Knoxville journal. [volume] (Knoxville, Iowa) 1874-1986, 1875-09-02

=. .he cnrrrut number Of the Ocerl0nd
. fssS;tnrrix eecIogist reviews the geoiogi-
al friklence of the antiquity OF human
ss--ierafrsf near the present town oil Cnero.
-. II th.s State, and estimates the age Oh
Is - r,,,Sf ANCIENT of discovered towns 10
- NIT less than $50 900 years The data
~ al ~uch calculations are necessarily
uncertain, ~ they are derived rom .us
present MOTORS of me conunch's aa ~.
nrrseu, rairs CT erosion; still, from the
changes that have taken place since 'ne
pioneers of prehistoric California iei' iheil
traces on lis sacicn, sea-shore, there can
be no doubt that thousands OF centuries
must have come and gone.
The traces in question are numerous
stone rortars. found in undistnrpen
white and yellow gravel OF suhaqueons
formation, not fuviatile, underlying the
vast sheets of volcanic rock OF winch
Table Mountain is part In one instance
. mortar was found standing upright,
with the pestle in il, apparently just as II
had been leff by its owner. In some cases
the rnortars have been found at the deptn
of forty feet from the surface of the gravel
underlying Table Mountain. The distri-
button OF the morta1s is such as to indi.
cate with great positiyeness the former
existence of human settlement on that
ancient beach when the water stood near
the level at which they occur g tine an
terror 10 the volcanic outpouring which
Table Mountain records, and anterior 70
the glacial epoch.
The recent geological history OF that
region may be briefly summed as ioI-
lows: Previous to the placing OF the
mortars in the position In which they
have been found, the early and
middle tertiary sea level had receded to
the position of the coal beds underlying
Table Mountain, fully 1000 feet below the
level Of Cherokee. Subsequently, IN the
pliocene period, there was further subsi-
dence of about | 500 feet, something like
600 feet occurring after the mortars had
been abandoned. All this, as has been
noticed, took place before the volcanic out
flows which covered up all the ancient
detritus Of the region, including that of the
ancient rivers Whose graveis have fur
nished so much of the gold OF California;.
The geological age of the river period was
determined by Lesqucreux from specimens
Of vegetation, now extinct, collected IN tle
survey of the ancient rivers; specimens in.
dicating fora Of the pliocene age, re-
tanning some characteristic miocene form
After the volcanic period the land rose
again, the time Of emergence embracing
the glacial period and the new eroding
period In the sierra, during which the
States and the hard metamorphic green
stones and the GRANTEES were slashed with
canons 3 900 feet deep by the action of ice
and running water. Taking the rates OF
continental movement determined by Lyell,
our geologist calculates, that the time re
quired for the changes thus outlined could
not have been less than 1880 centuries.
For period so long preceding the glacial
epoch as the time when ancient Cherokee
was buried by the waters Of the advancing
sea, his estimate is certainly not extrava-
CANT, though ii does transcend so enor.
mously the time men have been accus-
toned TO allow for mans residence on
earth.