Geology 



hardened they were placed in small metal boxes, one of 

 which was handed to each member of the party, who 

 also carried a supply of ordinary tallow candles in a tin 

 box. Matches thus treated are quite waterproof, and 

 may be easily struck on coarse sand-paper or on a rough 

 rock surface even after a prolonged immersion in water. 



Having arrived at the end of the ledge we lighted a 

 torch, embarked in our canoe and paddled up the stream. 

 As our eyes became accustomed to the gloom we found 

 that we were traversing a stream which filled the cave 

 from side to side. The roof was flat and some 20 

 feet above the level of the water. It was covered by 

 lines of stalactites which were semi-transparent and 

 about 3 to 4 inches in length, being of the thickness 

 of a piece of wheat straw. One set of these lines 

 ran parallel to the length of the cave, while the other 

 set traversed the roof nearly at right angles to the first. 



On more careful examination these lines were found 

 to be those of cracks or joints in the limestone roof 

 through which water was slowly oozing. Farther on 

 the roof became much lower, and we had to sit in the 

 canoe in a stooping position to prevent our heads coming 

 into contact with the roof. This was a good oppor- 

 tunity for studying at close quarters the small stalactites, 

 which are produced as follows. A drop of water forms 

 on the line of one of the cracks and gradually increases 

 in size. During this process, owing to the evaporation 

 of some of the water, or perhaps to the escape of some 

 of the carbonic acid, a thin film of carbonate of lime is 

 found covering the surface of the drop. Eventually the 

 drop falls, carrying with it the greater part of the film, 

 but a small part remains attached to the roof in the 



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