VIEWS ON MINERAL SPECIES. 433 



MODERN NATURAL HISTORICAL SYSTEMS. 



To revive recollections of the old Natural History 

 System at the close of the century may seem to be an 

 unprofitable exhumation of buried feuds, but there are two 

 reasons why it should be far from superfluous. In the first 

 place the system is not really dead, and it expresses certain 

 truths and relations which are in themselves permanent ; in 

 the second place a reaction against the classification of Rose, 

 that is to say, against a chemical classification as commonly 

 understood, has been in progress for some years, and the 

 tendency of the present changes and of the future develop- 

 ments, of which they are the precursors, can best be read 

 in the light of this past history. 



Mohs, who succeeded Werner at Freiberg, was him- 

 self succeeded by Breithaupt, who retained all the traditions 

 of the Natural History School of Mineralogy in this great 

 centre of mining industry and education ; and his successor, 

 the present occupant of the chair, Dr. Albin Weisbach, has 

 never forsaken the system. 



The Synopsis Mineralogica of Weisbach (1884) divides 

 minerals into four classes : hydrolyte or soluble compounds, 

 lithe or stones, metallolithe, metalhte or ores, and causte or 

 inflammable compounds. The three minerals chosen above 

 for examples belong to the second of these classes which is 

 divided into three orders : Kuphoxyde or oxides, Pyritite or 

 silicates, and Apyritite or non-silicates. 



The order Pyritite is subdivided into four families : 

 Sklerite, Zeolite, Phyllite and Amorphite ; Garnet, Felspar 

 and Scapolite belong to the first of these families, in which 

 the various mineral species are arranged according to their 

 crystallographic systems. 



Possibly few English mineralogists are aware that this 

 antiquated type of classification is still in vogue ; its adop- 

 tion at the great mining centre invests this system with a 

 stamp of authority in spite of any objections which may be 

 urged against it from a purely scientific point of view. A 

 classification which, for example, not only separates Apatite 

 from Pyromorphite, and Chalybite from Calcite, but even 



