312 Exploring Visits to the Sources of the Hudson. 
On the 4th we once more resumed the ascent of the main stream, 
proceeding first in an easterly direction, and then to the southeast 
and south, over falls and rapids, till we arrived at the head of 
the Great Dyke Falls. Calcedony was found by Prof. Emmons 
near the foot of these falls. Continuing our course on a more grad- 
ual rise, we soon entered upon unexplored ground, and about three 
miles from camp, arrived at the South Elbow, where the bed of 
the main stream changes to a northeasterly direction, at the point 
where it receives a tributary which enters from south-southwest, 
Following the former course, we had now fairly entered the High 
Valley which separates Mount McMartin from the High Peak on 
the southeast, but so deeply enveloped were we in the deep growth 
of forest, that no sight of the peaks could be obtained. About a 
mile from the South Elbow we found another tributary entering 
from south-southeast, apparently from a mountain ravine which 
borders the High Peak on the west. Some beautifully opalescent 
specimens of the Labradorite were found in the bed of this stream. 
High Valley of the Hudson. ‘ 
Another mile of our course brought us to a smaller tributary from 
the north, which from the alluvial character of the land near its 
entrance is called the High Meadow fork. ‘This portion of our 
rout is in the center of this mountain valley, and has the extraordi- 
nary elevation of three thousand and seven hundred feet above tide. 
We continued the same general course for another mile, with our 
rout frequently crossed by small falls and cascades, when we emerg- 
ed from the broader part of the valley and our course now became 
east-southeast and southeast, with a steeper ascent and higher and 
more frequent falls in the stream. ‘The declivity of the mountain 
which incloses the valley on the north and that of the great peak, 
here approximate closely to each other, and the valley assumes 
more nearly the character of a ravine or pass between two moun- 
tains, with an increasing ascent, and maintains its course for two or 
three miles, to the summit of the pass. Having accomplished more 
than half the ascent of this pass we made our camp for the night, 
which threatened to be uncommonly cold and caused our axemen 
to place in requisition some venerable specimens of the white birch 
which surrounded our encampment, 
