288 The A?nerica?l Geoloj^ist. November, 1899 
the second or eleven-foot terrace their distribution is somewhat 
different. At one place near the edge of the plain, close to a 
known vein of white quartz, one foot in thickness, under the 
present water level, the soil for a length of forty feet and ex- 
tending back from the edge of the bank at some places to 
fifteen or more feet, is closely packed with quartz fragments, 
nearly all of small size, as though flaked off in making arrows. 
They appear to be confined to the upper six inches of the soil, 
and are well exposed by a prospector's shaft and a number of 
smaller excavations. Many of the pieces show evidence of 
concussion and pressure, but there was nothing in the least 
resembling an implement. They are not of the ordinary fiake 
shape like the chert fragments from quarry sites in Illinois and 
Missouri, but are very irregular in form, although quite angu- 
lar and fresh-appearing, and in one case showing, I think, 
the effects of pressure applied slowly and for a purpose. 
The following apparent differences between the quartz on 
the low'er terrace and these on the Glacial plain were observed: 
The quartz wdien freshly quarried has a faint bluish tint and a 
very slightly translucent lustre. All the fragments discovered 
in the soil of the Modern flood-plain preserve this appearance 
of freshness. But, on the upper plain, the quartzes, although 
equally as transparent, seem to have lost the bluish tinting 
and somewhat of the translucency, so that they have a more 
ancient appearance. They are very widely distributed, some- 
what uniformly, on the upper plain, and there also appear to 
penetrate into the subsoil, while on the Modern flood-plain 
they are found only in pockets or bunches in the surface soil 
near the outcrops of the quartz or along the river bank. These 
pockets contain much larger quantities of fragments than those 
on the upper plain, but are more compacted, and hence occupy 
less space. The evidence, fragmentary although it is, suggests 
that the age of the quartz distribution on the flood-plain is not 
the same as that on the Glacial terrace. 
The verv wide distribution of small quartz fragments on 
the sand plain may suggest that they are not of artificial origin. 
1 have looked into this question somewhat closely, and have 
concluded that to no other agency than human can be attri- 
buted their transportation to their present positions. They 
occur usuallv in a fine-grained, sandy soil, almost free from 
