Across coveted lands : or, A journey from Flushing (Holland) to Calcutta, overland . ^ . , I , Mushroom Sand Hill . Sand Accamalation (jg^jr pj^p^n ^rroded by Wind i Water)on Mountain 5) Serai sphericalSand Mound. Pyramidicalsand Side carrodedby Sand. 5and Barchans. Sand Hili,.s. 5and-Mill with one Sidecorroded by Wind. XXX BARCHANS 319 primary obstacle, however small, arresting thesand. Various are the theories with regard tothe formation of these barchans, and especiallywith regard to the formation of the hollow onthe lee side. The explanation from my own observation has—if no o
Across coveted lands : or, A journey from Flushing (Holland) to Calcutta, overland . ^ . , I , Mushroom Sand Hill . Sand Accamalation (jg^jr pj^p^n ^rroded by Wind i Water)on Mountain 5) Serai sphericalSand Mound. Pyramidicalsand Side carrodedby Sand. 5and Barchans. Sand Hili,.s. 5and-Mill with one Sidecorroded by Wind. XXX BARCHANS 319 primary obstacle, however small, arresting thesand. Various are the theories with regard tothe formation of these barchans, and especiallywith regard to the formation of the hollow onthe lee side. The explanation from my own observation has—if no other—at least the merit of wind, on meeting the semi-circular back ofthe barchan, is diverted on the two sides of it;these two currents come into violent collisionagain on the lee-side, where, the air being moreor less still, a considerable portion of the wind isforcibly driven back towards the barchan, cor-roding its side in a double rotatory way, eachsuch circle having for a diameter the radius ofthe barchan crescent containing them. In factin many barchans the sand ripples on the wind- Direction ^of Wind. ~^^
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectirandescriptionandtr
