April II, 1889] 



NATURE 



5^7 



Mr. T. Workman writes to us from Belfast that, having 

 faUen into a doze on the afternoon of Friday, March 29, he was 

 awakened by the undoubted hum of a mosquito, and thought 

 himself back in Singapore, where he was about fourteen months 

 ago. His first impulse was to drive away the nuisance, but 

 curiosity to know whether it really was what he thought made 

 him forbear, and he was soon rewarded by its settling on his 

 right eyebrow and inserting its stiletto, with the usual sharp 

 result, both to him and to it. Mr. Workman incloses in his 

 letter a sketch of the insect. A mosquito in March in the north- 

 east of Ireland is certainly a rare phenomenon. 



The first part of the Transactions of the meeting held in 

 August 1888, in Paris, for the study of tuberculosis in man 

 and animals, has just been published by M. Masson. It is a 

 volume of 500 pages, and contains much interesting matter. 



Messrs. Macmillan and Co. have issued the second part 

 of vol. ii. of the new and thoroughly revised edition of " A 

 Treatise on Chemistry," by Sir H. E. Roscoe, F.R.S., and C. 

 Schorlemmer, F.R.S. In this volume, the authors treat of 

 metals and their compounds. 



A VALUABLE list of the Coleopterous fauna of the Liverpool 

 district, by Mr. John W. Elli?, has been reprinted from the 

 Proceedings of the Liverpool Biological Society. The list 

 contains nearly 30 per cent, of the British beetles. 



The second part of Prof. E. Strasburger's " Ilistologische 

 Beitriige " (Jena, G. Fischer) has been published. In this part, 

 which is illustrated with four lithographic plates, the author 

 deals with the growth of vegetable cellular membranes. 



Messrs. G. Bell and Sons are about to pablish "Names 

 and Synonyms of British Plants," by the Rev. G. Egerton- 

 Warburton. This is a complete alphabetical list of known 

 British plants, giving, under each, references to its description 

 in Sowerby's "English Botany" (Syme Boswell), "The Lon- 

 don Catalogue of Plants," and the "Floras" of Babington, 

 Bentham, and Hooker. The correct pronunciation of the 

 names is indicated by accents. A list of the most usual i 

 synonyms is appended. j 



We have received vol. ii.. No. 2, of the Proceedings of the ' 

 Tokio Physical Society. It is worthy of note that the report of j 

 the Society is printed in Japanese, in Roman letters, while the I 

 various papers are in English. Amongst the contributions in \ 

 the present number are : effects of stress on magnetization of 

 nickel, by H.Nagaoka ; thermal conductivity of marble, by K. 

 Vamagawa ; an apparatus for purifying mercury, by H. Nagaoka. 



The next Congress and Exhibition of the Sanitary Institute 

 will be held in Worcester at the end of September. Arrange- 

 ments are in progres>-, and will be published shortly. 



At the Central Institution of the City and Guilds of London 

 Institute, Mr. T. Bolas will deliver a course of six lectures on 

 photography, on Wednesday evenings, at 7.30, beginning on 

 May 8. Lectures I. and II. will deal with the use of artificial 

 light in photography ; lectures III. and IV. with photo-mecha- 

 nical printing methods; and lectures V. and VI. with direct 

 contact printing methods. 



The London Geological Field Class under the direction of 

 Prof. H. G. Seeley, F.R.S., will begin the summer excursions 

 this year on May 4, and will continue them on Saturday after- 

 noons thereafter till the end of June. Intending students should 

 apply at once for tickets to the Honorary Secretary, Mr. Walter 

 Lewinton, Lundy House, Willoughby Road, Hampstead, N.W. 



The additions to the Zoological Society's Gardens during the 

 past week include a Macaque Monkey (3/acacus cynomolgris 9 ) 



from India, presented by Mrs. Cox ; a Sinaitic Ibex {Capra 

 sinaitica) from Mount Sinai, presented by Sir James Anderson ; 

 four Black Swans [Cygnus atratus) from Australia, presented 

 by Messrs. James and Alex. Brown ; a Raven (Corvus corax)^ 

 British, presented by Mr. G. F, Hastings ; a Collared Fruit 

 Bat {Cynonycteris coUaris), a Side-striped Jackal {Canis 

 lateralis), born in the Gardens. 



