October 27, 1904] 



NATURE 



innrie-i at a large number of stations in neighbouring 

 colonies and in German South-West Africa. At the request 

 of the Admiralty circulars were issued to all observers at 

 ■second order stations south of 30° south latitude asking 

 them to take observations at Greenwich noon, in connection 

 with the National Antarctic Expedition. 



The L.S. Hydrographic Office fias issued a handy 

 pamphlet of instructions, prepared by Mr. J. Page, for the 

 use of the voluntary meteorological observers who contribute 

 Information for the U.S. Monthly Pilot Chart; it will also 

 be found very useful for all observers at sea. The number 

 of vessels regularly engaged in its service exceeds 1800, 

 .;ind the list embraces the merchant marine of all nations, 

 all the vessels of the U.S. Navy, and many foreign cruisers. 

 The form of weather-register now in use was adopted in 

 1SS8; it provides only for a single daily observation, to be 

 made at Greenwich noon, instead of the old form recom- 

 jiiended by the International Maritime Congress held at 

 Brussels in 1853, which provided for observations at several 

 Jiours. The registers are generally returned by post in a 

 foolscap envelope at the end of each month, and supply the 

 information required for laying down tracks of storms, and 

 for the preparation of mean values for each month, 

 3)ublishp(l in the valuable monthly pilot charts, to which 

 notice has frequently been directed in our columns. 



.•\n interesting article on the development of the theory 

 of electrolytic dissociation is contributed to the Popular 

 Scifiicc Monthly (September) by Prof. Svante Arrhenius. 



Is the Transactions of the Academy of Science of St. 

 Louis, Prof. Francis E. Nipher discusses the speed of the 

 trotting horse as a function of the time, and applies the 

 <>mpirical equation s = a+be-'-^ to connect the speed s with 

 the time ( in the problem or problems, of which he gives 

 nuniiTiial illustrations. 



Ix a short but suggestive paper contributed to the Popular 

 Science Monthly (September), Dr. Allan McLaughlin dis- 

 cusses the problem of Hebrew, Magyar, and Levantine 

 immigration. The first part deals with the persecution of 

 the Jewish race in Europe, and the serious problem which 

 America has to face in the building up of large ghettos in 

 towns like New York by the overflowing stream of 

 immigrants. Of the Magyar race only 27,124 subjects were 

 landed in -America in 1903, and these appear to be ideal 

 immigrants but for their tendency to return to Europe. In 

 regard to Levantine races, we are told that " the Greeks 

 are the best of this rather bad lot." 



Sever.al interesting papers on radio-activity are contained 

 in recent numbers of the Atti dei Lincei (xiii., 3, 4, 5). In 

 the first of these numbers Drs. G. Martinelli and A. Sella 

 give measurements of the radio-activity of the pozzolana 

 from the neighbourhood of Rome. In the next Dr. G. 

 Martinelli describes experiments to ascertain whether the 

 reactions involving loss of weight (according to the theories 

 of Landolt, Sanford, Ray, Heydweiller and others) are 

 accompanied by radio-active phenomena. A figure is given 

 of the apparatus, in which the reactions were produced 

 inside a closed vessel in a dish placed under the electro- 

 scope : but though each experiment was continued for two 

 hours no positive results were obtained. Lastly, Messrs. 

 G. Pellini and M. Vaccari discuss the chemical actions pro- 

 duced by radium. They find that there are many chemical 

 reactions produced by light on which radium has no effect, 

 and that, as a general rule, the actions most affected are 

 those provocated by ultra-violet light or Rontgen rays. 

 NO. 1826. VOL. 70] 



We have received a reprint of ;• paper by Prof. H. Geitel 

 which is published in the Jahrbuch der Radioaktivitixt und 

 Elektronik under the title " Elektrizitatszerstreuung und 

 Radioaktivitiit." It forms a valuable summary of the de- 

 velopment of the study of terrestrial electricity from the 

 time of Coulomb to the present. 



In No. 7 of the Bulletin of the Royal Academy of Belgium 

 M. H. Gillot publishes an experimental investigation of the 

 properties of mixtures of the sugars and of the polyhydric 

 alcohols. Melting-point curves are given for binary 

 mixtures of saccharose, lactose, glucose, mannitol, and 

 dukitcl, which are of importance because they indicate the 

 non-existence of isomorphism between these substances. 

 On the other hand, the presence of more than one eutectic 

 point in many of the curves probably means that in these 

 cases definite compounds are produced. 



.■\ PROSPECTUS has been issued by the Berlin Wireless 

 Telegraphy Company, " System Telefunken," which de- 

 scribes the organisation and scope of the company and the 

 character of the apparatus covered by its patents. The 

 company is an amalgamation of Messrs. Siemens and 

 Halske and the Allgemeine ElektricitSts-gesellschaft of 

 Berlin, and its system a combination of the Braun-Siemens 

 and the Slaby-Arco systems. The company has already 

 equipped more than fifty German warships with its appli- 

 ances, and its system has been adopted by the United States 

 Navy. An especial feature of the prospectus, which is 

 e-xcellently illustrated, is the description of a portable 

 apparatus designed for military field service. The trans- 

 mitter and receiver are arranged so that a variation of 

 several hundred per cent, in the wave-length of the electric 

 waves can be rapidly made ; in this manner disturbances 

 caused by the enemy may be eliminated. 



Mr. H. J. Glaisiier, of Wigmore Street, will shortly 

 publish " X-Rays ; their Treatment in Cancer and other 

 Diseases," by Mr. R. J. Cowen. 



Prof. Meldol.a has completed vol. i. of " The Chemical 

 Synthesis of Vital Products and the Inter-relations between 

 Organic Compounds," -which is to be published by Mr. 

 Edward Arnold on November i. 



The svllabus of meetings for the session 1904-5 of the 

 Hampstead Scientific Society gives full particulars of the 

 subjects for the general meetings and for the separate 

 meetings of the natural history, photographic, and astro- 

 nomical sections. 



A NEW edition of Mr. Joseph Y. Bergen's " Elements of 

 Botany " has been published by Messrs. Ginn and Company. 

 A more careful study has been made in this edition of 

 typical cryptogamic forms, and an outline of the ecological 

 classification of plants has been added, as well as chapters 

 on the ecology of leaves and the evolutionary history of 

 plants. 



■ Messrs. Heffer asd Sons, Cambridge, have in the press 

 a book by Mr. S. W. Cole entitled " Exercises in Practical 

 Physiological Chemistry." The book, which is written for 

 the use of medical students, is essentially a laboratory book, 

 only those exercises being included which the author has 

 found can be carried through in ordinary class work. 



Mr. W. B. Clive has published a revised and rewritten 

 edition of " First Stage Magnetism and Electricity," by 

 Dr. R. H. Jude. The section dealing with electrostatics 

 has been curtailed and simplified, and a more practical 



