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PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Apr. 1, 



late the curve due to the whole body, a few simple groins would 

 have sufficed for all their purposes. It is precisely the same question 

 as if it were proposed to make a 10-inch pendulum beat seconds, or 

 one 39 inches long beat once in two seconds. It can be done by 

 main force, but the moment the pressure is removed or weakened the 

 pendulums resume their natural beat ; and a clockmaker who con- 

 structed his clocks on this principle would fail as certainly as the 

 Austrian engineers. 



3. Elevation of the Banks of Rivers. — The second point to which 

 I wish to call attention is the tendency of rivers in alluvial soils, 

 especially in deltas, to raise their banks, and so confine themselves 

 in their beds. 



This process has been well described by Sir Gardner Wilkinson 

 as regards the Nile, and by Sir Charles Lyell for the Mississippi ; but 

 neither of these gentlemen appear to me quite to have caught, or at 

 least explained, the true cause. As regards the Ganges certainly, 

 and the other rivers so far as I can judge, it is owing to the existence 

 of great sheets of still water in the low lands beyond the banks of 

 the rivers. These, being still, have deposited their mud, if they ever 

 had any in suspension ; and being too massive to be set in motion by 

 the rivers, they reduce the flowing streams to inaction the moment 



2000 feet ; the average length of oscillation 8500 or 4 # 25. The slope about 

 6 inches per mile. The following Table gives the approximate extent of the 

 oscillation of the Granges and the three Kishnaghur rivers. 





Distance, 



direct, 

 in miles, 



Distance, 

 per river, 

 in miles. 



Width of 

 stream, 



low water, 



dry season, 



in feet. 



Number of 

 oscilla- 

 tions. 



Length of 

 oscillation, 

 in miles. 



Ganges. 



62 

 80 

 74 

 82 

 96 

 90 

 30 

 32 



96 

 24 

 34 



50 



18 

 30 

 24 



104 



113 



96 



106 



108 



100 



44 



36 



120 

 30 



42 



112 



28 

 50 

 29 



3500 

 4000 

 5000 

 6000 

 7000 

 7000 

 4000 

 3000 



1200 

 2000 

 3000 



1000 



1500 

 800 

 500 



17 

 20 

 15 



11* 



10 



10 

 6 



8 



62 



9 



11 



42 



9 

 46 



47 



3-7 



4- 



5- 



7- 



9-5 



9- 



5- 



4- 



1-5 

 2-5 

 3- 



1-2 



2- 



a 



3 



2. 

 2 



Buxar to Patna 





Rajmahal to Rajapore 



Ua j apore to Pubna 



Pubna to Jaffiergunge 



Bhagaruttee. 

 Ch okah to Nuddya 





Choedah to Calcutta 



Jellingiiy. 



Matabangaii. 



Coomar to Kissingunge ... 

 Kissingunge to Chogdah ... 



