which served as one arm of a Wheatstone bridge, the intensity of the light falling on the cell from any bright source being determined from the diminution of the resist ance of the cell. The difficulty of the problem

becomes apparent when it is realized that the measurement of the light of a star like the Pole Star with a probable error of 1 per cent is equivalent to the detection of a candle at a distance of about a mile. Increased sensitiveness of the apparatus was secured by surrounding the cell with an ice-pack so as to maintain it at a low temperature. Observations were made on eclipsing binaries of three types, namely, Algol, in which a bright star is accompanied by a large faint companion; ß Auriga, a spectroscopic binary with components of practically equal size and brilliancy; and Orionis, in which the components are equally brilliant but unequal in size. The periodicity of Algol, which loses about 5% of its light once in every 69 hours, the temporary eclipse lasting about 12 hours, was discovered in 1783 by Goodricke, who suggested as the cause of the phenomenon the periodical interposition of a large dark satellite. Unless the companion star is entirely dark, there should be another loss of light midway between two successive primary eclipses, but no such loss has ever been observed visually. With the selenium photometer, however, Stebbins was able to detect a diminution of about 6 per cent, proving conclusively that the companion, while dark, is not entirely so. In the case of B Auriga, spectroscopic observation has shown that we have a system of two bodies revolving round each other in a period of about four days. Although it is impossible to separate the two stars in the telescope, still the eclipses of one star by the other can be determined spectroscopically, for, whenever they occur, the spectrum lines are seen single instead of double, as they are when light waves are received from both components simultaneously.

The photometric observations showed that at the precise times when the eclipses take place the light of the system is diminished by 7 per cent, successive diminutions following one another at intervals of half the period. It was estimated that the surface brightness of each body is 12, and possibly 25, times that of the sun, the total light emitted by the system being from 150 to 300 times the solar light. In the case of Orionis, the observations indicated that the two components of the system have almost equal intensities but differ in size, the radius of the smaller being only half that of the larger. Professor Stebbins also succeeded in constructing a photoelectric cell from one of the alkali metals which is twice as sensitive as anything of the kind hitherto available, and far more uniform in its action than the selenium cell. A tenfold improvement over the best obtained with the selenium cell was expected from the later apparatus, and the results of the further prosecution of his researches were awaited with interest.

THE ORION NEBULA. In the YEAR BOOK for 1914, attention was drawn to the spectroscopic evidence of rotation in the Virgo nebula which had been recently obtained by Professor Slipher of the Lowell observatory. Further evidence of nebular rotation was found by Messrs. Buisson, Fabry, and Bourget in their studies of the great nebula in Orion. The interferometer method was used. Interference rings formed with light of known wave-length from the nebula, and the wave-length for this particular ray was then calculated from the size

were

of the rings produced. Any decrease or increase of wave-length is of course due to the Doppler effect, and the radial velocity of the region of the nebula from which the light was derived can be easily determined. It was found that, on the whole, the nebula has a rotary motion about a line running from northwest to southeast, though many irregularities were observed; and that the northeast region is withdrawing at the rate of about 5 kilometers per second relatively to the axis of rotation, while the southwest region is approaching with about the same relative velocity. In the region surrounding the Trapezium a mean radial velocity of 15.8 kilometers per second relative to and directed away from the sun was obtained. The atomic weight of nebulium and the temperature of the nebula were also investigated. It was found that the two distinctive lines in the ultra-violet are emitted by an element of approximate atomic weight three, which agrees with the theoretical atomic weight of nebulium, but the conclusion was reached that the green line usually associated with that element belongs to another element of even lower atomic weight. The temperature of the nebula was estimated to be 15,000°C.

