!?«••■ 



346 Review of Alger^s Phillips^ Mineralogy, 



This discovery sets in a strong light the importance of making 

 the optical properties of minerals, the subject of inquiry in deci- 

 ding on identity, when from the nature of the case the evidence 

 can be obtained. 



We regret that this subject has been so summarily treated in 

 these three works. 



We might easily extend these remarks, for many things of mi- 

 nor importance are passed over without notice. Our object is not 

 to undervalue Mr. Alger's labors, which we esteem highly, and we 

 take pleasure in assuring the student of mineralogy, that he can- 

 not open the book without finding much to reward him for his 

 perusal. The adoption of false and antiquated principles of clas- 

 sification, leading to absurdity in some cases, and the want of a 

 discriminating courage in the rejection of bad and doubtful spe- 

 cies, are its most prominent faults. 



Had Mr. Phillips lived to this day, he would not we are sure 

 have retained the divisions of the science which were current in 

 England when he wrote, and although we will not pretend to say 

 that he would have followed either Mohs or Necker, or any other 

 modern author, it is certain he would not have closed his eyes to 

 the beautiful natural relations of species, which have been point- 

 ed out by the progress of mineralogical science during the last 

 ten years. 



But we must hasten to say a few words relative to the " Trea- 

 tise" by Prof. Shepard. This is a second edition of the first part 

 of the treatise by the same author, published in 1832, with some 

 additional information comprised in the table of species. The 

 classes and orders of Mohs are retained, but there is no division 

 into genera. 



" While so much uncertainty exists relative to many of the species, 

 and while such different views are likely to prevail respecting the gen- 

 era, the application of a systematic nomenclature to minerals can scarce- 

 ly be received with approbation. Indeed it has thus far been met with 

 decided tokens of discouragement, not only, as might have been expect- 

 ed, from learners, but from the more experienced cultivators of the study. 

 An additional reason for its disuse appears to be, that the number of spe- 

 cies in the mineral kingdom is so small, that the memory requires less 

 artificial help to retain a distinct conception of the relations of the spe- 

 cies, than in the departments of zoology and botany, where the cases 

 are not few in which a single order contains several times as many spe- 



