The Jersey City news., 1903-05-29
JERSEY GLACIERS
Big BoWlders Shifted About
Many Centuries
Ago.
"a GEOLOGICAL TALE
Study of the "Drift" In the
Northern Parts of the
State.



you vii see a huge bowlder lying on
the surface of field or partly en-
bedded in it. Perhaps there will be NO
other large stone within a quarter of a
mile of it, nor a hill from which it could
says the Newark SUNDAY Call"
How did it come to have this solitary
setting in the landscape, reminding one
of the hermits of old, who fed to the
have rolled into the meadow beneathl
wilderness to abide alone? Is this its
native home and does it remain from free
choice, or was it hurled her and com
PEELED to stay through the ages without
being consulted?
A volume recently issued by the State
Biologists of New Jersey gives the an
swer to the question and tells much else
that every Jerseyman ought to know
about his State. The book is called ''The
Glacial Geology of New Jersey, 'and was
written by Rolin ID. Salisbury, assisted
by Henry B. Kuemmel. Charles e. Beet
and George N. Knapp.
In a world the bowlder was probably
borne to its present site from distant
point many ages ago. The northern part
of New Jersey is overspread with man
tie of clay, sand, gravel and powders,
which are called the drift. Sections of
the drift may be seen at hundreds of
places along the railroads and wagon
roads in northern parts of the State
and in numerous excavations for build
ing or other purposes. The surface is
often characterized by the presence Of
large stones or powders, sometimes of
huge size. The southern limit of the
drift in New Jersey is an irregular line
extending from Perth Amboy to a point
on the Delaware river little below
Belvidere.
That the soil, gravel, stones and rocks
forming the drift were usually borne to
given spot from distance is attested
by the fact that the material is usually
different from the native rock underlying
it. For example, where the underlying
rock is limestone, powders of sandstone,
conglomerate or gneiss, along with those
of limestone, may be found. They could
not have come from the disintegration
Of the limestone any more than grapes
could come of thistles. In like manner
the drift covering trap rock often con-
tains, in addition to bowlders of trap,
powders from a great variety of other
formations. 1t was long since recognized
that the materials of the drift did not
originate where they now lie. Hence the
name drift.
The thickness of the drift in this State
averages between twenty and forty feet.
And yet there are depths of NOR than
250 fet, and in Ohio and Western New
York tn depth is even 500 feet. The va
riations in the thickness of the drift are
often great within short distances. Some
times you will see the native rock show
ing above the surface. One hill may
have barely enough to cover the rock,
while the next may be composed of drift
from base to summit Sites for reser-
voirs are sought where the drift is thin
and the solid rock is close to the sur
face.
While the drift may be found on the
mountains of the State, on the whole it
is deeper in the valleys. The removal of
it would increase the present elvations.
and specially, it is said, about Newark
and Haekensack.
1t has been said that the drift is heter-
ogeneous, both in the quality and size
of its constituents. Some of the bowl
ders are twenty to thirty feet in diane
ter, and on the other hand much Of
the drift is only sand or clay. Sand
stone and shale prevail in and near New
ark.
Where did all the drift come from
1t was borne by natural forces to the
places where it was found, but from
what distances? Probably it was car
ried not more than a hundred miles. 1t
is believed that it came, most of it, from
the rick formations in the upper end Of
the State, or from their extensions in
lower New York. Only a small por-
tion came from more distant sources to
the north,s Mr.: Salisbury says in his
work that stones and powders have been
lifted much above the ledges from which
they came Bowlders Of Newark sand
stone are often found on the ridge of the
Palisades, hundreds of feet above their
source, and on the east side Of Jenny
,Irmp maintain IN {Varrar1 Csounfv fho,.o