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GLACIAL MAN IN THE TRENTON GRAVELS.
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forming correct opinions upon the subject, held pretty much the same views of Dr. Abbott's finds.

To make the above criticism entirely clear, a few words of explanation of talus phenomena may be added. As a river cuts its channel deeper and deeper into deposits of gravel a section is gradually exposed, but the gravels break down readily under

Fig. 4.A freshly formed gravel bluff.
Fig. 5.Early stage of talus formation.
Fig. 6.An ancient talus.

atmospheric influences and the exposed face does not retain a high angle. The upper part crumbles and descends toward the base, there to rest against the slope or to be carried away by the stream. A supposititious case will be convenient for illustration. A gravel terrace twenty feet in height is encroached upon by the

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