252 IN MAMMOTH CAVE 



at a hundred yards it was still quickly percep- 

 tible, but broader and higher; it had begun to 

 lose some of its coldness, and to mingle with 

 the general air; all the plants growing on the 

 margin of the watercourse were in motion, as 

 well as the leaves on the low branches of the 

 trees near by. Gradually this cool current was 

 dissipated and lost in the warmth of the day. 



