700 Vestiges of Glacial Man in Minnescta, [July, 
_ sissippi finally withdrew permanently from the terrace-plain, and 
cutting out a lower bed for itself in the drift alluvium, formed the 
existing terrace-bank, it would naturally leave the quartz stratum 
what we find it to-day. That is, the western border having been 
cut off and swept away, the western limits of the remainder would 
preserve a general thickness uniform with that of the central por- 
tion, or nearly so. 
During a copious and long-continued rainfall in the summer of 
1881, the roadway leading through the notch was at one time 
washed out at its point of emergence and westward to a depth of 
four or five feet below the quartz stratum. The lower portion of 
the newly exposed surface was then seen to be stuck full of quartz 
chips intermingled with occasional quartz implements. These 
seemed to be vestiges of a former westward prolongation of the 
quartz-bearing stratum. An irregular block of quartz, from eight 
to twelve inches in dimension, was here found impacted in the 
stone rubbish at the top of the till. This is remarkable as being 
the only lump of quartz larger than a club-head ever encountered 
among the thousands taken from the place. The block was 
white, sharply angular, and wholly unwaterworn; it was associ- 
ated with subangular and rounded stones which had no other 
visible unwaterworn fragments among them; and it had, stil 
adhering to certain of its planes, foliations of some other mineral 
of so soft a nature that the blocks would inevitably have yielded 
to attrition had it ever been subjected thereto. Every a 
indicated that this was a mass which had been used t ae 
pieces from for further manipulation. It was imbedded among 
quartz bits and implements before mentioned. These were strewn 
about in the utmost confusion, being wedged into th ; 
bish at every imaginable angle. Many of the latter specimens, 
unlike those from the stratum, were more or less defaced, gai 
small, long bits nicked out of the surface. Among them r ch 
some few objects which belonged to stratum types; but w 
were nevertheless waterworn. 
Third : certain of the quartzes of the stratum 
arranged upon the floor of deposit in little rudely 
or groups of objects of some one particular type: 
sentative fact or two will very likely afford a clearer 
case than can otherwise be had, a few illustrative 
offered here. During the autumn of 1879, upon the 
o strike 
e stone rub- 
have been distinctly 
assorted heaps 
Asa 
view of the 
details ar 
day whee 
ree Riana? Seok aa oe 
Se 
ep ere eee 
