Carving A Cli££ <>f
Photo copyright by American Museum of Natural History.
Apatosaurs, or brontosaurs—a type abundantly represented
in Dinosaur National Monument deposits.
By Dr. Frank Thone
MUSEUM walls offer magnificent
opportunity and challenge to
curator, sculptor, mural
painter. You can back up
against them a pair of majestic Assyrian
winged bulls, brought from a long
buried city of the East. You can cover
them with Byzantine mosaics, rescued
from the ruins of an ancient basilica.
You can paint upon them vivid pan
oramas of life as it was when the earth
was young.
In the halls of the great museums
where the mighty bones of giants of the
past are displayed, it is not uncommon
to set against the walls’ wide spaces
huge slabs of rock with the dinosaur
fossils still sticking in them, the stone
chiseled away to leave the bones pro
jecting in high relief. A paddle-limbed
plesiosaurus, for example, just as he
sank to the bottom of the sea and died
and decayed, a hundred million years
ago, scarce a bone in his immense skele
ton budged out of place.
But scientists are out now to outdo
their own accomplishments. Not even
the halls of the greatest museums suf
fice to contain their ambitions.
The world’s first carven cliff of dino
saur bones is now shaking under the
drills and picks and hammers of work
men preparing the way for the scientific
chiselmen who will follow, to bring
about the resurrection of a whole mass
of saurian fossils and show them, in
place, as on a mighty wall, to be 6een
and wondered at by men.
The place is Dinosaur National Monu
ment, in northwestern Utah, one of the
smaller areas included in the U. S.
National Park system, but not adminis
tered as a National Park.
'T’HE concept of carving away the stone
*■ covering that hides a whole cliff of
dinosaur bones is a bold one. It was
originated by the curator of vertebrate
paleontology at the American Museum
of Natural History, Barnum Brown.
As with all bold concepts, the idea oi
a cliff-face museum of dinosaur bones
is fundamentally simple. It takes ad
vantage of two outstanding things: a
most unusual accumulation of saurian
fossil skeletons, many of them complete
and little disturbed; and a lucky chance
of geology that turned what was once
a floor into a wall.
When the dinosaur bones were de
posited in the particular stratum that is
the reason-for-being of Dinosaur Na
tional Monument, that stratum was the
bottom of some oozy coastal lagoon or
wide river estuary. The great car
casses drifted into one rather limited
area, nudged along by some trick of
wind or water current, sank to the bot
tom, and eventually became, buried
skeletons.
That was in Juras
sic time, which ended
about 125 million
years ago. The Juras
sic was the heart of
the 200-million-year
long Age of Reptiles
—the 13th century of
the earth’s zoological
Middle Ages.
Then ruled on
earth, and in the
heavens above, and
in the waters that
are under the earth
such an array of rep
tilian giants as were
never before seen
and never shall be seen again.
Greatest of these, at least in bulk,
were the sauropods; they included the
monster brontosaurs and diplodocus,
and the rarest and most gigantic of all,
the huge barosaur—bodies as big as
boxcars, necks like palm-tree trunks,
interminable tails. Barosaur measured
80 feet over all.
Into the quiet water of the ancient
lagoon they drifted, their skeletons pil
ing up side by side and overlapping
each other—a charnel-pit of giants,
under the water and the drifting silt
Photo by Hjtrnum Brown.
An aerial photograph showing excavation of the monument site.
Carnegie Museum Photo.
How the massive bones of a dinosaur are carved out. Square markings aid in charting the
exact position of the skeleton in the rock.
Ever thicker piled the silt; with unim
aginable slowness but with inevitable
sureness it hardened into stone, sealing
the fossilized bones tightly in place. All
this time the land was flat; the great
mountains of the West had not yet be
gun to lift their heads.
'T'HEN the slow heaving began. The
mountains grew to the youthful ripe
ness that is now theirs—for the Rocky
Mountain system is young, geologically
speaking. Strata were bent and tilted
until some of them stood on end. Among
DINOSAUR .
BONES
them were the strata in which the dino
saur bones were sandwiched; they final
ly came to stand at an angle of 80
degrees—just a little back-slope from
the vertical.
How much of the dinosaur layer was
exposed to the weathering of ages and
so lost, fossils and all, can never be
known. But the part that is left is a
veritable Bonanza of bones—waiting to
be mined.
For the “cliff” of fossils which Bar
num Brown’s enthusiasm and tenacity
is changing from dream into reality is
a buried cliff. You have to dig down
and clear away the other rock layers
from in front of it to get at it. The
sculptors take an existing cliff and carve
faces and figures upon it. The scientist
has to make his cliff first; but the pat
terns for the sculpture will be on it
when he gets it dug out.
Dinosaur bones w'ere first dug at this
site by Dr. Earl Douglass of the Car
negie Museum of Pittsburgh. The U. S.
National Museum and the University of
Utah have also removed many fossils.
These diggings worked across the ex
posed top of the fossil-bearing stratum,
and down either end; but there is still
a great buried slab in the middle. It is
to expose this that an artificial canyon
now is being dug in front, by various
groups of government emergency labor
under the direction of the U. S. National
Park Service.
After this deep, long pit has been
completed will come the turn of the
skilled chiselmen of the American Mu
seum of Natural History.
With air-driven tools they will carve
away the embedding matrix of stone
from around the bones, leaving them
firmly fastened to the background with
the cement of ages, but standing out
clear and bold in high relief.
It will not do, of course, to leave these
carefully carved-out fossils exposed to
the weather, particularly the powerful
weather of the West, stormy in winter,
hot in summer. The precious carvings
would begin to erode away immediately.
CO Mr. Brown’s plans call for a
vaulted roof to cover the whole
thing—the artificial canyon 40 feet
wide, with its north wall, bearing the
fossil carvings, 30 feet high and 190
feet long. The building will be mostly
roof, because the entire “hall” is un
derground.
Mr. Brown visions it: “Spotlights will
be directed on each of the skeletons. In
the center of the room are to be placed
lifelike models, made to scale, of each
of the animals whose skeletons are seen
in the rock, and on the south vertical
wall of the building will be placed a
gigantic mural 190 feet long and 20 feet
high, showing the topography of the
country, the flora, and the animals in
their natural habitat as they existed 140
million years ago.”