Year: 1875

1t is not always that geological irves-
LEGATIONS have as their object phenom-
ena which are of general interest, and
with which all are more or less familiar.
This is certainly the case, however,
with the study of the "giant kettles /"
in the neighborhood of Christiana, Nor
way, which has been lately carried on
by Professor Kjerulf and some of his
students. There is hardly any running
stream in our country of any consider
able size which does not give proof of
the power of water and stones in motion
in what are popularly called "pot-
holes" An eddy in the stream where
the current is strong sets few pebbles
in revolution. These commence de-
preston, into which larger stones fall,
and the grinding is continued until a
cavity has been produced perhaps sew
eral feet in depth, and almost perfectly
round. These are often to be observed
not only in stream beds, but also in
rocks on the sea-shore, where the rush
of the tide must supply the motive
force.


The famous "giant kettles" of Nor
way are simple "pot-hOles on larger
scale, snd produced in former times
under somewhat different conditions
than we have at present. The super
stition of the people represents them
as having been made by giants. In
some places, where the form is oblong
and irregular, fancy has seen in them
the footprints of these emOnsters, while in
one place, where the road goes directly
through a very large kettle, the saying
is that there st. Olaf turned his horse
around. On the west coast of Norway
another name is used, aud they are
spoken of as giants chairs.


The description of one of these ket-
ties examined by Professor Kjerulf will
give some idea as to their size and gen.
eral character. At the surface it had q
diameter of about eight feet, being
slightly elliptical in form. It widened
considerably in the descent, and then
contracted again at the bottom. It is
interesting to note that the walls were
distinctly worked out in a spiral, which
could be traced from top to bottom. In
the case of some other kettles examined
the spiral was so perfect that the cavity
could be compared to the impression of
a gigantic snail.


The total depth of the kettle in ques-
ton from the highest point of the mar
gin was forty-four feet, the axis inclin-
ing somewhat toward the west. It was
filed, as is always the case, with gravel
and broken rock, though toward the
bottom numerous, so-called grinding
stones were found, some of them 300
pounds in weight, and all smooth and
ellipticai in shape. 1t was through
their revolution that the excavation had
been made. 1t required thr men
working for fifty days to clear this giant
kettle of its contents, and the whole
amount taken out was estimated at 2, $50
cubic feet, some of the stones bSiug so
large that they had to be mined before
they could be boisted out.


The kettles in general present much
the same features as the one which has
been described, though there is great
variation in ratio of width to depth,
many of them oeing shallow, larger AZ
the top than at the bottom, and very
properly are called kettles, while others,
as the one alluded to, are deep, aud
could better be called wells. 1t is TO
be observed that they are found by no
means necessarily in present river chan
nels. They are most common in the
neighborhood of tho great flords.
though they have been observed at a
height of 1 200 feet above the sea. In
regard to their origin, the best authori-
lies refer it to the time when the land
was covered by enormous glaciers, such
as exist at the present time in the upper