May 30, 1889J 



NA TURE 



109 



thus appears that the figure of about three feet in a century, 

 which was deduced from former observations, cannot be very 

 far from the truth. As to local anomalies, they remain still 

 unexplained. 



The additions to the Zoological Society's Gardens during 

 the past week include two Yellow-fronted Tanagers {Euphonia 

 flavifrons) from Dominica, presented by Mrs. Herbert; two 

 Manx Shearwaters {Puffimts anglorui7t) from the Scilly Islands, 

 [presented by Mr. F. Hensman ; an Ocelot {Felis pardalis) from 

 South America, deposited ; four Black -tailed God wits {Limosa 

 (tgocephala), European, purchased ; two Indian Muntjacs {Cer- 

 vulus mutitj'ac i 9 ) from India, received in exchange ; a Persian 

 'Gazelle {Gazella suhgutterosa ? ), two Bennett's Wallabys {Hal- 

 maturus bennetti 9 ? ), a Hog Deer {Cervus porcinus S), s. 

 Collared Fruit Bat {Cynonycteris collaris), two Grey Wagtails 

 {Molacilla melanope), bred in the Gardens. 



OUR ASTRONOMICAL COLUMN. 



Comet 1888 e (Barnard, September 2). — The following 

 ephemeris for Berlin midnight for this object is in continuation 

 of that given in Nature, vol. xxxix. p. 616 : — 



June I 



5 



9 



13 



17 



21 



R.A. 

 h. m. s. 

 22 54 27, 

 22 47 38 

 22 40 4 

 22 31 38 

 22 22 16 

 22 II 57 



Decl. 



39 '9 N. 



40-5 



38-1 



32-5 



23-6 



107 N. 



Log r. 



0-3730 

 0-3786 

 0-3842 

 0-3898 



0-3954 

 0-4010 



Log .i. 



0-3441 

 0-3317 

 0-3193 

 0-3070 

 0*2952 

 0-2839 



Bright- 

 ness. 

 . 2-1 

 . 2-1 

 . 2-2 

 . 2-3 

 . 2-4 

 • 2-4 



The brightness at discovery is taken as unity. 



The Motion of Stars in the Line of Sight. — Prof H. 

 C. Vogel, noting the difficulty which has been experienced at 

 the Greenwich and Rugby Observatories in making eye-observa- 

 tions of the displacement of the lines in stellar spectra due to 

 the approach or recession of the stars, has endeavoured to solve 

 the problem by means of photography, and has met with very 

 considerable success. The atmospheric tremors, which are so 

 baffling and often misleading to direct eye-observation, counteract 

 each other and produce little or no effect on the photograph ; 

 and the feebleness of the light of a star when spread out into a 

 long spectrum is overcome by a lengthened exposure. Prof. 

 Vogel gives the following results (in German miles per second) 

 for five stars, of which four have been observed at Greenwich: — 



Star. 

 Capella .. 

 Aldebaran 

 Polaris 

 o Persei .. 

 Procyon . . 



Vogel. 



+ 3-5 



+ 6-5 

 -3"5 

 -1-5 

 -1-5 



Greenwich. 

 + 4'8 

 -f6-8 

 not observed 

 -4-8 

 -08 



The Greenwich observations for 1888, nearly contemporaneous 

 therefore with the Potsdam robservations, give the motion of 

 Procyon as -0-8. The agreement of the individual photographs 

 is very gratifying, and is much closer than that of the eye- 

 measures made on different nights. 



The Latitude of Detroit. — A determination of the 

 latitude of the Detroit Observatory has recently been made by 

 Dr. Ludovic Estes.^ The zenith telescope was employed, and 

 the results were discussed by the method of least squares. The 

 value arrived at after all corrections is 42° 16' 48" -66 ± o"'05i. 

 An interesting point in connection with the observations is that 

 smaller values were obtained from low stars, which seems " to 

 indicate that northern stars are refracted less than southern, for 

 the same zenith distance ; and that, therefore, the layers of the 

 atmosphere, instead of being parallel to the surface of the earth, 

 are depressed more rapidly toward the north " (p. 54). 



