558 



THE POPULAR SCIENCE MONTHLY. 



springs from the absence of a natural and 

 rational system of classification, such as 

 long since was introduced in the organic 

 worlds. Not that attempts at this needed 

 classification have been wanting. Two ri- 

 val schools for many years have contended 

 for methods diametrically opposed. The 

 so-called natural-history or mineralogical 

 method was advocated by Werner, Mohs, 

 Jameson, Shepard, and Breithaupt ; the 

 chemical method, as formulated by Berze- 

 lius and developed by Rammelsberg, has 

 been the basis of the text-books of Phil- 

 lips, Dana, and Naumann. The possibility 

 of reconciling these apparently antagonistic 

 systems has been the aim of our author 

 throughout his long career of study. La- 

 bors in this direction, which from time to 

 time have been brought to the attention of 

 the scientific world, are in the present vol- 

 ume connected and completed, formin"' what 

 he terms a natural system of classification. 

 He approaches his main task by a presenta- 

 tion of those elementary principles of chem- 

 istry and physics which underlie alike the two 

 rival methods hitherto in the field. He dis- 

 cusses the nature of chemical combination, 

 of which he holds that solution is a phase ; 

 the periodic law ; and the important prob- 

 lem of ascertaining the relative degree of 

 chemical condensation, upon which depends 

 the varying hardness and insolubility of spe- 

 cies. Between the physical characteristics 

 and the chemical constitution of a mineral 

 subsist necessary relations ; on these rest 

 the new classification, in which the seeming 

 contradictions of the two rival schools are 

 brought to accord. In place of the old 

 trivial names we are given a classic Latin 

 nomenclature for classes, orders, genera, 

 and species — that for species being bino- 

 mial. This system realizes, in a simplified 

 form, that projected by Breithaupt and left 

 unfinished by him. An examination of his 

 nomenclature, as well as of those proposed 

 by Mohs and by Dana, is followed by a sy- 

 nopsis of native species, with both their 

 scientific and trivial names. This is suc- 

 ceeded by a critical discussion of the more 

 important genera and species. In his two 

 concluding chapters Dr. Hunt presents orig- 

 inal and striking views of the genesis of 

 carbonaceous minerals — graphite, diamond, 

 petroleum, and coal ; and, further, upon the 



mineral history of natural waters. In his 

 preface our author announces his intention 

 of preparing a descriptive mineralogy based 

 upon this new classification. 



Schliemann's Excavations: An Arch^o- 



LOGICAL AND HISTORICAL StUDY. By 



Dr. C. ScHucHAKDT. Translated from 

 the German by Eugenie Sellers. New 

 York : Macmillan & Co. Pp. 863, with 

 Plates. Price, $4. 



The author of this book is Director of 

 the Kestner Museum in Hanover. His pur- 

 pose in writing it has been to present the 

 results of Schliemann's Excavations in a 

 concise form, which should make them more 

 accessible to the general public ; and the 

 work appears to have been undertaken with 

 the sanction of the discoverer. He has 

 also sought, by careful discussion and com- 

 parisons, to find what are the ascertained 

 results, and to present them free from the 

 conjectures and enthusiastic speculations 

 with which Schliemann's first reports, from 

 the nature of the conditions under which 

 they were written, are necessarily encum- 

 bered. The author was engaged in Grecian 

 archjeological excavation at Pergamos when 

 he was intrusted with the preparation of the 

 work. He improved the opportunity he then 

 had of making personal observations on the 

 spot, and of informing himself by inter- 

 course with the persons concerned. The 

 undertaking was a difficult one, for the ques- 

 tions which Dr. Schliemann's activity had 

 called up are still undecided, and additions 

 to our knowledge on the subject are con- 

 stantly furnished by further excavations. 

 But it was pleasant, for these objective 

 studies in Greek antiquity have a charm 

 that is surpassed in no other pursuit. In 

 the account of Troy the history is given of 

 the controversy of the two rival sites, the 

 topography is compared with the references 

 in the Iliad, and the reasons are given — all 

 in seventy-five pages — for believing conclu- 

 sively that Homer's Troy was real and 

 Schliemann's identification of it is correct. 

 Tiryns is described, in forty pages, as af- 

 fording the most ancient illustrations of the 

 civilization of which Mycenoe has furnished 

 so numerous and so splendid examples. 

 The largest space is given to Mycenae, with 

 its remarkable tomb-structures and treasure- 

 chambers, and its truly astounding richness 



