58o 



NATURE 



[October 15, 1903 



its scientific side by chemists and others, but the artistic 

 aspects of the photographer's work are dealt with in a 

 helpful manner by experienced writers. The magazine is 

 admirably illustrated by a profusion of well executed plates, 

 and is published by Messrs. Hodder and Stoughton. 



Messrs. F. E. Becker and Co., of Hatton Wall, London, 

 are manufacturing cheap electric switchboards for use in 

 physical laboratories supplied with continuous current, de- 

 signed by Mr. William Bennett, of the Gravesend Technical 

 School. It is claimed that by this method it is impossible 

 fo"- students to short circuit the mains, as only one wire is 

 carried round the room. A switch block is provided in each 

 working place, and all students have the same current, but 

 any student can switch the current on or off without in- 

 terrupting others. The boards are supplied with resist- 

 ances, instruments for measuring current, and other neces- 

 sary adjuncts. 



We have received the thirty-sixth volume, that for 1902, 

 of the Journal and Proceedings of the Royal Society of New 

 South Wales. The original papers contained in the first 

 part of the volume are seventeen in number, and many of 

 them are illustrated by plates, of which there are no less 

 than twenty-one. The volume concludes with the annual 

 address delivered to the engineering section of the Society, 

 and two papers also read to the same section. As abstracts 

 of the papers read before the Society are periodically pub- 

 lished in Nature, it only remains to be said that the scien- 

 tific work of the Society, as represented by the contents 

 of the volume before us, does honour to the colony of New 

 South Wales. 



The additions to the Zoological Society's Gardens during 

 the past week include two Black Lemurs (Lemur macaco) 

 from Madagascar, presented by Mr. Walter Barnes; a 

 South African Hornbill (Bucorvus cafer) from South Africa, 

 presented by Mr. W. Champion ; two Larger Patagonian 

 Conures (Cyanolyseus hyroni) from Chili, presented by Mr. 

 E. C. Davids ; two Grey-winged Ouzels (Merula boulboul) 

 from India, an Adelaide Parrakeet (Platycercus adelaidae) 

 from Australia, three Derbian Sternotheres (Sternothaerus 

 derbianus) from West Africa, two Adorned Terrapins 

 (Chrysemys ornata) from Central America, four Brazilian 

 Tortoises (Testudo tabulata), four Orbicular Horned Lizards 

 (Phrynosoma orbiculare) from Brazil, deposited. 



OUR ASTRONOMICAL COLUMN. 



Reported Discovery of a Nova. — A telegram received 

 from the Kiel Centralstelle on October 5 announced that 

 Prof. Wolf had discovered what was probably a new star 

 on the evening of September 21. He found the position of 

 the object, reduced to the equinox of 1903, to be R.A. = 

 2oh. 14m. 6-8s., Dec. = -1-37° 9' 49", and reported that its 

 spectrum was of the nebular type. 



A further communication received from Kiel announces, 

 however, that a telegram received from Prof. Pickering 

 states that the object is not a Nova, but a variable having 

 a spectrum of the fourth type, whilst another telegram from 

 Prof. Hale announces that Barnard has identified the sup- 

 posed Nova with the star B.D. -h 37°.3876 (R.A. = 

 2oh. 14m. 6.8s., Dec. = -f-37° 9' 47"). and found the colour 

 to be "very red." Dr. Parkhurst determined the magni- 

 tude of the variable on October 5, and found it to be io-6. 



1903-4 Ephemeris for Winnecke's Periodical Comet. — 

 The elements and ephemeris of Winnecke's comet for its 

 appearance during 1903-4 have been calculated by Herr C. 

 Killebrand, of Graz, and are published in No. 3907 of the 

 Astronomische Nachrichten. The elements and part of tht 

 ephemeris are given below : — . - 



NO. 1772, VOL. 68] 



M = 



Epoch = igo4 /an. 24-0 (M.T. Berlin). 

 o 28 I "61 



Diameter of Neptune. — Herr C. W. Wirtz, Strassburg, 

 publishes the results of a series of measurements of the 

 diameter of Neptune, made by him during the period 

 December, 1902-March, 1903, in No. 3907 of the Astrono- 

 mische Nachrichten. As the mean result of forty-nine 

 measurements, made on twenty-six evenings, he obtained 

 2". 303 with a possible error of ±o".044 for the value of the 

 diameter. 



Taking the value of the solar parallax as 8''.8o, and 

 Bessell's dimensions for the earth, this gives the actual 

 diameter of Neptune as 50,251 km. and the mean density 

 of the planet as 154, the density of the earth being taken 

 as 5-53- . 



The Opposition of Eros in 1905. — In No. 73 of the 

 Harvard College Observatory Circulars Prof. Pickering 

 publishes an ephemeris for Eros during the opposition of 

 1905. 



This ephemeris gives the Julian Day, the date, the R.A. 

 (1900) and Dec. (1900), the logarithms of the distances from 

 the sun and earth respectively, and the computed magnitude 

 for every tenth day from November 21, 1903, to December 

 20, 1905 ; it has been obtained by interpolation from an 

 ephemeris, for intervals of forty days, computed by Mr. 

 F. E. Seagrave from the elements published in the Berliner 

 Jahrbuch for 1905. 



As seen from' the ephemeris, the opposition of Eros during 

 1905 will be one of the most unfavourable oppositions that 

 can possibly occur, for the computed magnitudes never 

 e.xceed the twelfth. Prof. Pickering recommends that 

 observations of the light variations, both photographic and 

 visual, should be made during the opposition, although Prof. 

 Bailey, working with the 13-inc'h Boyden telescope at 

 Arequipa during the present year, has obtained an excellent 

 set of light-turves of this planet. In general the position 

 of the planet in the sky, during the 1905 opposition, will 

 be nearly opposite to that which it occupied during the 

 spring of 190 1, when its variability was discovered. 



The Royal University Observatory, Vienna. — The 



sixteenth annual volume of the Vienna Observatory Publi- 

 cations contains the details of the " zone observations " for 

 the zone —6° to —10°, made in accordance with the pro- 

 gramme of the Astronomische Gesellschaft for its star 

 catalogue, and collected by Dr. Johann Palisa. The observ- 

 ations were made with the iif-inch Clark refractor, and 

 the tables give the position for 18750, together with the 

 usual reductions. 



The same instrument was also used by Herr J. Rheden 

 for observing the opposition of Mars during the period 

 December 21, 1898-March 16, 1899, and the results of these 

 observations, including eight excellent coloured reproduc- 

 tions of Herr Rheden 's drawings, forni the second part of 

 the publication. 



The third and last section is devoted to the meteorological 

 observations made during the years 1897, 1898, i8q9 and 

 1900. 