The Minor Planet Victoria. — A programme has been 

 prepared by Dr. Gill, of the Royal Observatory, Cape of Good 

 Hope, for observations of the minor planet Victoria at its op- 

 position in 1889 ; the opposition in right ascension occurring on 

 July 16, and the primary object of these observations being to 



' Ann Arbor, Mich. : The Resjister Printing and Publishing Company, 



determine the parallax of the sun from heliometric measures, A 

 list of comparison stars is given, and is so arranged that when the 

 planet is situated at the greatest zenith distance where good ob- 

 servations may be made, one comparison star may be below and 

 another above it, the measurement by the heliometer of the 

 difference of two nearly equal and opposite distances giving the 

 most accurate result obtainable. 



Victoria has a zenith distance of 62° at an hour-angle of 

 4h. for the Cape, 2h. for European Observatories, and 3h. for 

 Newhaven. A list is given of the limits of hour-angle during 

 which observations of the planet may be made from June 10 to 

 August 29. 



The corrected ephemeris of the planet has been computed, and 

 it is hoped that co-operating meridian Observatories will deter- 

 mine the places of the thirty-seven comparison stars with the 

 meridian circle, and at the same time procure as mmy meridian 

 observations of the planet as possible. Provided that means 

 exist for determining the distortion of the photographic film, and 

 the optical distortion of the field, photographs taken in both 

 hemispheres showing the planet lengthened out so as to form a 

 straight line, whilst neighbouring stars are well defined, are 

 available for the determination of parallax. Dates are also given 

 when photographic observations of Victoria may be advant- 

 ageously combined with heliometer observations. 



Meridian Observations of Iris. — A similar programme to 

 the above was issued by Dr. Gill, in September 1888, for obser- 

 vations of the minor planet Iris ; and Mr. Arthur A. Rambaut, 

 assistant astronomer at Dunsink Observatory, has made 

 observations, with the meridian circle, of the places of the planet 

 and the twenty-eight comparison stars given. The measures 

 vi'\\\\\e.{o\}cciA.m. Monthly Notices R.A. S., March 1889, and ex- 

 tend from September 7, 1888, to January 10, 1889. Between 

 these dates twenty-six observations of Iris were made, and its 

 apparent right ascension and declination found. During the 

 progress of the work two comparison stars were added to Dr. 

 Gill's list. 



ASTRONOMICAL PHENOMENA FOR THE 

 WEEK 1889 JUNE 2-8. 



/'PJ'OR the reckoning of time the civil day, commencing at 

 ^ Greenwich mean midnight, counting the hours on to 24, 



is here employed. ) 



At Greenwich on June 2 



Sunrises, 3h. 50m. ; souths, iih. 57m. 4583.; daily increase 

 of southing, 9-6s. ; sets, 20h. 6m. : right asc. on meridian, 

 4h. 42-3m. ; decl. 22° 15' N. Sidereal Time at Sunset, 

 I2h. 52m. 



Moon (at First Quarter on June 6, 2oh.) rises, 6h. 42m. ; 

 souths, I5h. 2m. ; sets, 23h. 17m. : right asc. on meridian, 

 7h. 46 -Sm. ; decl. 22° 19' N. 



• Indicates that the rising is that of the preceding evening and the setting 

 that of the following morning. 



June. 

 4 • 



8 ... Saturn in conjunction with and l° 47' south 

 of the Moon. 



6 ... — ... Venusat period of greatest morning brilliancy. 

 6 ... 20 ... Mercury stationary. 



Saturn, June 2, — Outer major axis of outer ring = 39 "-i : 

 outer minor axis of outer ring = io"-6 : southern surface visible. 



Meteor-Showeri, 

 R.A. Decl. 



Near /3 Coronse 

 ,, 3 Ophiuchi 

 ,, a Cephei 



228 ... 30 N. ... June 2. 



262 ... 5 N. ... Rather slow. 



317 ... 61 N. ... .Swift; streaks. 



