| REPLY BY INSTITUTO PORTUGUÊS DE
ARQUEOLOGIA TO CAR-ICOMOS ALQUEVA REPORT
João Zilhão (Director, IPA,
Instituto Português de Arqueologia) and
António Martinho Baptista (Director, CNART,
Centro Nacional de Arte Rupestre), September
21, 2001.
The following document is copied
verbatim from the following web
site:
1. IPA/CNART express their
satisfaction for the courteous, considered
and balanced nature of Dr. Bertilsson’s
report. Before commenting on the details,
we want to emphasize that, throughout the
process leading to its production, Dr. Bertilsson
followed at all times what we believe to
be proper scientific procedure, seeking
information before forming an opinion and
displaying sincere and due appreciation
for the work carried out under difficult
and time-stressed conditions by the CNART-led
Alqueva recording team. This stands in marked
contrast with previous CAR-ICOMOS work in
Portugal, specifically the December 1994
mission to the Côa valley. This mission
eventually led to a January 1995 report,
signed by Jean Clottes, where it was suggested
that the best way to preserve the Côa valley
petroglyphs was submersion by the reservoir
of the Foz Côa dam, then under construction.
That mission clearly exceeded its mandate,
and its suggestions were submitted with
no consideration whatsoever for the opinion
of Portuguese colleagues, ending up in what
were clearly nonsensical recommendations,
as subsequent events demonstrated. Dr. Bertilsson’s
procedure and report represent a clear break
with such past experience, and constitute
a sound basis upon which CAR-ICOMOS can
establish itself as an expert body respected
in the world of archaeology as a whole.
We can only hope that his example will be
followed by others in the future.
2. We gladly recognize, therefore,
that this is the kind of expert assessment
work the world of rock art badly needs in
order to establish itself as a fully professional
field of scientific research. Nonetheless,
IPA/CNART express their regret that Dr.
Bertilsson did not provide an unambiguous
statement on the nature of the declarations
reproduced in the front page of the September
8 issue of the Portuguese weekly newspaper
EXPRESSO. These declarations were
attributed to Dr. Zuechner, misidentified
as “secretary-general of CAR-ICOMOS”. Even
if Dr. Zuechner’s authority to produce such
declarations, supposedly on behalf of UNESCO,
is implicitly disavowed by Dr. Bertilsson’s
report, it would have been better, if nothing
else for the sake of clarity, to acknowledge
it explicitly.
3. Dr. Bertilsson’s references
to the use of the bichromatic method by
CNART are probably due to a misunderstanding
of the situation, easily explained due to
the short duration of his stay. Contrary
to what the uninformed reader might be led
to believe, CNART has never used the bichromatic
method as a standard routine procedure.
Throughout the several years of recording
work in the Côa valley, for instance, this
method was never used, not even once. In
the Alqueva, CNART used it in a very small
number of Guadiana panels for two reasons.
First, because CNART used the Alqueva project
as a field school, an opportunity to train
a new generation of Portuguese archaeologists
in the techniques of rock art recording,
including those that were widely used in
the past but are currently abandoned or
out of favor. Second, because this was a
rescue operation, where time is the paramount
conditioning factor, and, therefore, rapidity
and cost-effectiveness take precedence over
other considerations. We are sure that Dr.
Bertilsson understands these reasons very
well, since he does not object to our use
of other recording techniques that imply
potentially damaging, even if minimally
so, contact with the decorated surfaces,
such as latex molding. Even if they are
widely used in rock art studies, we have
chosen to avoid the application of such
techniques under normal research conditions,
as is the case in the Côa valley. We used
them in the Guadiana because submersion
of this rock art means that it will be unavailable
for study for several decades. Under such
circumstances, we believe that production
of replicas of the decorated surfaces that
are as exact as current technology permits
must be at the top of research priorities.
4. We wish in any case to stress
that we fully agree with Dr. Bertilsson
and CAR-ICOMOS in that the bichromatic method,
and indeed any other application of paint
over engraved rock surfaces, should be avoided.
