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fact, the floor of the forest is characteristically devoid of 
vegetation, a feature shown by other forests of hemlock 
situated further north. The contrast in passing from the 
hemlock woods to the contiguous hardwood area which 
borders them to the west and north, toward the museum 
building and the herbaceous grounds, is at once apparent, 
for here we see a luxuriant growth of shrubs and of herbs, 
including many of our most interesting wild flowers. 
11. The Gorge of the Bronx River 
The gorge of the Bronx River extends from the boulder 
bridge at the north end of the hemlock forest southward 
for about a mile, nearly to Pelham Avenue, and is a most 
beautiful and picturesque natural feature, besides being of 
great geological significance. Its depth from the summits 
of the hills on both sides averages nearly 75 feet, and its 
sides below the foot-bridge at the mansion are nearly ver- 
tical rock faces. The hills on both sides are heavily wooded 
with hemlock spruces and other trees. In the upper part 
of the gorge the Bronx flows slowly, being held back by the 
dam forming the water-fall at the mansion, and the ele- 
vation of its surface is only a few inches higher at the 
boulder bridge, than it is at the fall; after plunging over the 
dam, however, the river runs in its unobstructed natural 
channel with all the appearance of a mountain stream, 
which at high water is exceedingly beautiful. 
12. North Meadows and River Woods 
The Bronx River enters the northern end of the Garden 
from Williamsbridge and flows as a slow stream southward 
to the water-fall at the mansion, its surface being nearly 
level throughout this distance. It is spanned just inside 
the northern boundary of the Garden by a concrete-steel 
arched bridge with granite copings, which carries the main 
park driveway across it near the Newell Avenue entrance. 
The entire northern end of the Garden is formed of the 
flood plain of the Bronx River, consisting largely of grassy 
