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Your Theories
Below are some of the theories sent in to this Web site about
ways to move and erect the moai.
Theory:
I am a fifth-grade student and have been researching Easter
Island for my school project. I have read your plans to
experiment with the best ways to move the moai. Your daily
dispatches are interesting and keep me in touch with your
latest activities. I'll be checking your site each day and
waiting to see what method for transporting the moai seems
to be the best.
I think that they used seaweed as a lubricant to help the
moai slide. I do not think they would use anything edible
because they were growing short of food.
Elizabeth Nyberg
Old Lyme, CT
Response from Jo Anne Van Tilburg:
Dear Elizabeth,
I agree completely with you! Food was much too important on
Rapa Nui to use in such a way! We think one option would be
the stumps of banana trees as lubrication - a renewable
resource because banana trees must be cut to grow fresh each
season.
Theory:
The rolling terrain could work as bridge piers, with logs as
rails to slide the statues from the quarry to the placement.
Or, the rocks were carved in place, only the rocks
transported to the final site. Or, the rocks were in place
to start with—they could have been excavated? Does the
island have enough wood for any of the methods?
Charles Wolff
Great Falls, Montana
Response:
The stone source for the moai came from the quarries and was
not present at the ahu sites. Today there is no available
palm wood, specifically Jubea chilensis, which was used by
the ancient Easter Islanders on the island. We will be using
eucalyptus wood, which was introduced later to the island,
but should be strong enough for our experiments.
Theory:
Team: Attach blocks to ends of statues, i.e. head and feet.
These blocks would have rounded outsides, where they touch
the ground, thus turning the statues into cylinders of a
sort, and roll them along roads or wooden rails to the site.
Near the site build a ramp of sand and roll statue up it,
then dig out in order to place, like Egyptians did with
obelisks.
(name withheld by request)
Response from Ted Ralston:
The technical capabilities of the ancient Polynesians were
quite incredible and certainly encompassed the use of
rollers, which are cylinders. However, no one has yet
evaluated the encasing concept from the point of view of
materials or technique. There is no evidence of any type of
encasing material in the record of the land, however.
Theory:
Would it not be possible to strap ropes from top to bottom
to prevent cracking of the statue, then use ropes wrapped
around trees and logs as pulleys further using logs as
rollers. Then at the site using pulley methods to erect the
statue. Finally cutting all the ropes and the statue is
erected.
George Durden
Houston, TX
Theory:
I would like to know if it is possible the moai statues
could have been loaded on to some sort of boat and then
sailed or rowed to the other side of the island? Would there
be resources on the island for them to build a boat & are
the waters calm enough to carry a statue that big safely
around the island?
(name withheld by request)
Response from Jo Anne Van Tilburg:
The waters are often very rough. Coastal loading areas in
the vicinity of the statue quarry are not known. However,
"canoe ramps" exist in some areas, that may have been used
for loading rafts. No clear evidence is available, but the
concept is feasible.
Theory:
One method which has not been fully explored is the
possibility that the moai were transported to their
respective ahu (platforms) via rafts. Since Rano Raraku (the
quarry), is relatively near the water, and since the vast
majority of ahu are situated on the coastline - it would not
be unreasonable to posit the use of rafts to transport the
moai around the perimeter of the island.
This seems to me at least as feasible as the prevailing
theories of dragging the statues over remarkably rocky and
hilly terrain.
David Brookman
Philadelphia, PA
Response from Jo Anne Van Tilburg:
The use of rafts as you describe is not an unreasonable
hypothesis; although there is no archaeological evidence of
a coastal loading site, canoe ramps exist and could have
been used to load statues on ramps. However, overland
transport is clear and unquestionable for 97 statues. Thanks
for the interest.
Theory:
The various theories of moving the statues by pivoting,
tilting, rocking, etcetera seem to consider the terrain as
it exists today. It seems that the first requirement to move
an object from point A to point B is that there must exist a
relatively smooth or navigable route between the two points.
This may have been a natural or artificial path of earth
and/or sand or other material since eroded away. Once you
have established the relatively smooth path the task of
movement without damage is much easier. Then methods of
mechanical advantage such as levers, inclined planes,
pulleys, etc. of various arrangements could do the job. It
is interesting to think of the possibilities if they had ice
available, or the means of making ice. At any rate I'm
suggesting hat the neoliths had to be transported over a
relatively smooth path.
