, 



4 



>i% 





ral 









■tree I 



hlflit 



• 



rer 

 the 



is 



w 



up 





Ch. XIX.] 



MUD-LUMPS OF THE MISSISSIPPI. 



451 



So much carburetted hydrogen or inflammable 



gas 



pours. 



is emitted together with salt or brackish water, that Col. 



Fig. 35. 





S.S.W. View of the Mud-lump called the Wart, N.E. Pass 



Extreme height above low water, 14 feet. 



Sidell suggests that they deserve the name of 

 rather than of springs. The tubular cavities up which the 

 springs rise are about 6 inches in diameter, vertical and as 



One which, was 



gas 



vents 



form 



sounded was found to be 24 feet deep, and the lead at the 

 bottom of the line seemed to be still slowly sinking through. 



thick mud. 



first from 



highest part, and afterwards successively through cracks at 

 lower and lower levels, and in some " 

 they have altogether ceased to flow. 



lumps 



Duri 



storms, when the surface of the gulf is raised by the 

 prevalence of certain winds, the salt water is blown into the 



mud 



liie steepness and occasional verticality of the sides in the 



denudi 



mg action. Hun 



Lump (figs. 34, and 35) are due to such 



away an entire mud-lump, or at least such portions of it 



G G 2 



as 



