TOURNAL OF GEOLOGY 
MAY-JUNE, 1902 
THE DEVELOPMENT OF SYSTEMATIC PETROGRAPHY 
IN THE NINETEENTH CENTURY. 
CONTENTS. 
Part [.—INTRODUCTION. 
VIEWS OF RocKs BEFORE THE NINETEENTH CENTURY. 
Linnzeus; Development of mineralogy; Foundations of petrography; Werner’s 
classification of rock formations. 
DEVELOPMENT OF SYSTEMS IN THE NINETEENTH CENTURY. 
Abbé R. J. Haiiy, 1801; John Pinkerton, 1811; Alexandre Brongniart, 1813; 
P. L. A. Cordier, 1815; John Macculloch, 1822; Karl Czsar von Leonhard 
1823; Alexandre Brongniart, 1827 ; Systems of von Leonhard and Brongniart 
compared. 
Investigations into the Chemical Composition of Rocks; Classification by 
Feldspars ; Influence of genetic hypotheses ; Geological classifications. 
Carl Friedrich Naumann, 1850, 1858; Bernhard von Cotta, 1855, 1862; Ferdi- 
nand Senft, 1857; J. Reinhard Blum, 1860; Justus Roth, 1861; Th. Scheerer, 
1864; Ferdinand Zirkel, 1866; Ferdinand von Richthofen, 1868. 
Cordier’s System and its Influence; H. Coquand, 1858; Archibald Geikie, 1872, 
Part f.—Beginning of the Microscopical Era; Ferdinand Zirkel, 1873; A. von 
Lasaulx, 1875; H. Rosenbusch, 1877; Foqué and Michel Lévy, 1879. 
™An abstract.of this review was delivered as.a retiring presidential address before 
the Geological Society of Washington, December, 1900. 
Vol. X, No. 4. 331 