Robert Homan
Las Vegas, NV
Response from Jo Anne Van Tilburg:
In fact, the known transport roads are relatively
accommodating but only very perfunctory and often smooth.
The terrain is quite hilly. No ice is available, then or
now. Thanks for the interest.
Theory:
One theory that probably has not been considered is the use
of water on land to move the megaliths. I don't mean
floating them on a barge down a river, but actually
constructing a large portable trough or tank that is filled
with water. The megalith is tied to a raft-like structure
and the tank is built around the megalith. The tank is
filled with water and the megalith is slid or floated
forward in the tank. The tank is then deconstructed and
shifted forward to allow for the next shift of the megalith.
Have you seen how a canal or a ditch is reinforced on the
sides when under construction? As the digging progresses,
the sides are shifted forward and relocated. Water is
obviously a plentiful resource for the island, and the fact
that many of these giant stones were moved makes it seem
slightly plausible that water could be used on land as part
of the plan.
Corrine Terebas
Buffalo, New York
Response from Ted Ralston:
No theory can ever be discounted - some have more support
than others do. The present evidence does indicate that a
relatively fixed amount of material (rocks) was used in the
"work train" that accompanied a moai in motion. Whatever
ramps, platforms, or fillers were required were constructed
with this loose material, then deconstructed as that step
was accomplished - very similar to the modern use of
scaffolding, wall forms, blocking, etc. However, the concept
of water tanks has not been considered.
Theory:
As a lay person, I'd say they used log-rollers to transport
the statue. To erect the statue I'd guess that they used a
wooden backdrop and log-rollers and used ropes to pull it up
the wooden backdrop with the help of the same log-rollers.
Sorta like the Egyptians used to erect obelisks.
Charles Ertel
Schenectady NY
Response from Jo Anne Van Tilburg:
Log rollers are reasonable to assume and we have tested
palmwood rollers. They function perfectly when fresh.
Theory:
Wouldn't be possible with their mortar technology to mix and
form these stones in place, and shape these forms in the
exact spots they now rest?
(name withheld by request)
Response from Jo Anne Van Tilburg:
The carving process, from beginning to final stages, is
clearly evident in the quarry, where all but about 30
statues were carved. These 30 came from other, smaller
quarries and were transported, finished, to their final
sites. Thanks for your interest.
Theory:
Dear Liesl Clark: It is always fascinating to see what sorts
of information gets out there! The statue we moved upright
here on campus was just short of nine tons and four meters
high and represented a slender style of statue. We
experimented with about four different methods of moving it,
one of which was the tilting method, same as Pavel Pavel,
but he used a group of men in closer to the statue with a
wooden bar. Ours were much farther away.
The reason this is not the method they used is because the
number of folks it takes to tilt it carefully are not very
many, but they make a heck of a scuffle with their feet, and
thus any amount of work would have produced three roads -
the prepared one for the moai transport itself, and two
other tracks or trails parallel to it made from the constant
scuffling of feet. Using that method we only moved it a few
feet before a soft section of our "road" caused it to dig
its own hole! We dumped it over a total of four times during
our experiments, three times forward, and one backward, and
that's the one that keeps getting repeated over the TV, with
the implication that method was a failure. It was not. That
was the successful method, and the statue, unlike Ms. Van
Tilburg's comment, is amazingly stable and no where near as
dangerous as it appears. It is tied down to the "pods" as I
called them. It fell over backward because our rollers
jammed forward of the center of gravity. Subsequent rolling
did not
If you would like me to compress a couple of photos and send
them your way, I would be happy to do that. They range in
size from about 70k to 110k. We are incidentally
experimenting with another statue at the moment, so this is
a nice coincidence! Please feel free to say hi to Jo Anne,
Claudio, Edmundo, Vince and others if you are in contact
with them. I wish them all the best of luck in their
experiments. Incidentally, I first worked on this in 1982,
and then with the big statue in 1987 after earlier failed
attempts in 1984. Pavel Pavel did his statue moving in 1986,
but had thought about it, he told me, in 1982. Regards,
Charles M. Love
Rock Springs, WY
Response from Jo Anne Van Tilburg and Ted Ralston:
Charlie, you may be interested to learn that rollers are of
little use...rolling, sliding, or both occur depending on
many factors, including interface friction condition, the
ground slope, and surface smoothness condition, material
variables. In our experiments, large-diameter palm rollers
on smooth surfaces, rollers predominate. On rough surfaces,
small-diameter rollers, lubricated sliding predominated. In
any case, the lower effort condition, be it rolling,
sliding, or a combination, will occur first. In all of our
experiments, roller management is extremely difficult.