One

MEASURING THE HEAT OF THE STARS. In a recent contribution to the Bulletin of the Bureau of Standards, Prof. W. W. Coblentz described his important work of measuring the amount of heat radiated from the stars. Several previous attempts had been made to determine the amount of stellar radiation. of the earliest was by Sir William Huggins, who employed a thermoelement to measure the minute amounts received from Sirius, Pollux, Regulus, and Arcturus, but his results were qualitative rather than quantitative. Stone, somewhat later, and, quite recently, Pfund, were more successful in their application of the thermoelement to this problem. Stone's observations were confined to Arcturus and Vega, and showed that the former emitted more radiation than the latter in the ratio of 3 to 2. Pfund investigated Jupiter, Vega, and Altair, and concluded that, with one of the largest reflectors and a more sensitive galvanometer, it would be possible to make measurements in the case of stars down to the fourth magnitude. In 1901 Nichols made use of his improved radiometer which was so sensitive that a candle placed at a distance of 5 miles would have given a deflection of 1 mm. on his galvanometer scale. For Arcturus and Vega he found a somewhat higher ratio than that obtained by Stone. The telescope employed by Professor Coblentz was the large Crossley reflector of the Lick observatory. By using for his radiometer a bismuth-platinum thermocouple mounted in vacuo, he succeeded in securing a sensitivity more than 100 times as great as that of the Nichols radiometer, so that a deflection of 1 mm. would be produced by a candle at a distance of 53 miles. Measurements were made on 112 celestial objects, including 105 stars, the bright and dark bands of Jupiter, a couple of Jupiter's satellites, the rings of Saturn, and a planetary nebula. Quantitative measurements of stars down to magnitude 5.3 were obtained, and it was found possible to get qualitative results in the case of stars as faint as magnitude 6.7. Red stars were found to emit from two to three times as much total radiation as

blue stars of the same photometric magnitude. As an indication of the extremely minute amounts of stellar radiation involved, it is stated that, if the radiation from the Pole Star falling on a square centimeter of the earth's surface could be absorbed and conserved, it would take a million years to raise the temperature of one gram of water 1°C, while the total radiation from all the stars similarly absorbed and conserved would require from 100 to 200 years. This is in marked contrast to the solar radiation, which can produce the same effect in about a minute.

MINOR PLANETS. Although the number of minor planets announced as new in 1911, 1912, and 1914 showed some diminution when compared with the numbers discovered annually during the period 1906-1910, there appears to be no indication that the exhaustion of the zone is near. Since the issue of the YEAR Book for 1914, 74 of these small bodies have been reported, and have been assigned provisional designations ranging from 1914 VS to WH, and 1915 WJ to YH, together with 1901a, 1913k to o, and 1914a and b, the single-letter designations being due to belated recognition or reporting. It will be observed that in 1915 we were hearing the end of the second series of double-letter designations. Of the 24 minor planets not properly belonging to 1915, the five designated 1913k to o were discovered by Metcalf at Winchester, Mass.; 1914a and b were found by Beljawsky at Simeis; and 1901a was detected on an old plate exposed by Wolf at Heidelberg as far back as 1901, having been overlooked at the time of its discovery. Of the remaining 16 belonging to 1914, 5 were reported from Heidelberg, 4 falling to the share of Professor Wolf, and 1 to his assistant Reinmuth, while the rest were discovered by Neujmin at Simeis. This year the Heidelberg observatory claimed more than half of the total number of minor planets announced as new, no fewer than 29 having been found by Wolf (27), and Reinmuth (2). Of the remaining 21, 9 were reported from Simeis (7 by Neujmin, and 2 by Beljawsky), 6 by Thiele (Bergedorf), 3 by Tomás Solá (Barcelona), 2 by Palisa (Vienna), and 1 by Demetrescu (Bucharest). One surprising feature of the year's work in this field was the number of long-missing planets which were re-observed. 1915 WJ, discovered by Wolf, proved to be the long-lost 99 Dike, last seen in 1868, the year of its first discovery, and 1915 XU is probably identical with 193 Ambrosia. Other minor planets not observed since their discovery and refound in 1915 were 290 Bruna (1890), 353 RupertaCarola (1893), 392 Wilhelmina (1894), 493 Griseldis (1902), 573 Rebekka (1905), and 594 Mireille (1906); of these, 392 is identical with 1914 WG, 493 with 1915 WK, and 572 with 1915 WU.

Permanent numbers were assigned to the following minor planets: