1884. ] Topographical Phenomena in Indiana. 371 
rains the water percolates through these cracks, rendering the 
cubes soft and slimy, and aiding the plastic slide in the direction 
of the dip of the cube cracks—southward. 
In support of the theory I advance—well, call it speculation— 
I submit the following facts: -If a lump of putty, say twenty-five 
pounds, with a consistency that would maintain its shape, should 
have a number of small sticks or common matches stuck into it 
in an erect position, as shown by the dotted line in Fig. 1, these 
would represent trees growing on a hillside. If one side of this 
putty should be exposed to the heat of the sun or a fire, its con- 
sistency would be reduced and it would slide as shown by the 
solid line in Fig. 1, and the matches (trees) would lean down hill. 
Fic. I. 
‘ The trees always grow vertical unless inclined by some exte- 
Nor force. On hillsides we find the young trees growing verti- 
cally, inclining down hill with age, the oldest inclining most. 
Without doubt the old trees started in life with good intentions, 
and tried to grow with the plumb line. When a tree is suddenly 
inclined as much as forty-five degrees, it will send out saplings 
from the upper side of its trunk. See tree 4 in Fig. 2, which 
figure illustrates the different slope of north and south-facing hills 
in the glacial drift, and the lean of the trees thereon. 
_ Fig. 3 shows the profile of a railroad survey north and south, 
ma crossing east or west streams and ravines in the drift 
Fi 
et 4 shows the lean the trees would take at the bends 
Pha bottom as indicated by the arrows, and the slope of the 
wie north and south side of east and west flowing streams 
Tavines in the drift region. _ 
