LITERARY NOTICES. 



561 



volve, indeed, some of the most radical 

 problems of popular government. Wo 

 have been told that the price of liberty 

 is eternal vigilance, and the truth is 

 far more pregnant than is generally 

 supposed. But we require to learn a 

 still more elementary lesson, that is, 

 what liberty is. Our common notion 

 of slavery has come to be negroes sold 

 at auction, and our notion of liberty has 

 come to be the privilege of locomotion 

 and of voting. A people with such no- 

 tions of the subject will hardly be very 

 vigilant in paying tlie price of liberty 

 by strenuously resisting all encroach- 

 ments upon individual rights. There- 

 fore, every discussion which makes the 

 subject clearer, and calls attention to 

 considerations which are apt to be gen- 

 erally overlooked and forgotten, is im- 

 portant ; and nowhere is it more impor- 

 tant to guard against the indifference of 

 citizens and the fallacies by which they 

 are misled on the subject of liberty 

 than where government is popularly 

 administered. Mr. Spencer's future pa- 

 pers will probably bear much more di- 

 rectly upon American political prob- 

 lems than the present. 



LITERARY NOTICES. 



World - Life ; or, Comparative Geology. 

 By Alexander Winchell, LL. D., Pro- 

 fessor of Geology and Paleontology in 

 the University of Michigan. Chicago : 

 S. C. Griggs & Co. Pp. 642. Price, 

 $2.50. 



In this compact but comprehensive book 

 Professor Winchell has made a contribution 

 to science that was greatly needed, and he 

 has performed his task in a manner that 

 well comports with the grandeur of the sub- 

 ject. A carefully prepared book, represent- 

 ing the present state of knowledge on " the 

 processes of world-formation, world-growth, 

 and world-decadence," has been urgently 

 needed for some years. There is, no doubt, 

 much shallow skepticism in many minds re- 

 garding the validity of inquiries in this field, 

 which has been relegated to the sphere of 

 scientific romance and fanciful speculation. 

 But sober and well-instructed minds have 

 VOL. XXIV. — 36 



not shared in this feeling. Our knowledge 

 concerning the genesis of worlds is, of 

 course, yet very incomplete, and there is 

 necessarily much of that divergence of opin- 

 ion in relation to it which always belongs to 

 the stage of active advancing imjuiry. But 

 there is already a great body of assured and 

 formulated knowledge bearing upon the 

 problem of the genesis of worlds which is 

 not to be gainsaid, and there has been the 

 steadily increasing necessity that this knowl- 

 edge should be collated, and organized into 

 definite scientific form. But a somewhat 

 special preparation was required to do any- 

 thing like tolerable justice to this work. 

 The factors of the discussion are of the 

 largest import. Celestial mechanics has 

 long been the fundamental element of the 

 research, and within recent years celestial 

 chemistry has come forward as of equal im- 

 portance. Nebular cosmogony and nebular 

 evolution are now established conceptions 

 of science, and, in working them out, the 

 sciences of geology and astronomy are of 

 equal significance and application. Profess- 

 or Winchell refers to his task as an attempt 

 at " laying the foundations of a science 

 which, from one point of view, may be 

 styled the geology of the stars, and, fromi 

 another, the astronomy of the earth. It is 

 the science of comparative geology. It is 

 astrogeology." In regard to the present 

 position of the nebular view, the author re- 

 marks : " Nor can it be correctly said that 

 the general theory remains still in the status 

 of an hypothesis. In certain points of de- 

 tail opinion may still remain divided ; but, 

 when an hypothesis has stood the scrutiny of 

 three generations, and has become all but 

 unanimously accepted, by those prepared to 

 form original opinions, as the real expres- 

 sion of a method in nature, surely, then, the 

 time has passed when any person can ad- 

 vantageously illustrate his learning and sa- 

 gacity by continuing to reproach the con- 

 ception as ' a mere hypothesis.' If any 

 ' mere hypothesis ' ever strengthened into 

 the condition of a scientific doctrine, as- 

 suredly we find in the scientific world to- 

 day the general features of a sound nebular 

 doctrine." 



Professor Winchell's geological studies, 

 long carried on in connection with the coe- 

 mical problems which they involve, have well 



