272 



SCIENCE. 



[Vol. XII. Na 305 



SCIENCE 



A WEEKLY NEWSPAPER OF ALL THE ARTS AND SCIENCES, 



PUBLISHED BY 



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Vol. XII. 



NEW YORK, Dec. 7, 18 



No. 305. 



CONTENTS: 



Scientific News in Washington. 



The Soaring of Birds 



Human Beasts of Burden 



A Queer Game among the Navajo 



Electrical News. 



The Use of Condensers in distribut- 

 ing Electricity 



The Action ot Electricity on the 

 Vesicles of Condensed Steam 



Commelin, Desmazures. and Ba-'l- 



hache Storage-Battery 269 



u. Trj:„„ .T-i -Lighting Sys- 





The Edi; 



tem in Berlin. 



The Eickemeyer Dynamo. . . 

 Trial of an Electnc Locomot 

 ninghamj Engl; 



270 



Electric- Lighting 270 



An Electric Surface Road in New 



York . . . 270 



Commercial Geography. 



The Obi Railroad 271 



Notes and News 271 



Editorial 272 



Book- Reviews. 



A Brief History of Greek Philos- 



Paradoxes of a Philistine 



The Critical Period of American 

 History 



Astronomy with an Opera-Glass. . . 



America!^ Weather 



The Writer's Handbook 



The Death-Blow to Spii itualism. . . 



Among the Publishers . . 



Letters t*" the Editor. 



The great extent of forests in the State of New York, 

 and their devastation, that has been going on continuously, have 

 led to repeated endeavors to protect them from unlawful cutting- 

 down and wasteful practices. For this purpose the New York 

 State Forestry Association was founded in 1885, and did much to 

 get the well-known forestry law passed by the Legislature. Since 

 that time, however, the association has failed to show a vigorous 

 life. At present renewed endeavors are being made to establish 

 the association as a working body for the purpose of disseminating 

 knowledge on the importance of forests, and for promoting meas- 

 ures to secure their proper protection. The New York Academy 

 of Sciences devoted its meeting last Monday to this subject ; and 

 the proposed steps, which were explained by Professor Southwick 

 of the New York State Forestry Association, found general in- 

 dorsement in the discussion following Professor Southwick's re- 

 marks. The object is one of great economic importance to the 

 State, and, as Dr. H. Nicholas Jarchow, the first speaker of the 

 evening, remarked, the forests forming a portion of the public do- 

 main ought to be a source of considerable income instead of causing 

 expense. He continued, " It would be very advantageous to estab- 

 Ush a forestry school in or near the Adirondacks. Its cost would 

 not be large, especially if adjoining States, having much the same 

 climate and varieties of trees, would combine to support a school. 



Moreover, the labors of the students would nearly pay e,xpenses, 

 and, once graduated, there would be a demand for their services 

 from all parts of the country. Congress has made a national rec- 

 ommendation on the subject ; but Congress is slow to act, and the 

 States should provide for themselves in the matter. Trained for- 

 esters would take an honest pride in their work, and put their 

 hearts in it. They would save valuable lumber, prevent great 

 thefts of timber, and break up the present state of affairs, with all 

 its disadvantages." Experience has shown that the last act of the 

 Legislature, although a step in the right direction, has not the de- 

 sired effect : therefore all measures taken for inducing the Legisla- 

 ture to organize a good forestry board, with ample means for car- 

 rying on its important work, and attempts to spread an intelligent 

 knowledge of the importance of forests and of their economic 

 value, must be highly welcomed. The New York Academy of 

 Sciences has done well to bring the subject once more before the 

 public, and it is to be hoped that the meeting will be of help to the 

 attempted re-organization of the State Forestry Association. 



BOOK-REVIEWS. 



A Short Account of- the History of Matheynatics. By WALTER 

 W. R. Ball. London and New York, Macmillan. 12°. 

 $2.60. 



Mr. Ball, who is a fellow and assistant tutor of Trinity Col- 

 lege, Cambridge, offers in this compact volume a transcript of his 

 lectures delivered in the spring of the present year on the history of 

 mathematics. While technical and exact enough to be of value to 

 the specialist in mathematics as a handy book of reference, it is so 

 clearly and familiarly written, that it is the best work on this sub- 

 ject for the general reader that we know of. 



The region of mathematics is a terra incognita to most persons, 

 even those who consider themselves possessed of a good general 

 education ; and this, despite the fact that mathematics as a mental 

 discipline is unsurpassed, and is unrivalled for the beauty and 

 grandeur of its results. Having for its foundation the two universal 

 and necessary forms of perception, space and time, mathematics 

 developed, naturally enough, in the early stages of reflective 

 thought. To trace the growth of its conceptions in clearness and 

 perspicuity, and to follow up the increasingly complex and varied 

 forms of symbolism, is the work of the history of the science, and 

 Mr. Ball's treatment of it is eminently successful. 



After a summary notice of what we may call the prehistoric pe- 

 riod of the science, mathematics as understood and taught by the 

 Egyptians and Phoenicians, the author makes a tripartite division of 

 the subject, — mathematics under Greek influence, the mathematics 

 of the middle ages and the renaissance, and modern mathematics. 

 Of the first period, Pythagoras, Euclid, Archimedes, and Ptolemy are 

 the most important representatives. The qiiadriviuin of the medi- 

 aeval schools is traced back to the division of knowledge adopted 

 by the Pythagorians, — numbers absolute, or arithmetic ; numbers 

 applied, or music ; magnitudes at rest, or geometry ; magnitudes in 

 motion, or astronomy. In a chapter on ' Systems of Numeration,' 

 after the prominent names in this first period have been discussed 

 in chronological order, Mr. Ball gives an interesting account of the 

 early methods of counting, and the introduction of the abacus. In 

 his mention of the use of this instrument, we should have been glad 

 to find a more extended notice of the form of it in use among the 

 Chinese, and some further explanation of the very complicated com- 

 putations which they perform by its aid with great celerity and ac- 

 curacy. 



In the second period, most of the mathematicians were astrono- 

 mers ; but the period includes the introduction of Arabian mathe- 

 matical works and the results of Arabian thought into Europe. In 

 reference to this, Mr. Ball says, " It was from Spain, and not from 

 Arabia, that Arabian mathematics came into western Europe. 

 The Moors had established their rule in Spain in 747, and by the 

 tenth or eleventh century had attained a high degree of civilization. 

 Though their political relations with the caliphs at Bagdad were 

 somewhat unfriendly, they gave a ready welcome to the works of 

 the great Arabian mathematicians. In this way the Arab transla- 



