The Corvallis gazette. [volume] (Corvallis, Or.) 1862-1899, 1890-11-14
A NATURAL BRIDGE OF AGATE.
Some of the Wonderful Things In Chalce-
dony Park, Arizona,

Some of the Wonderful Things In Chaloe-
dony Park, Arizona.
Among the Great American wonders
is the silicified forest known as Chalce-
dony Park. situated eight miles south
| of Corrizio. a station on the Atlantic
and Pacific railroad, in Apache Coun-
ty, Arizona. The country formation is
sandstone on volcanic ash. and the
trees are exposed in gulches and basins
where the water has worn the sand
stone away. or are buried beneath the
sandstone, their ends protuding from
between the formations. The locality
was noticed in 1858 by the Pacific rail-
roads exploring survey. The jasper
and agate generally replaced the cell
| walls and fibers. and the transparent
quartz filled the cells and interstices.
especially where the structure was
broken down by decay. These cell
| centers and cavities produced condi-
tions favorable not only for the deposi-
tion of silica as quartz, but also for
the formation of the drusy crystalline
cavities of quartz and amethyst that so
increase the beauty of the material.
There is every evidence to show that
| the trees grew beside some inland sea.
| After falling they became water-logged,
and during decomposition the cell
structure of the wood was entirely re-
placed by the silica from the sandstone
in the walls surrounding this great
inland sea. Maj. John w. Powell, who
has visited all these regions, says:
The wood consisted of logs water
rolled before burial. and are now
gradually weathering out of their ma
trix. The inclosing rock is sandstone
and cretaceous shale of the series
known as Jura-trias. and lying immedi-
ately above the Chinarump. Agatized
wood containing much semi-opai has
been formed in California (and possibly
in Arizona) under volcanic deposits, but
the wood in question is not associated
with volcanic material; its matrix is
sedimentary.''
The red and yellow coloring matter
is derived from the oxide of iron in the
sandstone, which is red, and the black
may be due to partial carbonization or
to oxide of manganese. The bark in
nearly every case has been decayed be-
fore silicitication. and even part of the
other layers of the tree is often gone,
but the difference between the oxidation
on the surface and inside is that the
surface to the depth of half an inch is
SO altered and changed that it has the
appearance of bark, and is generally
supposed to be such.
There is every indication that the
deposit is of considerable depth. Over
the entire area trees lie scattered in
! all conceivable positions and in frag-
ments of all sizes, the broken sections
\ III 1>,l4 0E
wheels. A tree $50 feet in length is
often found split into as many sections
of almost uniform length, presenting
the appearance of having been saWn
asunder for shingle-blocks by some
prehistoric forester or broken into
countless fragments. ranging from the
size of a small pebble to that of fair
sized bowlder, also fractured into per.
feet shaped cubes as if cut by apid-
ary. These multiplied fractures are
the result of alternate heat and cold.
produced by atmospheric changes act
iny on the water in the assures of the
tree.
A phenomenon perhaps unparalleled
and the most remarkable feature of the
park is natural bridge formed by a
tree of agatized wood spanning canon
45 feet in width. In addition to the
span fully fifty feet of the tree rest ON
one side making it visible for length
of over 100 feet. Both ends of the
tree are imbedded in the sandstone.
1t averages 3 - feet in diameter.
feet at the tlickest part, and 3 at the
smallest. Where the bark does not
adhere the characteristic colors oi
jasper and agate are seen. Although
the wood is beautiful to the naked eye
a microscope is needed to reveal its
greatest clarns; not only does the
glass enhance the bril!iancy of its
colors, but it renders visible the struc.
turc. which has been perfectly pre-
served even to tie f"rnIS of min f.. coils
and is more beautiful now than before
the transformation.
DR.. p. H. Dudley examined micro
scopically some sections of this woot
and found that part of it, at least, be
longs TO the genus Araucaria, ont
Norfolk Island pine of the South Paci
tic Ocean, according to the same author
itv, grows to a height of 100 to 2O'
feet. Other portions were found to re
semble our red cedar, Juniperus Vir
giniana, when grown in the extreme
South. The cell structure of some o
the wood indicates growth in a mild
uniform climate, the annual rings be
ing marked by only one. two, three, OF
more slightly smaller hexagonal o.
rounded. not tabular cells. as is usual
ly the case. The name of ''Chinarump'
has been suggested for this material b,
Maj. John w. Powell. this being th'
Indian name for the substance. Thes'
trees, according to 'one of the Indial
myths, were believed to be the bolts o
the arrows used By their god. 1t ha
been extensively used by them il
making spear and arrow points.