In fact, over the last decade, as was widely
acknowledged in the wake of publication
and discussion of the Côa valley work, Portuguese
rock art researchers have pioneered the
development of alternative, non-intrusive,
and more performing techniques for the recording
of petroglyphs. We have also designed methods
of presenting rock engravings to the public
that effectively dispense with the use of
paint to enhance the visibility of the motifs.
Such a use is still widespread in many countries,
particularly in Scandinavia, where petroglyphs
are routinely filled with white or red paint
in order to facilitate observation by the
untrained eye of the visitor, in spite of
the growing international consensus that
the practice should be abandoned. IPA/CNART
therefore cannot but welcome the position
of CAR-ICOMOS in these matters so clearly
stated by Dr. Bertilsson, and look forward
to the recommendations to that effect that
CAR-ICOMOS will no doubt present to the
governments concerned. In the framework
of different international collaborative
projects, including the Swedish-led RockCare
project directed by Dr. Bertilsson himself,
IPA/CNART have made their know-how available
to all those that requested it, and remain
willing to assist CAR-ICOMOS in obtaining
worldwide adherence to the standards in
recording and presentation of petroglyphs
to the public that have been pioneered by
Portuguese researchers.
5. Dr. Bertilsson suggests that
“modern high-tech methods”, such as laser
scanning, be used to complement the Guadiana
recording work. Over the last three years,
IPA/CNART, in collaboration with INETI,
have carried out an experimental project
to apply high-resolution laser scanning
and stereophotogrammetry to the recording
of the Côa valley rock art. With regard
to laser scanning, this project uses technology
and know-how initially developed at INETI
(Instituto Nacional de Engenharia e Tecnologia
Industrial) for military and industrial
purposes. The results obtained show that
even when the best quality, most expensive
sensors currently available are used, the
resolution of available technology is still
insufficient. Fine-line engravings, such
as those that make up the vast majority
of the Côa valley Paleolithic art, remain
invisible even to the best possible hardware/software
combinations. The method works quite well
for the larger pecked and abraded motifs
but still requires intensive intervention
of highly trained people in the final image-processing
stage of the recording process. Our conclusion
is that these techniques are extremely valuable
for the purpose of obtaining accurate, three-dimensional
digital descriptions of both the rock-art
motifs and the rock surfaces/volumes on
which such motifs are inscribed in situations
where traditional molding techniques should
be avoided because of preservation issues,
or cannot be used because of the sizes or
the shapes of the volumes involved. This
is the case, for instance, when production
of 1:1 replicas of large panels is needed
for museographic purposes, and indeed it
was for such purposes that the IPA/CNART/INETI
project was initially designed. The systematic
use of such techniques in the Alqueva would
be too expensive, too slow, and too cumbersome.
Moreover, the results obtained would in
any case be qualitatively inferior to those
obtained with traditional recording techniques.
Quite simply, our experience indicates that
the best hardware currently available for
the Alqueva work is the extremely powerful
combination of a well-trained human hand
with an experienced human eye. That said,
the use of stereophotogrammetry, for instance,
may be of great help in securing the digital
records necessary for the future production
of replicas for a museum audience, should
indeed be used for that purpose where a
selection of the best-quality Alqueva panels
is concerned, and IPA/CNART will forward
such a recommendation to EDIA.
6. IPA/CNART completely agree with
Dr. Bertilsson that the rock art panels
found at Alqueva should not be cut loose
and relocated. This is simply not an issue.
In fact, statements to that effect were
already clearly made in the preliminary
report presented by CNART last May (http://www.ipa.min-cultura.pt/news/noticias/DecGuad/relatCNART),
in the wake of CNART’s first assessment
of the situation, following initial reporting
of the newly found rock art sites located
in the Portuguese margin of the Guadiana.
