September 2, 1897J 



NATURE 



423 



Those interested in the properties of kathodic and allied 

 rays, will find quite a series of papers in the last five numbers of 

 the Atti della R. Accadeinia dei Lincei. Among these we would 

 call especial attention to the following : — On the action of 

 electricity on the discharging property induced in air by a-rays, 

 by Prof. E. Villari (vol. vi. part I, p. 343).— On the penetrating 

 power of the same rays, by A. Roiti {ibid. p. 354). — On electric 

 discharge in gases, and on certain phenomena of electrolysis, by 

 Vito Volterra{»'(J/^. p. 389), dealing with phenomena allied to those 

 observed by Sella and Majorana, in connection with the action of 

 Rontgen and ultra-violet rays on the electric spark. — On the 

 electrostatic charges generated by kathodic rays, by Q. Majorana 

 (vol. vi. part 2, p. 16), who finds that the emanation of kathodic 

 rays depends to a certain extent on the position of the anode. — On 

 the discharging action of air after being traversed by .r-rays, by 

 Dr. Adolfo Campetti {ibid. p. 43), who considers that the so- 

 called effects of dispersion by air, modified either by :«:-rays or 

 by combustion, depends on a temporary increase in the con- 

 ductivity of the gas. — On the non-penetration of electric waves 

 into the space enclosed by a metallic shell, by Prof. Augusto Righi 

 {ibid. p. 59). — On the velocity of kathodic rays, by Q. Majorana 

 {ibid. p. 66), who obtains values for the velocity ranging from 

 100 to 600 kilometres per second. — On the double refraction of 

 wood for electro-magnetic waves, by Prof. Domenico Mazzotto 

 {ibid. p. 73), who finds {a) that the index of refraction varies 

 considerably in different woods, and increases with the density ; 

 {h) that in the same wood electric oscillations perpendicular to 

 the fibres are propagated more rapidly than those parallel to the 

 fibres, and, hence, the index of refraction is less for the former ; 

 (< ) that the difference between the two indices is less for dense 

 than for light woods. 



The action of light on various kinds of yeasts has lately 

 been elaborately investigated by W. Lohmann. Kry has 

 shown that the division of the cell in the case of Sacch. 

 •cerevisiiB takes place as vigorously in the presence of moderate 

 light as in the dark, but the action of intense light upon this 

 and other varieties of yeast has been studied by Lohmann. 

 Exposure to the electric light, 11,590 candle-power, was found 

 to exert a distinctly retarding action on the multiplication of 

 these yeast cells. The sun's rays were, however, much more 

 detrimental to their vitality, for after several hours' direct and 

 uninterrupted insolation in the months of May and June, the 

 rise in temperature being prevented by immersion of the agar- 

 dishes containing the yeast cells in water, the latter were 

 entirely destroyed. On the other hand, yeast cells kept in the 

 dark during the same period of time, or only exposed 

 intermittently to feeble sunshine, exhibited distinct multipli- 

 cation. A microscopic examination revealed also a striking 

 morphological difference between the cells kept in the dark and 

 those which had been insolated. Whereas the former pre- 

 sented a perfectly normal appearance, the latter looked 

 shrunken, exhibited irregular contours, and the plasma was 

 drawn together in lumps, chiefly in the direction of the poles of 

 the cells. Similar insolation experiments on other varieties of 

 yeast exhibited the same lethal effect produced on these 

 organisms by prolonged exposure to direct sunshine. 



A NEW edition (the fourth) of Mr. Howard Collins' " Epitome 

 of the Synthetic Philosophy of Herbert Spencer" (Williams and 

 Norgate) has just been published. Mr. Spencer contributes a 

 brief introduction to the volume, which is now a representation 

 in miniature (if the word can be applied to a volume of nearly 

 seven hundred pages) of the whole of his philosophy. — Dr. 

 Max Verworn's "AUgemeine Physiologic" (Jena: Gustav 

 Fischer), the first edition of which appeared early in 1895, 

 has reached a second edition. Shortly after the original work 

 NO. 1453, VOL. 56] 



appeared, its scope and many valuable qualities were described 

 in these columns (vol li. p. 529). The volume has been 

 thoroughly revised, and will doubtless pass through many more 

 editions. English and Italian translations are being prepared. 

