Another unusual natural phenomenon of the Black Hills country is the
Devils Tower across the South Dakota state line in Wyoming. This is a
great column of igneous rock towering 1,280 feet above the Belle Fourche
river, whose course is near the base. Devils Tower has the distinction
of being the first national monument created under the Antiquities Act
of 1906. It was established by proclamation of September 24 of that
year, by President Theodore Roosevelt.
[Illustration: _Devils Tower in Wyoming’s western border of the
Black Hills National Forest._]
THE ANTIQUITY OF MOUNT RUSHMORE
_By the late_ JOSEPH P. CONNOLLY
_President, South Dakota School of Mines_
At the Battle of the Pyramids, Napoleon is reported to have exhorted his
men by saying, “Soldiers, from these pyramids forty centuries look down
upon you.” From the standpoint of human history four thousand years
represent great antiquity indeed. But as one gazes upon the rugged
slopes of Mount Rushmore, he is face to face with antiquity beside which
the age of the Egyptian pyramids seems but a moment.
How old is the granite of Rushmore? We have a yardstick by which we can
measure that quite accurately. Not far from the mountain, in a
subsidiary mass of granite, there was found a few years ago a small
piece of coal-black, lustrous mineral known as pitchblende or uraninite,
of which the chief constituent is the heaviest known element, uranium.
We know that uranium continually undergoes atomic disintegration,
changing at a slow, but uniform and measurable rate into lighter
elements. The end product of this change is the metal lead. If we submit
the specimen of pitchblende to chemical analysis, determine how much
lead it contains, how much uranium is still left, it is a comparatively
simple calculation to determine from the known rate of change, the
number of years that have elapsed since the pitchblende came into
existence. That experiment has been performed and the result is one
billion four hundred and sixty-five million (1,465,000,000) years. Bear
in mind that this enormous figure represents the time that has elapsed
since the molten rock came to rest at some depth under the surface of
the earth, and cooled sufficiently to crystallize into granite. It
represents the age of the solid granite.
But, although the granite of which the mountain is composed dates back
to a period almost inconceivably remote, Mount Rushmore itself is much
younger. We know that all of the granite mountains of the southern Black
Hills were carved out of the rocks by the process of erosion. Field
evidence indicates that fairly early in the Tertiary period,
approximately thirty million years ago, erosion had carved out the
topography of the Black Hills into much the same stage as we see it
today. Perhaps Mount Rushmore was not fully born in that period; its
form may not yet have been completely sculptured under the chisel of
time, but we know that its age must be measured in millions of years and
not in centuries.
Mount Rushmore is a child of weathering and erosion. They brought the
mountain into being and gave it form. But those relentless parents will
not be content to leave their child as they fashioned it. They will
continue their work of disintegration on the surface of the rock and
along the cracks, until eventually they will completely destroy the
mountain they formed, and long before the mountain will have been
destroyed, the magnificent carvings of man will disappear. “How long,”
we anxiously ask, “will the carvings endure?” Two processes will tend
eventually to destroy the memorial, chemical weathering and physical
disintegration.
[Illustration: _A typical view from the Needles highway with the
Cathedral Spires in the background._]
[Illustration: _Fantastic formations in the Badlands. The variegated
coloring is at its best in the early morning or the late evening._]
Chemical weathering will take place very slowly, so slowly that if it
were the only destructive process we had to consider, we could with some
confidence say that the memorial would endure for hundreds of thousands
of years. And the progress of chemical weathering will probably be
impeded by the sculpturing of the memorial, for on the figures the rock
will be smoother, water will drain off more rapidly instead of
penetrating, lichens and other vegetation will not have as secure a
foothold as on the natural face of the rock, and thus will not
contribute to so great an extent their destructive acids to such waters
as do penetrate.
Physical disintegration is somewhat more to be feared. This operates in
two ways, by exfoliation due to changes in temperature, and by frost
action. Differential stresses set up by unequal expansion and
contraction, owing to the poor heat conductivity of granite, tend to
spall off or _exfoliate_ the surface layers of rock.
When water gets into the cracks and pores of the rocks and freezes, it
exerts an enormous pressure, a pressure that will spall off flakes and
blocks of rock. The artist and his associates, fully aware of this
hazard, have guarded against it. All cracks and fissures have been
carefully avoided in the sculpturing so far as is possible. Such as have
been impossible to avoid are being sealed to prevent the ingress of
water, thus inhibiting to a very large extent both frost action and
chemical weathering.
We have traced in part the geological history of the Mount Rushmore
region, hoping that by learning something of its past we may predict
something of its future. We see the hazards to which the memorial is
exposed. We must frankly recognize them and guard against them so far as
possible, as it would be folly to ignore them. If the science of geology
can do no more in a practical way for mankind than to point out dangers
and sound warnings, it does a worth while service. “How long will the
memorial last?” Geology cannot answer specifically. An eminent geologist
has already given as definite an answer as it is possible to give, and I
can do no better than to close by quoting from the address given by the
late Dr. C. C. O’Harra at the unveiling of the head of Washington.
“How long will Mount Rushmore last? Many millions of years. The number
nobody knows. How long will endure this monumental, sculptured figure of
the Father of our Country which today we unveil? One hundred years? Yes.
One thousand years? Yes. A hundred thousand years? In all likelihood,
yes. A half million years? Possibly so, nobody knows. The time at any
rate will be long, far longer than we can readily comprehend. And this
doubtless will abundantly suffice.”