7. Empirical observation of the
Tagus Valley rock art, which for the most
part has been submerged for the last 30
years, ever since the reservoir of the Fratel
dam was filled up in the early 1970s, indicates
that the Guadiana rock art, made of similar
motifs, with similar techniques, on similar
kinds of rocks (greywacke, etc.), and in
a similar river margin setting, will not
be significantly affected by a long period
of submersion. Where this issue is concerned,
therefore, IPA/CNART is of the opinion that
the burden of proof lies squarely on the
side of anyone believing otherwise.
8. As publicly stated by EDIA and
the Minister of Planning in a press conference
of May 14, 2001, the ensemble of finds made
in the framework of the Alqueva archaeological
salvage project, including the rock art,
will be presented to the public through
a Museum facility to be built in the region.
9. IPA/CNART are devoted to the
study, protection and promotion of archaeological
heritage at least as much as all other bona
fide colleagues and institutions in the
profession, in Portugal and elsewhere. As
such, we would naturally prefer a situation
where the Guadiana rock art continued to
be enjoyed in its current setting for many
generations to come. However, IPA/CNART
acknowledge that they live in a world where
conflicts between such preferences and the
needs of society as a whole are inevitable.
When such conflicts arise, the costs and
benefits of all possible solutions must
be weighed and decisions must be taken after
careful consideration of the different issues.
The potential benefits of the Alqueva dam
were discussed for decades, and the Portuguese
government eventually made the decision
to build it. The role of archaeologists
in such a situation is that of carrying
out the mitigation measures deemed appropriate
and in a framework of costs determined by
the overall budget of the project developer.
Situations such as those which occurred
six years ago in the Côa valley are entirely
exceptional and IPA/CNART in no way want
to be part of actions which might be interpreted
as suggesting that they should instead be
the norm.
10. Where the Guadiana rock art
is concerned, IPA/CNART understand and welcome
the concern of colleagues worldwide. We
are well aware that many countries have
no rock art at all, or only have rock art
of minor quality or not very well preserved.
We understand the natural instinct of colleagues
from such countries to oppose even the concept
that rock art may be submerged or otherwise
affected by development. But modern societies
constantly face the need to make choices
on which parts of their archaeological heritage
must be preserved unchanged, and which should
be transformed into historical documentation
or removed to museum facilities, and this
applies to all kinds of archaeological heritage,
including rock art. Ranking the importance
and significance of archaeological resources,
including rock art, is therefore necessary,
even if it is one of the most difficult
tasks faced by institutions devoted to their
management. But this is inevitable, particularly
in countries that are archaeologically rich.
Such is the case with Portugal and Portuguese
rock art, and that is both our fortune and
our problem. But IPA/CNART do not shy away
from the responsibility of dealing with
it and, in this context, wish to make it
clear that the Guadiana rock art, undoubtedly
of value and significance, must be placed,
in Portuguese terms, in a third-from-the
top category. In our opinion, the top level
is occupied by the Côa valley rock art,
which is in a category of its own. The second
level is occupied by the Neolithic and Copper
Age rock art of the Tagus valley, the rich
ensemble of rock-shelters with well preserved
naturalistic, subnaturalistic and abstract
Neolithic and Copper age paintings that
dot the countryside of many interior regions
of Portugal, and by the recently found ensemble
of Paleolithic engravings of the upper Sabor.
The Guadiana ensemble, together with the
rock art of the Northwest, among others,
is in a third level, still of national significance
but clearly not representing a heritage
value of such importance as to be deemed
an absolute obstacle to the construction
of a dam which Portuguese society, after
decades of debate and controversy, considered
as a strategic economic facility, and, accordingly,
legitimately decided to build.
11. IPA/CNART warmly welcome the
generous offer of assistance made by CAR-ICOMOS,
and will no doubt take advantage of it,
should the need arise. IPA/CNART reassert
that all the recording work will be completed
before the end of the year, well in advance
of the inundation of the Guadiana rock art. |
World
Archaeological Bulletin