24 



SCIENCE. 



[Vol. XIII. No. 310 



SCIENCE 



A WEEKLY NEWSPAPER OF ALL THE ARTS AND SCIENCES. 



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NEW YORK, Jan. ii, 18 



No. 310. 



CONTENTS: 



The Continental Dynamo 



Ball Electbic-Lighting System. 

 The " Ideal " Steam-Engine 



Scientific News in Washington. 

 Does Exposure to the Sun cause 

 the Human Skull to be Harder 



and Thicker? 



Diseases of Menagerie Animals . . . 



The Geological Survey 



The Task of State Weather Ser- 



COMMERCIAL GeoG 



The Development of Commerce on 

 the Kongo 



Health Matters. 

 The Schoolroom as a Factor in Dis- 



Electric Light and Eyes 



Electrical News. 



The Electric Sugar-Refining Pro- 



The Electric Light in Land War- 

 fare 



An Electric Road for Chattanooga 



The Edison Lamp Patents in Eng- 

 land 



The Daft Motor on the Elevated 



Notes and News 23 



Later News from Emin Pacha. — 

 Weather Forecasts. — Interna- 

 tional Languages. 



The American Commonwealth .... 



Aspects of Education 



The Slbjd in the Service of the 



School 



Manual Training in Elementary 



Schools for Boys 



The Roman Catholic Church and 



the School Question 



Vmong the Publishers 



betters to the Editor. 



Two Discoveries in Human Oste- 

 ology by the Hemenway Expe- 

 dition Sylvester Baxter 



The Julien Electric Traction Sys- 

 tem Wm. Bracken 



The Soaring of Birds 



Wm. H. Pickering: 



The Great Lake Basins of the St. 

 Lawrence A . T. Drinnmond 



Color of Katy-did L. N. Johnson 



Various Definitions of Manual 

 Training O. M. Brands 



Color-Blindness Arthur Stevens 



A NUMBER OF REPORTS have been received which dispel the 

 apprehensions in regard to the safety of Emin Pacha. When Os- 

 man Digma's letter arrived, announcing the capture of the Equato- 

 rial Province, this news did not seem unlikely, as it was known that 

 the Mahdi had sent a large expedition up the Nile to attack Emin ; 

 but, as the news came at the moment when Osman expected an 

 attack of the Enghsh, it appeared not improbable that the alleged 

 news might be a trap to prevent the English from taking the of- 

 fensive. A few days ago a Greek trader was reported to have ar- 

 rived from Khartum with the news that the Mahdi's troops had 

 failed to defeat Emin, and additional favorable news is said to have 

 reached Cairo. It seems that ere long the mystery shrouding the 

 events that have taken place in the region of the upper Nile since 

 November, 1887, will be cleared up. 



Those who criticise the weather forecasts of the Signal Ser- 

 vice, and at the same time would like to see discontinued meteoro- 

 logical work which does not directly bear upon practical questions, 

 ought to read carefully the following remarks of Professor Cleve- 

 land Abbe, which are found in the preface to his " Treatise on 

 Meteorological Apparatus and Methods : " " Meteorology can only 

 be worthy of a place among the exact sciences in proportion to the 

 improvements in its methods of observation, and to the extent to 



which they cover the field of the phenomena. Thus the compari- 

 son between theory and observation requires the amount of solar 

 radiation to be known to within i per cent, whereas it is at present 

 uncertain by 1 5 per cent ; it requires the temperature of the air to- 

 be known within 0.5° F., whereas published observations are not 

 always reliable to within one or two degrees ; it requires the gen- 

 eral movement of the air to be known, whereas we have only very 

 uncertain records of the stratum below 100 feet, nothing of the 

 stratum between 100 and 3,000 feet, and scanty record of the cloud- 

 stratum between 3,000 and 30,000 feet. Every effort to explain the 

 ordinary phenomena of storms is embarrassed by the fact that as- 

 sumptions as to the temperature, moisture, and wind have to be 

 made because of the absence of actual observations. Weather-pre- 

 diction will undoubtedly |be more satisfactory when the present 

 round of observations is enlarged so as to include the condition 

 and movement of the great mass of air above us, while at the same 

 time increasing the accuracy of measuring the lowest stratum." 



The committee of the American Philosophical Society ap- 

 pointed to consider an international language continues its work. 

 In a supplementary report made last month, the new attempts at 

 forming an artificial international language are criticised, primarily 

 Professor Melville Bell's " World-English." If the report char- 

 acterizes this attempt as " English written on a new phonetic sys- 

 tem," this view seems to be founded on a misunderstanding of 

 Professor Bell's principle, which advocates a simplification of the 

 English grammar somewhat in the sense of the opinions expressed 

 in the first report of the committee. The greater portion of the 

 supplementary report is taken up by restrictions upon the criticisms 

 of Alexander J. Ellis of the Philological Society of London, who 

 advocates the adoption of Volapiik. It appears that a considerable 

 number of scientists support the scheme of the American Philosophi- 

 cal Society, — to convene a congress for establishing the princi- 

 ples of such a language, — and that most of them concur in the 

 view that it must have those characteristic features toward which 

 Aryan speech is tending. An artificial language of such kind, if 

 generally adopted, would undoubtedly be of great benefit to scien- 

 tists, and make many publications, such as Hungarian, Bohemian, 

 Roumanian, etc., available. But there seems little hope that in this 

 period of nationalism the majority of scientists will forego the claim 

 that their language is the language of the most accomplished and 

 most cultured people of the world, and that it has a right to be- 

 come one of the "world-languages." When this period has passed,. 

 English, French, and German will continue to be better means of 

 international intercourse th^n any artificial language, which is 

 necessarily a dead language, could be. 



BOOK-REVIEWS. 

 The American Commonwealth. By JaMES BryCE, M.P. Lon- 

 don and New York, Macmillan. 2 vols. 12°. $6. 



This is'pre-eminently the book of the season. It has been so 

 long looked for, and so eagerly anticipated, that it will now be even 

 more eagerly read. Dedicated to two such eminent publicists as 

 Albert Venn Dicey and Thomas Erskine Holland, it is, first of all, 

 a publicist's book ; but the style is so clear, and the arrangement 

 so logical, that it can and will be read by thousands of persons in 

 this country whose better instincts stimulate them to improve the 

 quality of their citizenship by studying a careful and impartial ac- 

 count of their national institutions. Professor Bryce's equipment 

 for writing the book is of the highest order, and is not rivalled 

 either in Europe or in this country. As a member of Parliament 

 for Aberdeen and a member of the recent Liberal Ministry, as 

 professor of civil law in the University of Oxford, as a careful and 

 conscientious student of history, and as an accurate and painstak- 

 ing man of affairs, whose knowledge of America is extraordinarily 

 full and accurate. Professor Bryce combines in himself both the 

 knowledge and the temper necessary to write a treatise on Ameri- 