OUR ASTRONOMICAL COLUMN. 



The Luminosity of Venus. — Venus being now favourably 

 situa'.ed, it is a convenient time for making observations with 

 reference to the question of the cause of the recorded so-called 

 phosphorescence. If there be any extensive phosphorescence, 

 as first suggested by Sir William Herschel, or if there be 

 an atmosphere occasionally illuminated by electrical discharges 

 similar to those which produce aurora; in our own atmosphere, 

 or even if there be a meteoritic bombardment, the light observed 

 may possibly give indications of a spectrum of bright lines or 

 bands. 



The Spectra of R Leonis and R Hvdr/E. — A Wolsing- 

 ham Observatory Circular (No. 23, April 2, 1889), by Mr. 

 Espin, states that : "The spectra of R Leonis and R Hydrae 

 I contain bright (hydrogen?) lines, first seen on February 25. 

 Observations confirmed, through the kindness of Mr. Common, 

 j by Mr, Taylor, at Ealing, who sees two in R Leonis and one 

 in R Hydrte." The spectra of these two important variables 

 j have hitherto been simply described as being of Group II 

 (Lockyer), indicating, according to Mr. Lockyer, carbon-fluting 

 radiation and metallic- fluting absorption. Mr. Espin's observa- 

 tions are of very great interest in connection with the meteoric 

 theory as to the cause of variability in this class of stars. It 

 will be remembered that the variability is ascribed to the effects 

 of a cometic swarm revolving round a central one, the maximum 

 occurring at periastron passage, when the revolving swarm 

 passes through the outliers of the central one. It was predicted 

 that, under these conditions, bright lines would make their ap- 

 pearance, and the jrediction has now been verified in the most 

 complete manner. Both the stars observed by Mr. Espin were 

 near their maxima, that of R Leonis occurring on March 23, 

 and that of R Hydra; on February 17 {Ann. du Bur. ties Long., 

 1889). It may also be remembered that bright lines have been 

 seen in R Cygni and o Ceti when near their maxima. The 

 meteoric theory is therefore greatly strengthened by these obser- 

 vations. The importance of making further observations of 

 these stars, with special reference to the disappearance of the 

 bright lines, is obvious. 



The Sun-spot Minimum. — Prof. Tacchini has recently 

 communicated to the Lyncei of Rome (vol. v. series 4a, March 

 3, 1889), a note by Prof. Ricco on the days on which the solar 

 surface was entirely free from spots, during the years 1885-6-7-8. 

 It appears from the tables given that in 1885 there were only 

 six days on which no spots were visible, whilst there were fifty- 

 one in 1886, ninety-eight in 1887, and 140 in 1888. The 

 maximum number of blank days occurring in one month was in 

 November 1886, there being no spots on twenty-six days of that 

 month. There were twenty blank days in October 1886, eighteen 

 in July, and sixteen in May of the same year. A second ta le 

 is given, showing the total numbers of days on which no sp s 

 were visible during the years 1872-88 inclusive, and also the 

 greatest number of consecutive days on which there were no 

 spots durmg the same years. From this it appears that the 

 greatest number of blank days was 248 in 1878, the last minimum 

 period, whilst in 1872, 1882, and 1884, spots were visible every 

 day. It is suggested that the approaching minimum will occur 

 in 1889-90. In 1879 there were thirty-nine consecutive days oq 

 which no spots were recorded, this being the maximum number 

 in any one year ; the greatest number since then was seventeen 

 in 1888. 



Discovery of a New Comet. — A faint comet was dis- 

 covered by Mr. E. E. Barnard, Lick Observatory, on March 31. 

 The position of the object was as follows : — 

 March 31, I7h. 19m. G.M.T., R.A.sh. 20m. 50s. ; N.P.D. 

 73° 53' o". 

 It has since been observed at Copenhagen : — 

 April 4, 8h. 51m. G.M.T. ; R.A = 5h. 17m. 56s. ; N.P.D. 

 = 74" o' 55". 



