GROWTH OP MINERALOGY 275 



System of Mineralogy started in this way in 1837, has 

 continued by means of successive editions to be the stand- 

 ard reference book in the subject. The various editions 

 appeared as follows: I, 1837; II, 1844; III, 1850; 

 IV, 1854; V, 1868; VI, 1892 (by Edward S. Dana). 



J. D. Dana also contributed numerous mineralogical 

 articles to the first series of volumes of the Journal. 

 It is interesting to note that they are chiefly concerned 

 with the more theoretical aspects of the subject, in fact 

 they constitute practically the only articles of such a 

 character that appeared during this period. Among the 

 subjects treated were crystallographic symbols, forma- 

 tion of twin crystals, pseudomorphism, origin of minerals 

 in metamorphosed limestones, origin of serpentine, 

 classification of minerals, etc. 



The volumes of the Second Series of the Journal cov- 

 ered the years from 1846 through 1870. This period was 

 characterized by great activity in the study of the chem- 

 ical composition of minerals. A number of skilled 

 chemists, notably J. Lawrence Smith, George J. Brush 

 and Frederick A. Genth, began about 1850 a long series 

 of chemical investigations of American minerals. Very 

 few articles during this time paid much attention to the 

 physical properties of the minerals under discussion, 

 practically no description of optical characters was 

 attempted, and only occasionally were the crystals of a 

 mineral mentioned. J. D. Dana was almost the only 

 writer who constantly endeavored to discover the funda- 

 mental characters and relationships in minerals. He 

 published many articles in these years which were con- 

 cerned chiefly with the classification and grouping of 

 minerals, with similarities in the crystal forms of dif- 

 ferent species, with relations between chemical compo- 

 sition and crystal form, chemical formulas, mineral 

 nomenclature, etc. The following titles give an idea of 

 the character of the more important series of articles by 

 him which belong to this category: On the isomorphism 

 and atomic volume of some minerals (9, 220, 1850) ; vari- 

 ous notes and articles on homo2omorphism of minerals 

 (17, 85, 86, 210, 430; 18, 35, 131, 1854) ; on a connection 

 between crystalline form and chemical constitution, with 

 some inferences therefrom (44, 89, 252, 398, 1867). 



