THE MAMMOTH CAVE. 203 
that, in the formation of a stalactite, a period 
of fifty years is required to produce an incrusta- 
tion of the thickness of a wafer. We have not 
attempted to calculate the time necessary, at 
this rate, to form a stalactite of the size named. 
Geologists, in estimating the antiquity of the 
origin of the earth, might find important data 
here that, to our knowledge, has not been here- 
tofore used. But it would be impossible to ap- 
proximate accuracy in such calculations, from 
the fact that it may have been, for all we know, 
twenty thousand years since the cessation of the 
process of formation, for this appears to be one 
of the oldest avenues in the Cave. 
To the ceiling of the Chapel are attached 
great numbers of small stalactites, from six to 
eighteen inches in length, giving a very singular 
and handsome view overhead. 
The Gothic Chapel has been very accurately 
and strikingly photographed by the parties be- 
fore mentioned. 
Speaking of the immense stalactites found in 
Gothic Chapel, reminds us that we have not ex- 
plained the meaning of the terms “ stalactite” 
and “stalagmite,’ which formations being pecu- | 
liar to caves, it is presumed that the majority of 
readers are not familiar with the process of their 
