tiviues take place in three program areas, research and devel- 

 opment, education and training, and support and collabora- 

 tion, each with a Program Coordinator overseeing and 

 coordinating the work in their specific area. Staff, however, 

 can and often does participate in several projects at a time, 

 which can fall into more than one of these program areas; for 

 each project the corresponding coordinator oversees the work 

 done on it. 



The second event, which resulted in a major challenge to 

 CAL staff, was the year long construction project at MSC to 

 retrofit the ventilation system. In contrast to earlier planning, 

 this project resulted in a ma|or disruption, since halt of the 

 CAL facilities were closed down between January and August. 

 Thanks to the gratefully acknowledged help from the Na- 

 tional Museum of Natural History, temporary spaces could be 

 identified within MSC to keep most of the programs going. 

 However, the education program especially was seriously dis- 

 rupted, and some ma|or equipment, that could not be moved 

 to temporary quarters, was shut down for several months. 

 That the overall work progressed quite satisfactorily is testi- 

 mony to the outstanding efforts made by the CAL staff to 

 overcome these difficulties. 



In the research program on mechanical properties of materi- 

 als, a major milestone has been passed. The quantitative rela- 

 tionships between mechanical properties and environmental 

 conditions (temperature and relative humidity) have been 

 worked out for a large number of material types and this, in 

 turn has enabled the researchers to formulate safe ranges for 

 these environmental conditions inside which fluctuations pose 

 no danger to the objects in storage or on display. The possible 

 variations from the general set points of 50% RH and 68 de- 

 gree F. are indeed much larger than has generally been as- 

 sumed in the conservation literature; as a result substantial 

 savings in energy costs may be realized in operating the cli- 

 mate control systems in museums. A number of special sym- 

 posiums has already been organized at various locations to 

 disseminate these results to the museum community. Several 

 museums nationwide that were planning new construction 

 and/or climate control systems have asked for detailed infor- 

 mation to include these data in their planning. At the 

 Smithsonian, this work may lead to significant savings in the 

 control system acquisition and operation at the planned Dul- 

 les Airport facility of NASM. Moreover, in order to assess the 

 possibility of savings in other facilities, the main investigators 

 have been assigned on a special detail to a planning group at 

 ODC charged with the drafting of Institutional guidelines for 

 environmental control standards. 



The program of research into the pteservation of photo- 

 graphic materials successfully developed a packing technique 

 which provides sufficient humidity control allows inside the 

 package to allow the use of commercially available freezer 

 technology for the long term storage of photographic materi- 

 als. The advantage of freezer storage are in lower temperature, 

 hence longer life expectancy, and in greater energy efficiency. 

 Moreover, using commercial technology makes the equipment 



scalable to the size of the collection, from a household size 

 freezer, through supermarket freezers, to walk-in freezer 

 vaults. This will make cold storage a feasible and affordable 

 preservation strategy for small and large collections alike. At 

 CAL, a pilot demonstration project has been started. 



In the modern materials preservation research, attention 

 centered on the preservation of magnetic storage media, espe- 

 cially videotape. It appears that the determining factor in the 

 loss of use of the information is the chemical breakdown of 

 the adhesive binder holding the magnetic particles. Hence, 

 the research focussed on the development of a technique to as- 

 sess, non destructively, the degree to which this chemical dete- 

 rioration process is progressing, in order to make informed 

 decisions as to when to copy the information. Based on prelim- 

 inary results, the use of attenuated total reflection Fourier 

 transform infra red spectrometry appears to holds good prom- 

 ise, and this work will be continued. Research on the chemi- 

 cal ageing of paper under natural and accelerated conditions, 

 and the relationship between chemical and physical deteriora- 

 tion, progressed on schedule; since under not overly exagger- 

 ated conditions these processes are rather slow this is a multi 

 year project. 



The conservation of the neolithic plaster statues from Ain- 

 Ghazal, Jordan, entered its final phase, the reassembly and re- 

 construction. An agreement has been reached with the Sackler 

 Gallery and the Jordanian government, for a temporary ex- 

 hibit at the Sackler gallery of these unique objects after the 

 completion of their conservation, in late 1996. 



Work on the trace element characterization of archaeologi- 

 cal ceramics was seriously hampered by a prolonged shutdown 

 of the nuclear reactor at the National Institute for Standards 

 and Technology (NIST), where CAL operates a facility for neu- 

 tron activation analysis. This provided one more argument for 

 the need to develop alternative trace element analysis facili- 

 ties, and a request has been submitted tor the FY96 research 

 equipment pool for funding to acquire a inductively coupled 

 plasma optical emission spectroscopy instrument, later to be 

 augmented by ICP mass spectrometry. On the other hand, 

 good progress was made in the stable lead isotope ratio charac- 

 terization of archaeological metal sources. Collaborative work 

 on the early bronze age "Great Orme" tin mine in the UK was 

 brought to conclusion, and the proiect on Nigerian (Benin 

 and Ife and Igbo-Ukwu) bronzes produced a first series of 

 promising data. 



In the biogeochemistry program, work continued on the de- 

 velopment of molecular dissection techniques for light ele- 

 ment (carbon, nitrogen and oxygen) isotopes, and, in 

 collaboration with the Geophysical Laboratory of the Carnegie 

 Institution, on the comparison of isotopic compositions of pro- 

 teins from fossil, Cambrian and contemporary, Hawaiian 

 shells of the brachiopod Lingula. In collaboration with the an- 

 thropology department of NMNH, and with funding from 

 the James Smithson society, a vacuum line sample preparation 

 facility for light element mass spectrometry (and accelerator 

 mass specrrometry radiocarbon dating) was constructed at 



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