Reviews — E. Dana's Mineralogy. 571 



I thought it well to place this find in Fermanagh upon record in 

 the proceedings of the British Association, and I shall be happy to 

 report to the Association next year the results of the cave-digging 

 which I am carrying on here at present. 



IR E "V I IE AA7" S. 



I. — A Text-Book op Mineralogy, with an Extended Treatise 

 ON Crystallography and Physical Mineralogy. By Edward 

 Salisbury Dana. New Edition, entirely rewritten and enlarged. 

 8vo; pp. 593, with nearly 1,000 Figures and a Coloured Plate. 

 (New York: John Wiley & Sons, 1898.) 



BY the irony of Fate the author of this treatise, Mr. E. S. Dana, 

 though an experienced mineralogist, is a University Professor, 

 not of Mineralogy, but of Physics ; those who have been his pupils 

 report him to be an ideal teacher of that branch of knowledge : 

 further. Mi-. Dana prepared for press the last edition (1892) of his 

 father's well-known " System of Mineralogy," a book which is in. 

 constant use by mineralogists throughout the world. An excellent 

 teacher and closely associated with Mineralogy as a living science, 

 Mr. Dana was thus particularly qualified to furnish the Students of 

 Minerals with a good text-book of their subject, and he has done so. 



The work was first issued twenty-one years ago : the author has 

 now rewritten it with the results of recent researches in mind. 

 Part I (144: pages) deals with Crystallography in a practical way, 

 demanding from the student only the elements of mathematical 

 science. The subject is treated from the point of view of Symmetry, 

 and the thirty-two classes of symmetry are briefly but clearly 

 explained ; the name assigned to each of the prominent classes 

 being taken from some mineral species, of which the crystals 

 present good illustrations of the class of symmetry. The facial 

 symbols are those of Miller, and stereographic projection is made 

 extensive use of. Part II (94 pages) treats of Physical Mineralogy 

 in a similarly elementary way, and necessarily deals for the most 

 part with the characters which depend upon Light, and with the 

 modes of their determination. " Axes of optical elasticity " are 

 dropped, and the "Indicatrix" is explained and made use of in 

 the discussion of doubly-refracting crystals. Part III, Chemical 

 Mineralogy, is compressed into 30 pages, and is limited to the 

 explanation of the general principles of Chemistry and of the modes 

 of chemical determination of minerals. The last Part, Descriptive 

 Mineralogy, extending to 225 pages, is not susceptible of much 

 variation of treatment, but is accurate and brought up well to date. 

 The book is plentifully illustrated throughout. 



We may assume that so completely changed an Edition is 

 evidence of the recovery of the author from the shattered health 

 to which he had been brought by the years of toil required by 

 the preparation of the last edition of the " System of Mineralogy " ; 



. ! 



