All of the rocks exposed at Smugglers Notch ([Figure 10]) are the mica-albite-quartz schist which locally contains garnet. The large rock boulders in the Notch were derived from the cliffs forming the walls of the Notch. The gradual processes of weathering and breaking up by freezing cause large slabs of the rock to become loose and eventually break off the cliff faces to careen down the mountainside to the valley below, just as King Rock did within historical time. At the north end of the Notch, the large accumulations of such boulders form a talus slope, the name for rock accumulations at the base of a cliff. The irregular stacking of these rocks have formed Smugglers Cave. Smaller openings extend further back under the “rock pile” to where the ground is considerably colder and where the heavier cold air has sunk. Drafts of this air escaping at the foot of the talus is noticeably cool.
The Smuggler’s Face, Elephants Head, the Singing Bird, and the Hunter and His Dog are freaks of nature and a product of man’s imagination. Their existence is due to the haphazard nature in which the rocks on the cliff faces have broken along joint surfaces.
The origin of the Notch is not completely known. The steep walls and the narrowness of the Notch suggest that it could not have been formed by the headward erosion of two streams or by glacial action. It seems most likely that it was formed by the erosive action of an ancient river that once flowed through the area. Because of the high elevation, the only time when such a river could have existed is when the Champlain Valley was filled with ice on the west side of Mount Mansfield, so that the normal drainage of water to the west was blocked by the ice. It is possible that the conditions were such that the water supplied by the melting glacier could only drain to the south through the Notch. After the ice retreated the drainage system was abandoned in favor of lower outlets and eventually the drainage was developed to Lake Champlain in the west. The Notch was modified by the headward erosion of the present small streams. Except for the shape of the Notch, the only evidence for this hypothesis is the occurrence of a weakly-bedded, well-sorted deposit of sand at the north end of the Notch at an elevation of 2050 feet. Such a deposit of sand is characteristic of standing water, which occurring at this elevation indicates that some vastly different drainage system must have existed in the past.
Figure 9. The Chin and Bear Head on Mount Mansfield viewed from Sterling Pond.
Figure 10. View of Smugglers Notch and Spruce Peak from ski slope on Mount Mansfield.
Big Spring
On the south side of the Smugglers Notch road at an elevation of about 1800 feet is the Big Spring which furnishes a tremendous output of cold spring water. The source of the water is not known although it is likely that, like most springs, it is derived from an underground drainage system. The spring probably originates by the seepage of water derived from the winter snows and rainfall in Spruce Mountain through a joint system within the mountain. No buried stream channels could be located between the spring and the base of the massive overhead cliffs. The belief that the spring is related to Sterling Pond is unfounded. It is unlikely that surplus water could be drained from Sterling Pond because it already maintains a delicate balance between the supply of water from rain and snow and the output to the stream flowing to the north.