632 



SCIENCE. 



[N. S. Vol. II. No. 45. 



sliall endeavor in the next chapter to explain 

 these laws and to show how they may be illus- 

 trated by the simple cases of motion already 

 discussed ; we then go on to assume them as 

 true always and to deduce their consequences 

 in other cases." By way of proper caution he 

 adds, however, that " We shall not now discuss 

 the question whether these fundamental prin- 

 ciples were stated in their best form by New- 

 ton. Our present object is to give a consistent 

 account of the Science of Mechanics as it has 

 been developed from Newton's laws." 



The following chapters VI-VIII are de- 

 voted to the consideration of Newton's laws of 

 motion and the consequences deducible there- 

 from. The presentation of these matters is 

 admirable and must take rank with that given 

 in the best works hitherto published. Indeed, 

 though the book professes to be elementary 

 only, its exposition of these matters appears to 

 be as luminous and complete as can be given 

 without the aid of the calculus. 



The last three chapters deal with cvirvilinear 

 motion of a particle under gravity, collision of 

 masses, and motion of a particle in a circle re- 

 spectively. The book has many well chosen 

 illustrative examples, whose answers are given 

 in most, though, properly, not in all cases. 

 There are a few samples of examination ques- 

 tions given, and the book terminates with a 

 good index. 



The faults of the work, if any may be fairly 

 urged against it, are faults of omission rather 

 than of commission. The only one which seems 

 worthy of mention is the absence of an explana- 

 tion and a use of the theory of the dimensions of 

 the units which figure iu mechanical quantities. 

 Nothing, we believe, helps more to fix ideas 

 with regard to the terms force, momentum, 

 energy, etc. , in mechanics than a knowledge of 

 that theory, while its application is of great aid 

 to the student in detecting and in correcting 

 his blunders. An application of this theory, 

 for example, will immediately detect the mis- 

 print in the formula on p. 187 of the book ; 

 though it is but just to add that this is the only 

 misprint which that theory has disclosed iu our 

 reading of the book. We may express the 

 hope that future editions of this capital work 

 will be improved by the addition of an appen- 



dix explaining the doctrine of units and dimen- 

 sions of units in mechanical quantities and in- 

 dicating the great utility of the doctrine to 

 students and investigators. 



E. S. WOODWAED. 



Fourteenth Annual Report of- the United States 

 Geological Survey to the Secretary of the In- 

 terior, 1892-93. By J. W. PowELL, Director. 

 Part I. Report of the Director. Part II. 

 Geology — accompanying papers (Vignette). 

 Washington, Government Printing Office. 

 1893. 8°, 2v. 



Volume I., of 321 pages, is taken up by the 

 administrative reports of heads of divisions 

 and by other executive matters. The only gen- 

 eral interest that it possesses lies in the fact that 

 it sets forth the plans and policies of the Director 

 and of the above officials. The second volume 

 contains a valuable series of accompanying 

 papers, viz: 



1. Potable Waters of the Eastern United 

 States, W J McGee, pp. 5-47. 



2. Natural Mineral Waters of the United 

 States, A. C. Peale, pp. 53-88. 



3. Results of Stream Measurements, F. H. 

 Newell, pp. 95-155. 



4. The Laccolitic Mountain Groups of Colo- 

 rado, Utah and Arizona, Whitman Cross, pp. 

 165-241. 



5. The Gold-Silver Veins of Ophir, California, 

 Waldemar Lindgren, pp. 249-284. 



6. Geology of the Catoctin Belt, Arthur 

 Keith, pp. 293-395. 



7. Tertiary Revolution in the Topography of 

 the Pacific Coast, J. S. Diller, pp. 403-434. 



8. The Rocks of the Sierra Nevada, H. W. 

 Turner, pp. 441-495. 



9. Pre-Cambrian Igneous Rocks of the Unkar 

 Terrane, Grand Canyon of the Colorado, Ari- 

 zona, Charles D. Walcott, with notes on the 

 Petrographic Character of the Lavas, by Joseph 

 Paxson Iddings, pp. 503-525. 



10. On the Structure of the Ridge between 

 the Taconic and Green Mountain Ranges in 

 Vermont, T. Nelson Dale, pp. 531-549. 



11. On the Structure of Monument Mountain 

 in Great Barrington, Mass., T. Nelson Dale, 

 pp. 557-565. 



12. The Potomac and Roaring Creek Coal 



