8o The American Geologist. February, i904. 
specks of gold, while the hornblende has become disintegrated 
to some extent into chlorite ; quartz-schist of a dark grayish 
shade and medium sized grains ; talcose schist, weathering al- 
most black, but on fracture readily showing the characteristic 
lustre and the greasy feel of talc; hornblende-schist of dark 
green shades, showing veinlets of quartz running parallel to the 
schistosity of the rock ; black flint, the break of which exhibits 
the characteristic concoidal surface ; milk quartz and yellowish 
brown quartz, partly coated by lime ; very brittle, soft shaly 
limestone of light color, showing impressions of shells, which 
could not, however, be identified ; argillaceous sandstone, easily 
breaking into thin slabs, of gray color and occasionally tinged 
by iron oxide ; light gray argillaceous shale, at places colored 
by iron oxide, possibly a phase of thel ast ; light yellowish finely 
stratified clayey sand, exhibiting concretions of iron oxide and 
clayey casts of probably vegetable matter. 
From the drift, exposed in the banks of Beaver creek, may 
be noted : cobblestones of the size of a hen's egg of gray granite 
with medium quartz grains and feldspar crystals of nearly equal 
size; nevadyte (granitoid rhyolyte) of a yellowish gray, carry- 
ing garnet (spessartite?) ; fine grained granitoid rock, speckled 
all over with minute dots of iron oxide ; hornblende-granite 
with pink orthoclastic feldspar crystals , holding iron oxide : 
pinkish quartzyte of very firm texture ; black flint, exhibiting 
conchoidal fracture ; yellowish quartz ; magnesian limestone, 
more or less crystalline, showing on yellowish-brown surface 
cross-sections of crinoid stems and fragments of heads ; some- 
what compact clay, highly charged with iron sesquioxide ; black 
shaly coal, containing cylindrical hollows probably previously 
occupied by roots and rootlets. 
Pebbles have been noted of medium grained granite with 
pink feldspar crystals and abundant mica, the granite show- 
ing lighter and darker phases ; andesyte ; syenyte. the horn- 
blende of which has become changed into chlorite, while the 
orthoclase is in phenocrysts ; fine grained gneiss of dark color ; 
gray quartzyte ; hornblende-schist ; chlorite-schist ; dark brown 
flint, with conchoidal fracture; dark augite-dioryte with dirty 
white and pink plagioclase crystals, quartz of various shades ; 
whitish chalkstone, probably Niobrara. 
The coarser material of the drift shows at many places a 
coating of finer detritus, cemented together by calcium carbon- 
