5 8 EDWARD M. SHEPARD 



The earth on the shores [of the Mississippi River] opened in wide fissures, closing 

 again, and water and mud, in huge jets, were thrown higher than the treetops. 



The atmosphere was filled with a thick vapor or gas The sulphurous 



gases discharged during the shocks tainted the air, and the river water, for 150 

 miles below, could not be used for a number of days. 



Hon. Lewis F. Linn, of the United States Senate, states in a 

 letter concerning this earthquake that "the earth rocked to and fro, 

 vast chasms opened from which issued columns of water, sand, and 

 coal, accompanied by hissing sounds." 1 



To sum up the testimony of most observers, we have emphasized 

 the fact that the disturbance came from the west; that the ground 

 rolled in great waves; that numerous fissures were formed; that 

 great volumes of "sulphurous vapors," water, sand, and lignite were 

 thrown up at various heights; that large areas were covered with 

 water, the subsidence of which was marked by a thick coating of 

 sand; that these shocks continued for nearly three years; and that 

 the waters of the Mississippi receded for several minutes. 



Further, we find today that large volumes of water are constantly 

 coming to the surface as springs in this district; that these springs 

 are numerous along the lines of fissure; that deep artesian wells 

 around this region bring up this same variety of sand with lignite, 

 some, as at Memphis, when first sunk, ejecting large chunks of the 

 lignite; that the sand and lignite brought up in the deep wells are 

 similar to the same substances brought up by the innumerable springs 

 that feed the lakes and streams of this district, and that they are 

 apparently the same as that which surrounds the blow-holes and 

 fault scarps, and which covers, as with a vast sheet, the considerable 

 areas in the sunken district. 



Relation 0} the earthquake to artesian conditions. — If one studies 

 the phenomena of the earthquake as seen by the observers quoted 

 in this article, he cannot help being impressed with the fact that the 

 conditions as described are identical with what would be expected 

 to occur from the undermining of the clay horizon by the slow and 

 continuous removal of large bodies of sand. In this process of under- 

 mining a time would come when a slight disturbance would destroy 



1 The above quotations are taken from Dr. Broadhead's collection of letters 

 and documents relating to the earthquake, published in the American Geologist for 

 August, T.902. 



