198 



PEOCEEDnSTGS OF THE GEOLOGICAL SOCIETY. 



cleaner coarser sand, and last of all dirty fine sand again, — all de- 

 posited in the course of a few hours, and this in a river having a 

 velocity of 6 feet a second and more. This to my mind proves that 

 flowing water, once it has got its proper load, cannot cut the bed below. 

 Therefore, to carry a constant load, there requires to be a constant 

 velocity where the depth is uniform. The third and last is to show 

 that the beds of our large rivers are rising rather than being lowered, 

 however slow this process may be. This, to the engineer, is a most 

 satisfactory conclusion to arrive at ; for he knows he has only to 

 guard against local scour and not a general depression of the beds 

 of rivers passing through alluvial plains. 



Table of Soil met with in boring the Artesian Well at UmbaUa. 



Total 

 depth. 



Clay. 



Sand. 



\/Lixed. 



Remarks. 



4 



4 









6 





2 





Firm sand. 



9 



3 







Clayey soil. 



11§ 





2i 





Fine sand. 



26^ 



i's 







Two beds ; upper 3| feet very stiiF. 



27 



• •■ 





'"i 



Stiff brown clay mixed with kunkur. 



41 





14 





Fine sand ; water-bearing at 32 feet. 



50 



"9 







Three beds ; lower, 5^ feet, brown clay, and 



53* 





"k 





above this 2 feet of blue clay. 



56| 



"3 









67 



... 



m 







69 



2 









80 





11 







85 



5 









86^ 





1* 







122 



351 





... 



Very stiff brown clay. 



124 



... 





2 



Kunkur formation. 



128 





"4 







137 





... 



9 



Mixture of sand and clay. 



139 





2 







144 







5 



Mixture of sand and clay. 



148 





"4 







150i 



... 





2i 



Kunkur-bearing stratum. 



154 





"k 







166 



12 







Dark red clay. 



174 





"s 





Two beds, with 1 inch of shaly formation. 



180 



"6 









181i 







H 



Kunkur-bearing stratum ; on getting through 

 this, the water rose suddenly 40 feet, and 



183 



... 



n 





in two hours to 70 feet. 



184i 







n 



Kunkur-bearing stratum. 



196 





114 





Two beds ; lower, 6 feet, coarse sand. Pres- 



196i 



1 

 -5 







sure exerted on tubes 20 tons ; tempera- 



199 





2i 





ture of water 78°. 



202| 







H 



Clay with kunkur. » 



211 





"h 







212 







1 



Dark red clay with kunkur. 



213 



"i 









214i 







1* 



Sand and clay with kunkur. 



220| 







6 



Clay with kunkur, with black spots. 



