June 30, 1904] 



NATURE 



205 



OVR ASTRONOMICAL COLUMN. 

 Astronomical Occurrences in July : — 

 luly 2. Ilh. 7m. Minimum of Algol (;3 Persei). 



6. I3h. Conjunction of Jupiter and Moon. Jupiter 



1° 49' N. 

 9, ijh. 24m. to ijh. 44m. Moon occults 71 Tauri 



(mag. 4-6). 

 ,, I4h. 5m. to I4h. 58m. Moon occults 9' Tauri (mag. 3 '9). 

 ,, I4h. 12m. to I5h. om. Moon occults 6- Tauri 



(mag. 3-6) 

 „ I7h. 31m. to i8h. 24ni. Moon occults o Tauri (mag. i"i). 

 II. lih. 34m. to 13)1. 28m. Transit of Jupiter's Sat. III. 



(Ganymede). 

 15. Venus. Illuminated portion of disc = 0'999, of Mars 



= 0-995. 

 18. I5h. 41m. Transit (ingress) of Jupiter's Sat. III. 



(Ganymede). 

 25. 9h. 38m. Minimum of Algol O Persei). 



27. Ceres stationary 3^° S. of a Scorpii (Antares). 



28. Saturn. Major axis outer ring = 43"'33. Minor axis 



= io"-87. 

 28-30. Epoch of Aquarid meteoric shower (Radiant 

 339°- 11°)- 



Smithsoni.an Institution igoo Eclipse Results. — No. 

 1439 of the Publications of the Smithsonian Institution is 

 devoted to a splendidly illustrated account of the equip- 

 ment and work of the expedition sent out by the Astro- 

 physical Observatory, under the superintendence of Prof. 

 I.angley, to observe the total solar eclipse of May, 1900. 



In chapter i. the director, who was aided throughout by 

 Mr. C. G. Abbot, gives a concise account of the objects of, 

 and the preparations for, the expedition. Chapter ii. de- 

 scribes the establishment of the eclipse camp at Wadesboro, 

 North Carolina, on the same field as the Yerkes expedition 

 under Prof. Hale. 



The loan of a 12-inch lens of 135 feet focal length by 

 Prof. Pickering made the photography of the inner corona 

 one of the most important objects. In summarising the 

 results in chapter iii., Prof. Langley notes, among other 

 things, that large prominences were observed, and appeared 

 10 be associated with regions of coronal disturbance. Bolo- 

 metric observations of the inner corona showed that the 

 heating power of its radiations was unexpectedly small. 

 The search for an intramercurial planet was made with a 

 camera of 3 inches aperture and 11 feet focus, and several 

 suspicious images appeared on the plate, but as there was no 

 confirmatory second photograph the results were incon- 

 clusive. Prof. Langley recommends a similar instrument 

 for future observers. 



The twenty-two beautiful plates which accompany the 

 report display photographs of the observers and their instru- 

 ments as erected, the corona, and parts of the inner corona. 



The Orbit of the Comp.inion to Sirius. — From a dis- 

 cussion of numerous observations of its position angle and 

 distance, Herr O. Lohse, of Potsdam, has determined the 

 following elements (for 19000) for the orbit of the small 

 coinpanion to Sirius : — 



T= 1894-337 (1844-956) 

 U = 5o-38i 

 " = -7°'i4559 

 < =0-598 



Si =44 -12 



t =39° '9 1 



CO =2I2°-20 

 a = 7'-427 



.\ comparison of the observed places with those calculated 

 from the elements, for various dates since 1862, shows that 

 the elements are fairly correct, the mean error in position 

 angle being generally less than 1°, and in distance less 

 than o"'2. 



.\n ephemeris, for the years 1900-1912 inclusive, calcu- 

 lated from these elements, gives the position angle at the 

 commencement of the present year as ii6°-2, and the 

 distance as 6"-6. Observations made at Yerkes on October 

 19 and 26, 1903, gave ii5°-97, 6"-3i. and ii5°o6. 6"-33, as 

 the respective position angles and distances for those dates 

 (Astronomischc Xachrichten, No. 3955). 



Observations of Jupiter during 1903. — The results of 

 numerous observations of Jupiter which were made at 

 Juvisy during 1903 are published and discussed by MM. 