Sliding works like a charm!
Theory:
Is it reasonable to presume that the statues were built on
their site rather than having to have been moved to it?
Elsewhere on this Web site it is stated that they are
constructed of volcanic ash. Perhaps this ash was mined and
transported to the site as a powder. It may have been used
to construct the statues using methods such as building a
sand castle or a snowman. The ash, of course, would have
been much more transportable than the fully assembled
statue. It is also interesting to note the masonry skills of
the Polynesian ancestors which is described also on these
pages.
(name withheld by request)
Response:
The tuff, or hardened volcanic ash (rock) that the moai are
made of came only from quarries around the island; the rock
was not present at the ahu sites.
Theory:
I seem to remember a theory I once heard about how the moai
were actually a type of concrete, and that there was a
residual chemical mixture on the stone. Is it possible that
the statues were poured into molds and then finished?
Perhaps some method of dissolving the stone after it was
quarried? Has there been any crystalline structure analysis
of the stones to see if this has any merit?
Ryan Remencus
St. Marys, Georgia
Response from Jo Anne Van Tilburg:
Ryan, the moai are carved of compressed volcanic ash from
quarries on the island at a place called
Rano Raraku.
J. Van Tilburg.
Theory:
Perhaps the stones were rounded at the quarry, rolled to
their final destination, then chiseled down to the end
products.
Randy Young
Denver, CO
Response from Jo Anne Van Tilburg:
Hello Randy, Good question. The quarry, which has been fully
mapped, contains 397 statues. All were finished before being
transported to their ceremonial sites.
Theory:
Could the statues have been created "on site" out of chunks
of lava left from ancient eruptions of volcanoes rather than
moved after carving?
(name withheld by request)
Response from Jo Anne Van Tilburg:
The archaeological record is very clear: the statues were
all finished prior to moving them to their ahu sites. The
pukao were shaped on site and the surface of the statues
smoothed before being lifted into place.
Theory:
I'm not particularly knowledgeable about the Easter Island
statues, but could the stones that were made into the
statues be moved to their destination and then chiseled or
the like into each statue. Or the bottom could be chiseled
into an arch shape for easier dragging by rope, maybe a
lubricant could be spread along the bottom by setting some
around it and moving the rock around the immediate area. Not
that many people would be necessary, I believe. As for the
erection of each statue a collection of smaller but fairly
large stones or logs or log-like pieces of wood could be
used for leverage and the statue could be lifted because of
the heavier base.
Kenny Linsky
Brooklyn, NY
Response from Jo Anne Van Tilburg:
The archaeological evidence is clear, that the statues were
all finished prior to moving them out of the quarry. We
agree that levers are essential for moving and lifting.
Theory:
I found the response from Jo Anne Van Tilburg, "The
archaeological record is very clear: the statues were all
finished prior to moving them to their ahu sites," very
interesting. Was it not harder to move them carved? Could we
please have more information on the record that the statues
were all finished prior to moving them. Do you know why they
had to be carved first?
(name withheld by request)
Response from Jo Anne Van Tilburg:
Karen, thanks for your message. There are 397 statues still
in the quarry, in various stages of carving. All of the
statues "in transport" to the ceremonial sites where they
were erected, in contrast, are fully carved, down to the
very smallest detail. It may have been easier to move them
uncarved, but our experiment showed very nicely that
fully-carved statues can be moved with no damage to them at
all. Our moai got safely to his ahu without breaking, thanks
in part to the design of the transport frame on which he was
lying. I don't know why they were carved before moving, but
I imagine there were many reasons. On Rapa Nui, there are no
simple answers to all questions, but we try to look within
the island's culture for clues. Thanks.
Past Attempts
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