Nov. 30, 1876] 



NATURE 



107 



OUR ASTRONOMICAL COLUMN 



Change or Colour in a Star. — Dr. Klein of Cologne first 

 directed attention to a periodical change of colour in the star a 

 Ursae Majoris, from yellow to an intense fiery red, and estimated 

 the duration of the period to be about five weeks. In a com- 

 munication to the Astronomische Nachrichten, he gives observa- 

 tions by Herr Weber from August 22, 1876, to October 24, 

 which support his inference. Thus on September 5 and October 

 10 the star was considered " stark feuerroth " and "feuerroth, 

 tie*," while on August 22 and October 24, it was noted 

 "weissgelb" and " gelb, schwach blaulich " respectively : from 

 September 5 to October 10 is a period of thirty-five days, con- 

 firming the earlier estimation by Dr. Klein. Herr Weber ob- 

 served with a Steinheil achromatic of 2j inches aperture, and 

 3^ feet focal length with a power of 90. Probably since the suspi- 

 cion of a regular change of colour was made known, the star has 

 engaged the attention of other amateurs, who may be able to add 

 something to the evidence pro or con. 



New Doublk Stars. — Mr. Ormond Stone, Director of the 

 Observatory, Cincinnati, has circulated a list of fifty double stars, 

 varying in distance from o"'8 to 8"*o, which are assumed to be 

 new, and which have been recently found by Mr, Howe with 

 the eleven-inch refractor ; the whole are included between 8° and 

 40° south declination. Positions are given for 1880, with esti- 

 mated angles and distances, and the magnitudes of the com- 

 ponents. Since the number of rapidly-revolving double-stars is 

 probably much greater than at present known, it appears very 

 desirable that micrometrical measures of objects newly discovered 

 should be at once placed upon record, in place of merely esti. 

 mated angles, which form no satisfactory starting-points for the 

 calculation of orbits. 



The JBinary Star ?j Cassiope^. — Dr, Gruber, of Buda- 

 Pesth, has investigated elements of this binary, from normal 

 position-angles formed with the aid of Duner's orbit. His 

 figures agree as nearly as can be expected in such a case with 

 those obtained by the careful calculation of Doberck. With the 

 value of annual parallax obtained by O. Stnive, viz., o""i54, we 

 find— 



Gruber. Doberck. 



Mass of the system 4*632 ... 5256 



Semi-axis major 56*097 ■•• 63'83l 



The sun's mass is taken for unity, and the semi-axis major is 

 expressed in mean distances of the earth from the sun. Dr. 

 Graber's period is 195!^ years. 



In the only two cases which we are at present able to com- 

 pare with that of rj Cassiopese we have for a Centauri, mass of 

 system = 2'2 sun-masses, while for 70 Ophiuchi the similar 

 value is 3*1 . 



The Mass of Neptune. — It is understood that M, Leverrier, 



from his final researches on the motion of Uranus, obtains a 



sensibly larger value for the mass of Neptune than has been 



-igned by Prof. Newcomb, and one approximating to that 



;:ich was inferred many years since from Mr. Lassell's direct 



measures of the distances of the satellite. 



The Nautical Almanac for 1880 has been published 

 ring the last week. The ephemeris of the planet Saturn, 

 ., iiich since the appearance of the almanac in its improved form 

 has hitherto been founded upon Bouvard's Tables, is computed 

 from heliocentric plans communicated by M. Leverrier in advance 

 of the publication of his new tables in vol. xii. of the Annalcs of 

 the Observatory of Paris ; the number of standard stars has been 

 iacreased from 149 to 197, and in extending Damoiseau's Tables 

 of Jupiter's satellites, certain corrections supplied by Prof. 

 Adams have been introduced. 



The impression of the Nautical Almattai now considerably 

 exceeds 20,000 copies. 



METEOROLOGICAL NOTES 



Accelerated Transmission of Weather Maps.— The 

 N'ew York Herald oi November 7 publishes a map of the weather 

 of that morning, exhibiting the lines of atmospheric pressures 

 and of the temperatures over the United States. The meteoro- 

 logical charting which was finished at the Central Oflice in 

 Washington at 10 a.m. was immediately transmitted from Wash- 

 ington in facsimile by telegraph to Philadelphia, where it was 

 received at 10.30 A.M. It was shortly thereafter published in the 

 supplement of the New York Herald of the same day, being the 

 first occasion on which such telegraphic charting had appeared 

 in any newspaper. The fact of telegraphing and printing such 

 charts solves one of the greatest difficulties of exchanges of 

 Weather Reports. It may now be regarded as only a question 

 of time when the more important newspapers of our .British 

 large towns will be in a position to present their readers every 

 morning with a chart of the weather as existing only two or three 

 hours before going to press ; and indeed it, will not be till this 

 result be effected that the practical utility of weather warnings 

 will be properly developed, owing to our close proximity to the 

 Atlantic and the rate at which our weather-changes pass. to the 

 eastward. 



Great Storm of Wind at Sydney. — Mr. Russell, the 

 Government astronomer at Sydney, reports that during a heavy 

 storm of wind which occurred in that part of Australia on Sunday, 

 September 10, the wind, in a gust lasting one or two minutes, 

 attained the extraordinary rate of velocity of 153 miles per hour, 

 as ascertained by Robinson's cup anemometer ; and that during the 

 twelve minutes, from 12, 18 to 12.30 a.m. 22^ miles of wind passed 

 the Observatory, being at the rate of 112 miles per hour. This 

 extraordinary recorded velocity may be regarded as a new con- 

 tribution to meteorological observation, and we look with much 

 interest to the description which will doubtless be given of the 

 method by which it was determined. It scarcely admits of a 

 doubt that the maximum velocity or force of the wind that occurs 

 in great storms is frequently much understated. 



The Temperature of the Northern part of the At- 

 lantic, — An important contribution to the physics of the North 

 Atlantic appears in the November number of /".f/^/waww'j Geogr. 

 Mittheilungen, in a paper by Prof. Mohn on the temperature of 

 the sea beween Norway, Scotland, Iceland, and Spitzbergen 

 The material employed in the discussion consists of the obser- 

 vations collected by the Norwegian Meteorological Institute from 

 the lighthouses on the coast of Norway and from Norwegian 

 ships, and the observations published by the Scottish Meteo- 

 rological Society from their stations in- Scotland, Faro, and 

 Iceland — the observing stations, exclusive of the ships, num' ering 

 twenty-two. At places where observations only for two or three 

 years are available, they are reduced to the longer period of the 

 nearest station by the process of differentiation, with the result 

 that virtually the averages are all good and fairly comparable with 

 each other. The results are represented on seven charts, well 

 executed in colours, showing by six distinct shades, as well as by 

 isothermal lines, the distribution of temperature over this portion 

 of the Atlantic for each set of two months and for the year, and 

 the changes in the positions of the same temperatures from sea- 

 son to season. The outstanding feature of the charts is a strong- 

 marked warm thermal axis, taking a north-easterly direction 

 about 150 miles to westward of Scotland and Norway, extending 

 even beyond the North Cape. Along this line of warm water 

 temperatures are considerably higher than elsewhere in the same 

 latitude. On the July-August chart, however, the warm axis 

 approaches much nearer to the coast of Norway, and extends 

 only from off the Naze to about lat. 66'', From June to Septem- 

 ber the North Sea is coldest on the_ Scottish coast and warmest 

 in the Skagerak, but during the rest of the year this is reversed. 



