136 



NATURE 



[December 7, 1899 



Dr. F. a. Cook, who recently returned with the Belgica 

 expedition, contributes to the December number of Scrihner's 

 Magazine an interesting article, accompanied by a number of 

 illustrations reproduced from photographs, on the possibilities 

 of Antarctic exploration. He shows that important results of 

 immediate practical use to both science and commerce are 

 likely to be obtained by Antarctic exploration. Referring 

 to the need for exploration merely from a geographical point 

 of view, Dr. Cook remarks : — ' ' The actual existence of a 

 land corresponding to what is charted as Graham Land is a 

 matter of considerable doubt. On the map it extends from the 

 sixty-ninth parallel of latitude, northward four hundred miles. 

 But Alexander I. Land, the southern termination, is an island, 

 and we saw no land eastward. The character of the land 

 which may or may not exist between this and the newly-dis- 

 covered Belgica Strait is in doubt. It offers scientific and com- 

 mercial prospects promised by no other new polar region. At 

 the one hundredth degree of east longitude, close to the circle, 

 there is another interruption in the unknown. This is the much 

 disputed Wilkes Land. It is by far the largest land mass in the 

 entire Antarctic area. Including Victoria Land, its better known 

 eastern border, it covers more than one-sixth of the circumference 

 of the globe. In a territory of this extent, even under the most 

 hopeless spread of snow, would it not be strange if something of 

 value and much of interest were not found ? Enderby Land and 

 Kemp Land furnish other problems. They are probably not 

 fixed to the continent, for the American, Morrell, found open 

 sea below them ; but whether they are isolated islands or parts of 

 an archipelago remains to be ascertained. Does Peter Island 

 exist ? The Belgica drifted close to the position assigned to it 

 by Bellingshausen, but saw no land. These are but a few ex- 

 amples of the many geographical problems to be solved in the 

 Far South." 



la \\\& Journal de Physique {oxl^os^vah^x, M. A.-B. Chau- 

 veau discusses the diurnal variations of atmospheric electricity, 

 to explain which no less than about thirty different theories have 

 been proposed, of which four appeared in a single year (1884). 

 M. Chauveau's principal conclusions, based on a comparison of 

 curves from the Bureau central, Batavia, Sodankyla (Finland) 

 Trappes, the College de France, and Greenwich, are as 

 follows: — (i) That the influence of the soil which is greatest 

 in summer (and of which the principal factor probably is the 

 evaporation of negatively electrified water from the surface of 

 the earth) intervenes as a disturbing cause in the diurnal varia- 

 tion. (2) That the general law of variation is represented by a 

 simple oscillation having a maximum in the day, and a minimum 

 (moreover, remarkably constant) between 3.30 and 4.30 a.m. 



From the Bulletin of the French Physical Society we learn 

 that M. Sagnac has given a theory of the propagation of light 

 through matter which supposes that the light waves are trans- 

 mitted by the same ether as in vacuo without the properties of 

 this medium being in any way altered by the presence of material 

 particles ; the only effect of these is to scatter the vibrations in 

 the same manner as small conductors, each of which reflects 

 and diffracts all vibrations of sufficiently great wave-length. 

 The author shows that, without introducing any electromag- 

 netical or dynamical considerations, it is possible to give a 

 purely kinematical explanation of the laws of reflection and re- 

 fraction, the existence of the optic layer, and the existence of 

 refractive indices greater than unity. M. Sagnac shows how 

 the optic phenomena of entrainment of ether by matter can be 

 explained by his hypothesis without the assumption of either 

 an ether denser than the ether of a vacuum or any mechanical 

 reaction between the ether and matter. This kinematical 

 theory of the entrainment of the ether presents no difiiculties or 

 complications in accounting for the existence of dispersion or 

 NO. 1571, VOL, 61] 



double refraction ; and M. Sagnac has extended the theory to 

 the explanation of anomalous dispersion and to the investiga- 

 tion of certain new optic phenomena. 



In the year 1891 the Hydrographic Office of Vienna estab- 

 lished an elaborate service of rainfall and river observations in 

 all the principal river systems. The volumes for the year 1897 

 have just been published and contain results of rainfall observa- 

 tions for no less than 2615 stations, together with tables showing 

 the general distribution of temperature in the Austrian f.mpire. 

 The depth of snow is also regularly gauged at over 40 stations? 

 The work is accompanied by numerous diagrams and by a 

 general discussion of the results for each of the 14 districts into 

 which the service is subdivided. 



We have received the Boletin Mensual of the Manila Ob- 

 servatory for the first quarter of the year 1898. It is satisfactory 

 to note that observations have been regularly recorded at this 

 important observatory, under the direction of the Jesuit Fathers, 

 for the last thirty-three years. The present volume contains 

 hourly and daily means of the principal meteorological and 

 magnetical elements, together with maximum and minimum 

 values for Manila, from self-recording instruments and eye 

 observations made twice daily at a number of secondary stations 

 in the Philippine Islands. It also contains a monthly discussion 

 of the observations and of earthquake phenomena, with curves 

 of the meterological and magnetical elements. 



Messrs. Bailliere, Tindall and Co. have published the 

 fourth edition of " A Synopsis of the British Pharmacopoeia," 

 compiled by Mr. H. Wippell Gadd, with analytical notes and 

 suggested standards by Mr. C. G. Moor. 



Mr. a. C. Seward reprints from the Proceedings of the 

 Cambridge Philosophical Society a paper on the Binney collec- 

 tion of Coal- Measure plants, in which a new genus, Megaloxylon > 

 is described, belonging to the Cyadofilices, and considered by 

 the author as furnishing an additional link between the Palaeozoic 

 representatives of this family and recent ferns. The paper is 

 copiously illustrated. 



The sixth edition of M. Eric Gerard's " Le9ons sur 

 I'Electricite " has been published in two volumes by MM. 

 Gauthier-Villars, Paris. The first volume deals with the 

 general principles of electricity and magnetism, and the theory 

 and construction of dynamo-electric machinery. The second 

 volume is concerned with the most important industrial appli- 

 cations of electricity. The work has increased in size, and 

 many new illustrations have been added. 



The additions to the Zoological Society's Gardens during the 

 past week include a Macaque Monkey {Maca-us cynoinolgus, ? ) 

 from India, presented by Mr. J. A. Ewen, J.P. ; a Brown 

 Capuchin (Cebus fatuellus) from Guiana, presented by Mr. 

 Douglas Mason ; a Badger {Meles taxus), British, presented by 

 Mr. G. A. Bronson ; two Golden Agoutis (Dasyprocta aguti) 

 from Central America, presented by Mr. C. Bevan ; a White- 

 bellied Sea Eagle {Haliaetus leucogaster) from Tasmania, pre. 

 sented by Captain Francis Mayor ; a Common Trout {Salmo 

 fario), British fresh waters, presented by Mr. Arthur Irving ; a 

 Rufous Rat Kangaroo {^-Epyprymntts rufescens, $ ) from New 

 South Wales, two Ornamental Lorikeets ( Trichoglossus ornaius) 

 from Moluccas, a Banded Parrakeet {Palaeornis fascial a), four 

 Starred Tortoises {Testudo elegans) from India, two Undulated 

 Grass Parrakeets {Melopsittacus undulatus) from Australia, a 

 Lapwing {Vanellus vulgaris, var. ), four Bewick's Swans 

 {Cygnus bewicki), European ; two Wrinkled Terrapins {Ckry- 

 semys scripta rugosa) from the West Indies, two Emperor Boas 

 (Boa imperator) from Central America, deposited. 



