Reviews. 



Manual of Determinative Mineralogy , zvith an hitroduction o?i Bloiv- 

 pipe Analysis. By George J. Brush. Revised and enlarged 

 by Samuel L. Penfield. New York : John Wiley & Sons, 

 1896. 



Since its first appearance in 1874, ^xnsW?, Defennijiative Mineralogy 

 and Blowpipe Analysis has filled the demand for a text-book in this 

 science almost to the exclusion of others. The tables, especially, 

 proved to furnish an exceptionally ready and accurate means of iden- 

 tifying mineral species. The use of the book has of late years, how- 

 ever, been confined largely to the tables,, since its opening chapters, 

 while valuable for reference, were hardly adapted for class instruction, 

 if, indeed, they were intended to be so used. This lack in the book 

 Professor Penfield has most satisfactorily filled in the new form in 

 which he now presents it. In its present form it furnishes not only a 

 complete text-book for class use, but also a work which should enable 

 even the novice without further aid to gain a practical knowledge of 

 determinative mineralogy. 



Opening with a statement of the chemical principles especially 

 applicable to mineralogy, for the author remarks that mineralogy is 

 chiefly a chemical science, the next chapter treats, with excellent illus- 

 trations, of the apparatus and reagents to be employed and of the nature 

 and uses of flames. Several new experiments incorporated here add 

 much to the value and interest of the chapter. 



In the following chapter the reactions of the elements, arranged in 

 alphabetical order, are given with great fullness, while carefully described 

 experiments show how many of the typical reactions can be obtained. 

 Every detail is here given with a care and precision that might at first 

 sight seem superfluous, but the necessity for each. Professor Penfield, 

 it may be believed, has fully proved in his long experience as a 

 teacher of the subject. The student will at least be impressed with the 

 need of care and accuracy in making the tests and will not be led to 



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