 A Russian edition appeared some time ago, but Dr. Verworn 

 states that it was published without his authority. 



The following are among the articles and other publications 

 which have come under our notice within the past few days :— 

 "On the Development and Structure of Dental Enamel," by 

 Dr. J. Leon Williams, in the Journal oi the Royal Microscopical 

 Society (August). The paper is illustrated with several 

 excellent photo-micrographs showing various phases of enamel 

 development.— The Chemical Society has just issued the annual 

 supplementary number of its Journal, containing title-pages, 

 contents, and indexes of volumes Ixix. and Ixx. (1896). To 

 chemists this record of contributions to chemistry must be 

 invaluable. —Following other scientific instrument-makers, 

 Messrs. Howard B. Little and Co. have prepared and issued an 

 illustrated list of apparatus and accessories for work with 

 Rontgen rays. Persons who require an efficient outfit at a 

 reasonable price should see Messrs. Little's list.— A description 

 of the various forms of Australian buUroarers, accompanied by 

 illustrative drawings, is contributed to the Journal of the 

 Anthropological Institute (August), by Mr. R. H. Mathews. 

 The same publication contains papers on the Berbers of 

 Morocco, by Mr. W. B. Harris ; Kafiristan and its people, by 

 Sir George Scott Robertson ; and further discoveries of ancient 

 stone implements in Somaliland, by Mr. H. W. Seton-Karr. — 

 In the Journal of the Royal Horticultural Society (August) are 

 papers on the study of microscopic organisms, and its importance 

 to horticulturists, farmers, and foresters, by Prof. Marshall 

 Ward, F.R.S. ; diseases of plants, by Mr. George Massee ; and 

 the physiology of pitcher-plants, by Prof. Sydney H. Vines, 

 F.R.S. — Dr. C. M. Aikman has sent us a pamphlet on " Sixty 

 Years of Agricultural Science," reprinted from the Agricultural 

 Gazette. — The Quarterly Journal of the Royal Meteorological 

 Society (July), just issued, contains a report of a lecture by Mr. 

 G. J. Symons, F.R.S., on "Meteorological Instruments in 

 1837 and in 1897," with plates illustrating the types of 

 instruments employed sixty years ago and now in meteorological 

 observations. 



The additions to the Zoological Society's Gardens during the 

 past week include a '^loz3imhiKi\xQM.on\f.&y {Cercopitkecus pygery- 

 thrus) from Southeast Africa, presented by Mrs. Charlesworth ; 

 five Australian Bush Rats {Mus arboricola) from New South 

 Wales, presented by Mr. Edgar R. Waite ; two Egyptian 

 Kites {Milvtts agyptius) from South Africa, presented by Mr. G. 

 A. Ogilvie ; a Mountain Ka-Ka {Nestor notabilis) from New 

 Zealand, presented by Mr. Arthur Hope; two Ravens {Corvus 

 corax), British, presented by Mr. W. B. Bingham ; a Turtle 

 Dove {Turtur communis), British, presented by Miss Mallard ; 

 a Purple Sunbird {Cinnyris asiaticits) from India, presented by 

 Mr. Frank Finn ; a Tawny Owl {Syrnium aluco), British, pre- 

 sented by Mr. C. Hastings Bostock ; two Ring-necked Parra- 

 keets {PaLcornis torquatus) from India, presented by Miss M. 

 Parsons ; a European Pond Tortoise {Emys orbicularis), 

 European, presented by Mr. F. E. Bastian ; a Goliath Beetle 

 {Goliathus druryi) from the Gold Coast, presented by Mr. W. 



Durham Hall; a Spider {Mygale, sp. inc.) from South 



Africa, presented by Mr. Rowland Ward ; a Feline Genet 

 {Genettafelina), a Delalande's Lizard {Nucos delalandii), a Puff 

 Adder {Bitis arietans), a Cape Bucephalus {Dispholidus typus), 

 a Rough-keeled Snake {Dasypeltis scabra), two Rhomb-marked 

 Snakes ( Tritnerorhinus rhombeatus), an Infernal Snake {Boodon 

 infer nalis), two Lineated Snakes {Boodon lineatus), a Rufescent 



