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State of preservation of give information of a positive and precise during which collagen has changed to nature on the causes of the variations gelatin may prove to be of great value. the Dead found on Dead Sea samples (some T.B. KAHLE SIR-The article "Dead Sea Scroll parch­ on the same fragments) which undermine Capricornus School of Binding ments: unfolding of the collagen mole­ their study. As the authors note, we know and Restoration, cules and racemization of aspartic acid" 1 is damage has occurred, but its cause, and Berkeley, of interest since any method which will when it occurred are unknown. California 94701, USA improve on our knowledge of frag­ Plenderleith' found during the unrolling NICCOLO CALDARARO ments is important. The study on the con­ of Dead Sea Scroll fragments of cave 1 Fine Arts Museums of San Francisco, dition and deterioration of vellum which is that certain fragments were permeated and Tiburon Archaeological known to be approximately 2,000 years with a black bituminous substance which Group, old is interesting in itself, although the he identified as a decomposition product 1600 Holloway Avenue, identification into , calf or as to of the . During the unrolling he found San Francisco State University, origin of the material examined' ' would it necessary to dampen the Scrolls which San Francisco, California 94132, USA improve the information resulting from caused this substance to become sticky. t. Weiner, S., Kustanovich. Z .. Gii-Av, E. & Traub, W. their tests. This could be accomplished by This black substance apparently was gela­ Nature 287, 821}-823 (1980). a comparison made from samples of the tin. This incident brings up a very impor­ 2. Ryder. M.L. Nature 182,781- 783 (1958). 3. Poole , J .B. & Reed. R. Techno/. Cult. 3,1-26 (1962) scrolls known to be of goat skin and that of tant topic, that of the interventions made 4. Burton, D ., Poole. J.B. & Reed. R. Nature 184.353-534 modern goat skin prepared as we believe necessary by the fragile and rolled nature (1958). 5. Allegro, J.M. The Shapira Affair (Doubleday. Garden the scrolls to have been prepared'. In this of the scrolls. Careful identification of the City. 1965) . way Weiner eta/. could make a column to location from which each sample was 6. Reed, R. Ancient , Parchments and Leathers (Seminar Press, London, 1972). their Table 1 identifying the skin of each taken should have been presented by 7. Plenderleith , H.J . Discoveries in the Judean Desert /, scroll as well as the patches and other Weiner et al. This information could have Cave Vol ! (eds Barthelemy, D. & Millk . J.T.j) additions. As the authors state in their been correlated with published data on 39-40 (1955). 8. Cross, F.M. Jr Biblical Archaeo/. 17 (1954). papd "Using different skins in one the condition of the fragments as they 9. Araldite as an aid to (Ciba Tech. Note No. scroll and/or various parchment prepara­ were found and treated. Both 218, 1961). 10. Stambolov, T . Manufacture, Deterioration and tion treatments could conceivably influ­ Plenderleith' and Cross' report extensive Preservation of Leather. A Literature survey of theoretical ence the C:G index and the oiL aspartic treatments with moisture and oils to re­ aspects and ancient techniques (Central Research 9 Laboratory !COM. Amsterdam, 1969). ratios". move clay and/or relax the skins • The II. Kahle. P.E. The Cairo Geniza 2nd ed (Blackwell. Oxford, If, however, any relationship is to be materials used in the treatments and the 1959). originally adherent substance could have 12. Yadin, Y. (ed.). The TempleScroi/Vols. 1-3. (University drawn to the age of the samples and the of . 1984) . agents of deterioration, then the tests they altered analytic results. 13. Vermes, G. Times Lit. Suppl. 3 May, 50,501 (1985). carried out gave insufficient evidence, as This consideration of the condition of 14. Protsch, R.R. Catalogue of Fossil Hominids of (Fischer. New York, 1978). we have seen even within the scrolls there each fragment and their individual histor­ 15. Hedges. R.E.M. & Wallace. C.J.A. J. Archaeo/. Sci. 5, is variation. There must be a more com­ ies, including methods of skin preparation 377- 388( 1978). 111 16. La Joie. K.R .• Peterson, E. & Gerow . B .A. in prehensive sampling to form a basis for of which Stambolov has prepared a thor­ Biochemistry of Amino A cids (cd. