498 



NATURE 



[March 23, 189; 



off Cape Horn, purchased ; an Upland Goose {Bernicla magel- 

 lanica) from the Falkland Islands, a Mute Swan {Cygnus ohr) 

 European, received in exchange; a Mouflon [Ovis musimon), 

 four Shaw's Gerbilles {Gerbillus shawi), four Barbary Mice 

 {Mus barbarus) born in the Gardens. 



OUR ASTRONOMICAL COLUMN. 



The Melbourne Oi'-servatory. — On September 2 last 

 Mr. Ellery, the Government Astronomer, made his annual 

 report to the Board of Visitors to the Observatory, This 

 report shows that with his staff a great amount of work was got 

 through, the following being a brief summary : — With the 

 meridian circle 3590 observations for Right Ascensions, and 

 2233 for N. P. D. were made, these numbers including the 

 observations for the places of the guide stars used in the 

 astrographic operations. The great telescope, owing to the 

 demands on the staff for the astrographic work, has not been 

 much in use, the routine work having been dropped altogether. 

 It is pleasing to hear that a good start and considerable pro- 

 gress has been made in the part allotted to them in the photo- 

 graphic chart and catalogue of the heavens. Up to June 30, 

 278 plates had been exposed, excluding a great number obtained 

 for purposes of testing adjustments, &c., although Mr. Ellery 

 remarks that the weather since May was anything but inviting 

 for such work. With the photoheliograph 201 sun pictures were 

 obtained. The observations and records relating to terrestrial 

 magnetism, meteorology, and intercolonial weather service, and 

 time distribution have been continued as usual with satisfactory 

 results. In the seventh paragraph of the report Mr. Ellery informs 

 us of the necessity that has arisen for the reduction of expendi- 

 ture. Mr. White, the chief assistant, and Mr. Moerlin, the 

 second assistant, were both called upon to retire on September 30, 

 having attained the age of sixty years, both a considerable loss 

 to the observatory, having served there thirty-one and thirty 

 years respectively, and Mr. Ellery found it necessary to close 

 the observatory workshop, and dispense with the mechanic. In 

 a re-organisation of the duties it will be necessary, he says, to 

 put in abeyance observations with the great reflector, reduce 

 meteorological work, including some photographic registration, 

 stop ordinary extra-meridian observation, except the most im- 

 portant, reduce publications and issue of weather charts, and 

 generally to limit operations to the most important and urgent 

 kind. Such a reduction as this after so many years of smooth 

 working and the loss of two such experienced and efficient 

 officers must fall heavily on Mr. Ellery's shoulders, but we are 

 glad to hear that the new scheme is now in working order. We 

 hope to hear also that Mr. Wallace's services have been retained 

 for the astrographic chart, as Mr. Ellery says in a supplementary 

 report that without him this undertaking will have to be 

 dropped. 



Natal Observatory. — Just as in his former report, Mr. 

 Nevill, the Government Astronomer, is indebted to several 

 ladies for assistance in the observatory, without whose aid he 

 says the numerous astronomical and meteorological computa- 

 tions and reductions could not have been carried out (Report 

 of the Government Astronomer for the year ending June 30, 

 1892). Again, he urges the necessity of removing the transit to 

 another position, this instrument being so close to the equa- 

 torial that only one of them can be used at a time. Besides the 

 usual observations for the comparison of the declinations deduced 

 from observations made at observatories in both hemispheres, 

 by a comparison (Talcott's method) of the zenith distances of 

 northern stars and southern circumpolar stars, the work for 

 determining the latitude of the observatory has been brought to 

 a conclusion and awaits publication. The work, comparing the 

 Greenwich lunar observations from 185 1-1888 with the basis 

 of Hansen's Lunar Tables, comprising a discussion of four thou- 

 sand observations, has been completed, and auxiliary tables, 

 founded on the corrections thus deduced, areno>v being formed. 

 Several observations of Mars were made to determine the dis- 

 tance of the sun, and these are at present being reduced. 



The BiELiDS of 1872, 1885, and 1892.— In " Our Astro- 

 nomical Column" on p. 451 we referred to a note by M. 

 Bredichin on the Bielids, in which he said that from ob- 

 servations made last year it seemed very probable that the 

 densest part of this swarm had undergone perturbations, 



amounting to a recession of the ascending node of nearly 4°, 

 due to the proximity of the planet Jupiter. In the current 

 number of Astronomische Nachrichlen, 3156, he further sug- 

 gests that the swarm has undergone a separation, perhaps into 

 many parts, an analogous case of such a separation having 

 occurred in the comet 1889 I. The force which accomplishes 

 this division he denotes by I. at the commencement of separa- 

 tion and assumes that its direction coincides with the line of the 

 radius vector, being positive and negative when directed towards 

 and f^rom the sun. Denoting by R the radius of the earth at 

 the time of the meeting with the swarm, and the common radius 

 vector, V the true anomaly of this radius in the original orbit, 

 and z\ that in the derived orbit ; representing the angle between 

 this common radius vector and the tangent to the original orbit 

 by ,8, and with any one on the derived orbit by )3i, he educed 

 the following values for the elements of the three orbits, where 

 m is the value of the velocity of commencement for one second 

 of time : — 



Comet Holmes (1892 III.).— M. Schulhof's ephemeris for 

 this comet gives for the ensuing week : — 



I2h. Paris Mean Time. 



Prof. Hale's Solar Photographs.— Among the latest 

 advancements in obtaining photographs of the sun, including 

 simultaneously the chromosphere, faculae, spots, &c.. Prof. Hale 

 has distinguished himself especially in this direction. With 

 regard to the method which he adopts, M. Janssen communicates 

 to the Comptcs Rendus for March 6 (No. 10) a few words. I ask 

 the Academy, he says, "la permission de lui faire remarquer 

 que le principe de cette seconde fente a ete tres neltement 

 indique par nous dans les Communications faites a I'Acadeaiie 

 en 1869, et, avec plus de details, dansune Communication faite 

 au Congres de I'Association britannique tenu a Exeter la meme 

 annee." 



GEOGRAPHICAL NOTES. 



The recognition accorded to geography in the University of 

 Cambridge is not confined to the lectureship. The subject of the 

 English essay proposed for competition this year by members of 

 the University is announced as "The influence exercised upon 

 British literature by the geographical features of the country." 

 Probably "conditions" would convey the meaning better than 

 " features," but apart from such detail, the subject is one likely 

 to turn the attention of competitors to a much neglected matter 

 — the geography of their own country. 



The survey of Greece is being actively carried on by the 

 Austrian Government surveyors, who undertook the work in 

 1889. The primary triangulation is already completed, and 

 while filling in the topographical details of the provinces of 

 Thessaly and Albania the survey officers will be accompanied 



NO. 122 I, VOL. 4.7I 



