Feb. 1901. Observations on Indiana Caves — Farrington. 263 



Fig. 



as it is at right angles to 

 the wall. Observation 

 of the broken end of 

 any of the "leaves" of 

 such a group of stalac- 

 tites will show the man- 

 ner of growth. (See 

 Fig. 8.) Such growths 

 are not formed by water 

 trickling down a crevice, 

 but from currents de- 

 bouching over a lime- 

 stone sheff. The shelf 

 must project slightly 

 and the current of water 

 must be relatively large. 

 There are first formed 

 stalactites of the ordi- 

 nary conical type. Then 

 deposition is confined 

 only to one side of the 

 stalactite, the side, 

 namely, over which the 

 descending water flows. 

 Growth takes place then 

 almost wholly in this 

 A deposit is, however, also 



-Eroded Stalactite. Shiloh Cave. 

 (Mus. No. G.881). 



direction and in the direction of length 

 built up from the surface of the shelf by the water flowing over it. 

 So the mass grows upward in a thin layer, downward at the 

 stalactite points and outward in thin sheets at right angles to the 

 cave wall. There is also a slight lateral growth of the stalactites 

 which causes them in time to join one another, and the group thus 

 acquires the appearance of a continuous sheet thrown into folds. 

 The original stalactite points usually continue to be the points of 

 greatest growth in length, but the stalactite may be longest some 

 distance away from these. Corrugations of the surface showing 

 retardations of the flowing waters, and similar to those so common 

 on icicles, are nearly always present. If the current is compara- 

 tively narrow and maintains its position for a long period of time the 

 stalactitic mass will take a semi-circular form owing to the fact that 

 the portions in the center of the current receive more material than 



