MINERALS AND ORES 



173 



FIG. 86. IN THE CAVE OF THE WINDS, MANITOU, COLORADO 



This cave has been made in limestone rock by water which has trickled 

 through and dissolved the calcium carbonate. 1. What name is given to 

 the hanging masses? 2. How are the masses on the floor formed? 3. In 

 what respect, beside form, do they differ from thp roof and sides of the 



through limestone, it dissolves some of the rock, leaving 

 crevices and sometimes large caverns. Later, as the water 

 trickles through the roofs of such caverns, some of the water 

 evaporates and leaves limestone pendants of crystallized cal- 

 cite, hanging like icicles from the roof. The falling drops 

 leave on the floor a deposit of limestone which gradually 

 accumulates and makes a little mound. The pendants are 

 stalactites, and the mounds are stalagmites. They extend 

 toward each other, until they meet and gradually form a 



