H1YSIOGRAPHICAL GEOLOGY. 185 



Independently of the Americans, the writings of Sir Andrew 

 Ramsay, and of Sir Archibald Geikie and Professor James 

 Geikie in Scotland, gave convincing evidence of the work of 

 ice and water upon the rocks. Riitimeyer contributed in 

 Switzerland a brilliant paper on the formation of valleys, while 

 Desor elucidated the leading features of desert and moraine 

 landscapes, and his teaching found able followers in Heim, 

 Baltzer, Fellenberg, Du Pasquier, and Penck. De Lapparent 

 and De Margerie in France, Torell and Helland in Scandinavia, 

 Muschketow and Lewakowsky in Russia, are the leaders in this 

 direction of study. 



In 1869, Oscar Peschel had collected the principles of physio- 

 graphical geology into a systematic form, and thus given the 

 first incentive towards converting the study of this subject into 

 an independent scientific discipline. Instead of the earlier 

 formal grouping of the surface- forms, the treatment of the 

 subject now betokened an effort to group together all types of 

 form which have a similar genetic history. What Peschel tried 

 to initiate in this direction was fully realised by Baron von 

 Richthofen in his book, Fuhrer jiir Forschungsreisende (Berlin, 

 1886). This work, designed primarily as a guide in the 

 methods of observation, is based for the most part upon the 

 personal observations of the author during many years of travel 

 in the Alps, Carpathians, North America, and China, and has 

 become in Germany the standard work for the systematic treat- 

 ment of surface-forms. 



In 1894, Penck accomplished the difficult task of arrang- 

 ing our present knowledge of surface-configuration upon the 

 basis of leading genetic principles. In his Morphologic der 

 Erdoberfldche^ Penck has presented the chief results of the 

 special literature of physiography in clear, concise form. A 

 comparison of Richthofen's Fuhrer and Penck's Morphologic 

 with the older works on orography and hydrography, shows 

 very plainly the great improvement that has been effected by 

 the new methods of study in the domain of geography. 



