THE OLD RED SANDSTONE. 203 
from base to summit with birch, hazel, and hawthorn, we 
find the passage shut up by a perpendicular wall of rock 
about thirty feet in height, over which the stream precipitates 
itself, in a slender column of foam, into a dark, mossy basin. 
The long arms of an intermingled clump of birches and ha- 
zels stretch half way across, tripling with their shade the ap- 
parent depth of the pool, and heightening in an equal ratio 
the white flicker of the cascade, and the effect of the bright 
patches of foam which, flung from the rock, incessantly 
1evolve on the eddy. 
Mark now the geology of the ravine. For about half way 
froin where it opens to the shore, to where the path is ob- 
structed by the deep mossy pool and the cascade, its precip- 
itous sides consist of three bars or stories. There is first, 
reckoning from the stream upwards, a broad bar of pale red; 
then a broad bar of pale lead color; last and highest, a broad 
bar of pale yellow; and above all, there rises a steep green 
slope, that continues its ascent till it gains the top of the 
ridge. The middle, lead-colored bar is an ichthyolite bed, a 
place of sepulture among the rocks, where the dead lie by 
myriads. ‘The yellow bar above isa thick bed of saliferous 
sandstone. We may see the projections on which the sun has 
beat most powerfully covered with a white crust of salt; and 
it may be deemed worthy of remark, in connection with the 
circumstance, that its shelves and crannies are richer in vege- 
tation than those of the other bars. The pale red bar below 
is composed of a coarser and harder sandstone, which forms 
an upper moiety of the arenaceous portion of the great con- 
glomerate. Now mark, further, that on reaching a midway 
point between the beach and the cascade, this triple-barred 
line of precipices abruptly terminates, and a line of preci- 
pices of coarse conglomerate as abruptly begins. I occa- 
