228 BULLETIN OF THE 



must be some connection with the creek, either directly or back through the 

 rocks. The lake is the place to catch the fish in high water. It is accessible, 

 if one does not count the ' gumbo,' which makes an almost impassable sticky 

 covering over the entire floor of the cave. This ' gumbo ' forms the banks of the 

 stream. It is difficult to keep one's footing there. With all our care it was 

 constantly falling into the stream, roiling the water and scaring the crayfish. 

 There was a small, dark-colored salamander near them. I brought home only 

 one small fish and four small crayfish, the largest about two inches long. But 

 I am much encouraged, for I feel sure that in time we can get all you want, 

 and I realize there is ever so much that I can learn. ^ 



Samples of the "gumbo," or red mud, of the floors of the caves 

 were sent with the collection. Experiments with it proved its excessive 

 fineness and stickiness. Stirred about in the water at a depth only 

 of two and a half inches, it was more than three hours before it had 

 settled so that objects could be distinguished on the bottom. Twenty- 

 four hours later, a cloudy substance, an inch and a half in depth, seemed 

 to bang over the bottom, and it was more than two days before it had 

 completely settled. 



Miss Hoppin's first work was done in August ; in September she 

 made further efforts. In answer to questions, she states that the wells 

 from which specimens have been taken are about half a mile from 

 Centre Creek, the water level in wells and creek being nearly the 

 same. The wells were nine or ten in number, from five to eighty rods 

 apart, from eleven to thirty feet in depth, deeper in the higher ground, 

 and having a depth of water varying from two to four feet. In some 

 wells the rock at the bottom had been excavated. The water is what 

 is commonly called hard, i. e. impregnated with lime. After rains, some 

 of the wells have softer water than others, and the water stands higher 

 in these wells, indicating closer connection with surface drainage. All 

 the wells soon regain the common level. They become low in times 

 of drouth, but never dry out entirely, as is the case with a cave spring 

 near by, about twelve feet above the level of the creek. The tempera- 

 tures taken in the wells at low water ranged from -j-52° to 54° Fah- 

 renheit. During a storm, in the well having the highest water the tem- 

 perature rose to -{-57°. When the mercury stood at 90° to 95° in the 

 shade outside, the temperature was only 54° in Wilson's cave. 



" After several days of a cold wave, the night temperature of the outer air 

 being 45° and the noon reading at 60° to 70° in the shade, I found the tem- 

 perature of the water in the cave had gone down about two degrees. . . . 

 The level of this cave is ten or more feet above the creek, and it is not affected 



