ACKNOWLEDGEMENTS

This article was developed through a US/ICOMOS contract under a grant from the U.S. National Park Service and the National Center for Preservation Technology and Training. Its contents are solely the responsibility of the author and do not necessarily represent the official position or policies of the National Park Service or the National Center for Preservation Technology and Training.

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AUTHOR INFORMATION

A. ELENA CHAROLA obtained her degree in chemistry from the Universidad Nacional de La Plata in her native country, Argentina. She completed her postdoctoral work at New York University and stayed in the United States, becoming a citizen 20 years ago. She served as associate chemist in the Department of Objects Conservation at the Metropolitan Museum of Art, New York City, scientific adviser at ICCROM (International Centre for the Study of the Preservation and Restoration of Cultural Property) in Rome, Italy, and consultant to the Easter Island Program for World Monuments Fund (WMF). Since her return to the United States some 10 years ago, she has continued as technical consultant to WMF, including projects in other countries (Torre de Belem and Mosteiro dos Jer�nimos, Lisbon, Portugal, and Belvedere, Vienna, Austria) while being an independent consultant in conservation. She has been lecturer in advanced architectural conservation in the Graduate Program in Historic Preservation, University of Pennsylvania, and national chair of the Brick Masonry Committee of US/ICOMOS since 1996. Address: 3618 Hamilton St., Philadelphia, Pa. 19104

Received for review March 3, 2000. Revised manuscript received April 29, 2000. Accepted for publication May 15, 2000.