742 A. W. (IRABAU INTEKPRKTATION OK SEDlMExNTAKY HOCKS 



evident that much wurk along seashores is still necessary before we <;ri 

 hope to do more than approximate in our attempts at interpretation. 



The Older Continental Deposits 



The case is less desperate when we adventure upon the continent, for 

 here we have already a wealth of data gathered with especial intent to 

 serve as a basis for interpretation, though it must be confessed that very 

 much remains to be accomplished. And since Walther and the physiog- 

 raphers have shown us the way, a fair amount of interpretational work of 

 the older continental deposits has been attempted. Strange to say, some 

 of the earliest contributions along this line were made by geologists from 

 the British Isles, that stronghold of marine conservatism. That Medli- 

 cott and Blanford should, in the late '70's, interpret the Siwalik forma- 

 tion of India as a sub-recent fiuviatile example, is readily enough under- 

 stood, for they had before them the Indo-Gangetic plain in process of 

 formation, the deposits of which were identical with that of the upturned 

 Tertiary of the sub-Himalayan region. But that British rocks should 

 by Britishers be interpreted as continental formations is more remarkable. 

 Perhaps as canny Scotsmen, Mackie and Goodchild were more likely to 

 dissent from the prevailing English view, just as Hugh Miller was perhaps 

 the first to suggest the fresh-water origin of the Old Red Sandstone, in 

 his day a heresy which was duly quashed by the imperious Murchison. 

 Mackie and Goodchild twenty years ago gave evidence pointing to the fiu- 

 viatile and seolian origin of the Old Red Sandstone and the existence of 

 desert conditions in Britain, and Lomas followed ten years later with a 

 discussion of desert conditions during the formation of the British Trias. 

 During Walther's visit to Scotland he apparently convinced Peach and 

 Home of the subaerial origin of the Old Red and Torridon sandstones, 

 and so brought into the camp of the continentalists two men, than whom 

 none have a more intimate knowledge of, or speak with greater authority 

 on, the older rocks of Scotland. 



That Walther should find many disciples in Germany was, of course, to 

 be expected, though those who know the temper of the German scientists 

 will not be surprised to find that he was perhaps more violently opposed 

 in his own land than elsewhere. But today the younger geologists of 

 Germany ardently pursue "Sediment-Petrographie," and in Germany a^ 

 well as in France lithogenesis of sediments is a live study. 



In America the recognition of older continental deposits is of more 

 recent date. W. D. Matthew, in 1899, discussed the possible aeolian orighi 

 of the White River beds, and Davis, in 1900, interpreted the Rocky Moun- 



