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Indiana University Studies 



10 feet in width, and reaches back under the sandstone to 

 the east. This opening is sHghtly higher than the openings 

 to the south, but perhaps less than 5 feet higher. The flood 

 water comes out of this opening with great velocity. The 

 opening has a perimeter composed entirely of sandstone, a 

 rather interesting occurrence, showing that it must have beer- 

 developed along a combined joint and bedding plane, and 

 under pressure from the water within. It is not known how 

 far back one would be able to crawl into the opening, but it 

 is likely that one would come to the passageway, or a series 

 of passageways, along the joints of the Beech Creek lime- 



l^'K.. '.>. Tlu' flood-water outlet df the water trom tlie ■"Aiiiericaii Bot- 

 toms" basin. Tliis opening has its perimeter entirely in tlie Cypress sand- 

 stone. 



stone within a few yards or a few hundred feet of the opening, 

 after a descent of not more than 10 or 12 feet. 



As indicated by the topographic map, the ''American Bot- 

 toms" for the most part is a basin, and furthermore a basin 

 with holes in it thru which the water escapes. The 675-foot 

 contour line is the highest depression contour, and encloses 

 approximately 1,475 acres, or 2 5/16 square miles. The area 

 enclosed by this contour line has a total perimeter of approxi- 

 mately 18 miles. The lake waters were probably much nearer 

 the 650-foot contour line. It may be noted here that some 

 beautiful beach lines are preserved at an elevation of about 



