Miscellaneous Intelligence. 199 



4. The Evolution of Worlds ; by Percival Lowell. Pp» 

 xiii, 262. New York (The Macmillan Co.). — This book is a 

 revised edition of lectures delivered in February and March, 1909, 

 before the Massachusetts Institute of Technology, in which 

 institution the author is non-resident professor of astronomy. 

 The lectures present the most recent facts and speculations 

 regarding the past and future of the Solar system, illumined by 

 the play of the author's active imagination and colored by an 

 astonishing vividness of language. We do not remember to 

 have met in any of Dr. Lowell's previous essays any such free- 

 dom in the use of English. Some of the theories which he 

 explains are startling, but the language in which they are set 

 forth is much more so. If we all permitted ourselves such 

 liberties with our mother tongue it would speedily descend to a 

 chaos and darkness such as Dr. Lowell predicts for the solar 

 system itself. 



We quote at random from the first few pages. 



"Unimpressing our senses," "grandiose vicissitudes spectrally 

 revealed," "stars cuticle," "ambidextrous impartiality of space," 

 "The culmination of Coalition" — "the acme of accretion." 



But such mishandling of language, though it irritates the reader 

 and mars his enjoyment, does not vitiate the logic or destroy 

 the substance of the book. 



The first two chapters, entitled " Birth of a Solar System," and 

 " Evidences of the Initial Catastrophy," will excite most interest. 

 The author considers that the initial stage of our solar system, or 

 rather the beginning of the cycle of change through which it is 

 now passing, was that of a spiral nebula.- From this the present 

 order arose and to it in some distant age and region it may again 

 return, to repeat the cycle indefinitely. Such an enormous pro- 

 gram, which explains everything but the origin of matter and 

 provides for its eternal activity, satisfies the mind and makes us 

 wishful that it may be true. 



Space forbids a discussion of it further than to say that the 

 spiral form in a nebula is held to be due to action from without 

 rather than from within, in fact to a tidal disruption caused by 

 the passage of a large body close to the previously quiescent 

 mass. Thus an old and worn out sun may be torn up within a 

 few days into a meteoric nebula, heated by collisions of its frag- 

 ments and developing nnder gravity into a planetary system. 



w. B. 



5. Hyperbolic Functions, prepared by George F. Becker 

 and C. E. Van Orstrand. Pp. li, "321. Smithsonian Mathemat- 

 ical Tables, No. 1871. Washington, 1909. — In the systematic 

 study of mathematics hyperbolic functions do not receive the 

 attention which their practical importance as a tool of investiga- 

 tion warrants. Invented or first employed by Mercator in the 

 development of his system of projection, on which to this day all 

 deep sea navigation depends, they have come to play an important 

 part in many branches of applied mathematics. Thus in physics 

 whenever an active entity is extinguished or absorbed (e. g. light, 

 velocity, radio-activity) the decay is represented by some form of 