THE HALL OF RECORDS AND GREAT STAIRWAY
_By_ LINCOLN BORGLUM
The Hall of Records and Stairway have been part of the Memorial plan
from the beginning and are provided for in the so-called “Rushmore Bill”
of 1938. A good start has been made in the carving of the Hall, which
already has been excavated to the extent of seventy feet. Great care has
to be exercised in the use of dynamite in carving this hall, as in
carving the faces on the mountain, not to injure the stone which is to
remain. Careless explosions of large amounts of powder might crumble the
walls.
The Hall is located about two thirds of the way up to the mountain: the
entrance to it is in a small gorge or canyon, cut by the ice aeons ago,
to the right of the carved faces as one looks at them from below. The
Hall is on the opposite side of the gorge from the heads and is not
under them. The following is quoted from Mr. Borglum’s plan.
“The façade to the Hall’s entrance is the mountain wall 140 feet high;
supporting pylons, cut into the mountain, flank the entrance. The
entrance door itself is 12 feet wide and 20 feet high; the walls are
plain, dressed granite and of a fine color. I want to finish the inner
entrance wall in mosaic of blue and gold lapis. The depth to the door
entrance from the outer façade is 20 feet. The door, swung on a six inch
offset of the wall, will be of bronze and glass. Small, carefully
modeled bronze figures of historic importance from Columbus and Raleigh
to the present day will ornament the doors or be modeled into the
supporting frame. The walls of the entrance will carry in gilded bronze
immediately within the entrance ancient Indian symbols; British, French,
Spanish and American seals.
“The floor of the Hall will be 100 by 80 by 32 feet to an arched
ceiling. At the height of fifteen feet an historic frieze, four feet
wide, will encircle the entire room. Recesses will be cut into these
walls to be filled with bronze and glass cabinets, which will hold the
records stamped on aluminum sheets, rolled separately and placed in
tubes. Busts of our leaders in all human activities will occupy the
recesses between the cabinets. The original thought of a hall of human
records I developed at Stone Mountain in Georgia and my drawings and
full plans are extant; that was never completed.
“The records of electricity, beginning with Franklin, which has given us
light, heat, music, the radio, the telegraph, the telephone and controls
in power the extent of which we can hardly imagine, must be here,
together with the records of literature, the records of travel,
immigration, religious development and also the record of perhaps the
largest contribution that we have made to humanity, which has been free
controlled peace, a government of the people, by and for the people.
Struggle as we will that great contribution is today the cause for the
real unrest of Europe. Despotism, tyranny of every form is fighting us
wherever it can, to take away from humanity the power freedom gives
it—the power that freedom has given America.
[Illustration: _Opening of a gorge reached by the Great Stairway is
the massive twenty-foot-high entrance to the Hall of Records._]
“The Hall will be reached by a monumental flight of steps varying from
15 to 20 feet in width, which will ascend the mountain in front, a
little to one side of the sculpture, rising from a great granite disk or
platform in the canyon below, which may be used as a rostrum from which
speakers may address the public occupying the amphitheater facing the
great group.
[Illustration: _This picture shows the workmen busy in the early
stages of the work of carving the Hall of Records from the
granite._]
“These steps of granite and cement will be provided with seats at
intervals of every fifty feet; they will have a five inch rise and an
eighteen inch tread. The ascension from the foot of the steps to the
floor of the great entrance is four hundred feet; the entrance way from
the steps’ landing to the great Hall is 190 feet; the floor of this
Hall, reached by three steps, is two feet above the floor of the
entrance way in the canyon; this to provide for proper drainage.”
Owing to repeated requests from important organizations of women, the
urging of some senators and congressmen and Mr. Borglum’s own
realization of the part women have played in the development of our
country, plans had been under way for some years to include women in the
great Shrine of Democracy. There was no room in the rock which contains
the heads of the four presidents and the only other place seemed to be
the west wall of the granite cliff, or in the hall of records. To quote
again from Mr. Borglum, from a letter written in January 1940: “If we
decide that the west side of the mountain is suitable, I am for it. We
must work out a design that is fitting and in no sense harmful in the
matter of lighting or location to subjects determined upon and I am
entirely in favor of carving the faces of two or three women. If that is
determined upon, these figures will be near what has been known in the
Rushmore Law as the Inscription and there will be a special paragraph
given to the work and services of women. The original inscription
referred to the framing of the Declaration of Independence; that was
Jefferson’s work and the second was the Constitution. That was
Washington’s greatest service. The third dealt with the purchase of the
Louisiana Territory and the fourth, fifth, and sixth, the progress
towards the south and southwest, involving Florida, Texas and
California, which included Arizona, a portion of Nevada, Utah and a
portion of Idaho. The seventh paragraph brought in the Oregon cession
from England and the purchase of Alaska. There was one paragraph for
Lincoln and one for the finishing of the Panama Canal, which was
achieved by Theodore Roosevelt.
[Illustration: _The corridor leading from the doorway into the Hall
of Records, showing the marks of the stonecutters’ tools._]
“So by these suggestions you will see that a splendid paragraph can be
developed for the part women have played in the development of the
nation.” In another part of the letter Mr. Borglum made a place for
women in the Hall of records and even suggested that a special hall
might be carved for them, as there is ample rock for many rooms.
Calvin Coolidge had been asked to collaborate on the inscription and
wrote the first two paragraphs. Mr. Borglum stood strongly for “Justice”
in the wording, whereas Mr. Coolidge insisted upon “Justice under the
Law.” Newspaper accounts exaggerated the discussion, which unfortunately
was terminated by Mr. Coolidge’s death.