 Flammarion and Benoit in the Bulletin de la Sociite 

 astronomique de France for June. From these observations, 

 which agree with those of other observers, it appears that 

 the northern equatorial band progressively diminished 



NO. 1809, VOL. 70] 



during 1C1C.3, appearing to condense towards the southern 

 edge. The southern equatorial band appeared to be the 

 centre of great activity, the great red spot forming a marked 

 depression in the band, although not so sharply defined as in 

 past years. 



Several large bright spots appeared in the southern 

 tropical zone, two of which, situated in longitudes 180° and 

 225° respectively, were remarkable. In the southern 

 temperate zone several small white spots were observed 

 which seemed to detach from the southern temperate band 

 a quantity of the material of which the latter is composed. 

 Summarising the observed phenomena, it is obvious that 

 the southern hemisphere of Jupiter is in an active state of 

 disturbance, whilst the northern hemisphere is remarkably 

 c:uiescent. 



Observations of the Satellites of Saturn. — In the 

 Bulletin de la Societc astronomique de France for June, M. 

 Lucien Rudaux publishes the results of a series of observ- 

 ations of five of Saturn's satellites made by him during the 

 years 1892-7 and 1901-3 at his observatory at Donville 

 (.Manche). 



His particular object was to record the changes in the 

 brightness of each satellite, and from his numerous observ- 

 ations he concludes (i) that the satellites have periods of 

 rotation equal to their respective periods of revolution ; 

 (2) that they (especially Japetus) have dark spots, probably 

 permanent configurations, which cause a decrease in the 

 satellite's apparent magnitude when presented to us; (3) 

 consequently the apparent magnitude of each satellite varies 

 periodicallv with the satellite's position in its orbit. These 

 conclusions are certainly justified by the observations of 

 1 itan and Japetus, but in the case of Rhea the result is as 

 yet uncertain. 



The German Royal Naval Observatory.— .\ quarto 

 volume published by the German Naval Observatory under 

 the general title " Aus dem Archiv der deutschen Seewarte " 

 (twenty-sixth annual publication, 1903) contains papers on 

 the following subjects :— (i) On the calculation of lunar 

 distances by'the aid of the Mercator functions; (2) estim- 

 ation of the latitude of Heidelberg Observatory and its 

 variations; (3) the daily variation of the magnetic decim- 

 ation ; (4) the wind variation on the German coast ; (3) on 

 the " going " of the standard clocks of the German Naval 

 Observatory; (6) the definitive elements of comet 1887 II. 

 (Brooks). In the last named paper Prof. Dr. C. Stechert 

 has reduced a large number of observations collected from 

 various observatories, and has therefrom calculated the 

 following definitive elements and the probable errors for the 

 oibit of Brooks's comet (1887 H.) : — 



T = i887 March 17-42759410-0061984 (M.T. Berhn) 

 o) =159° 26' I5"-00±I4"-9I1 

 a =279° 56' i2"-62± 3"-54 -Mean equinox 1887-0 

 / =104° 16' io"-47+ 3"-i8j 

 log •/ =0-2122261 + 0-0000095 

 c =0-9836922 + 00002550. 



Dr. Stechert 's paper is also published in No. 3957 of the 

 Astronomische Nachrichten. 1/ 



An Interesting Meteor Trail. — A peculiar meteoric 

 phenomenon was observed by Senor J. A. Perez at Madrid 

 on October 16, 1903. The meteor first appeared in Perseus 

 at about 10 p.m., and the luminous trail did not entirely 

 fade awav until nearly 12 p.m. In the meantime its shape 

 varied considerably. ' Commencing as an almost closed 

 curve with a loop in it, the loop gradually developed until 

 finally the primary curved trail almost entirely disappeared, 

 leaving only a short faint portion entirely separated from 

 the enlarged loop. Six drawings and a description of the 

 phenomenon are published in No. 16 of Das Weltall. 



THE ROYAL SOCIETY CONVERSAZIONE. 



THE second of the two conversaziones held annually at 

 the Royal Society took place on Wednesday, June 22. 

 Many of the exhibits of recent scientific methods and results 

 on view during the evening were shown at the conversazione 

 held in May, and have already been described (May 19, p. 68), 

 but there were, in addition to these, a number of new objects 

 and experiments, of which a list is here given. 



Spontaneous electrification of radium: Hon. R. J. Strutt. 

 A specimen of radium salt in a glass tube is hung up by an 



