844 



Walcott ^) has assumed an average yearly denudation of 1 foot 

 in 10000 years or about 0,03 mm. per annum, stating at the 

 same time that the maximal annual denudation was then held- to 

 be 1.5 mm. (1 foot per 200 years). This maximum is even sur- 

 passed by the Seraju, Djragung and Pengaron ; the average rate of 

 denudation, admitted by geologists, is surpassed some times by the 

 Tjiliwong, in whose system the clastation of rocks proceeds much 

 more slowly than is the case with some other Java-rivers that have 

 been examined. 



1) C. D. Walcott, Journ. of Geology. I. Chicago. 1893. Quoted from E. Dacque. 

 Grundlagen der Palaeogeographie. Jena 1915. 



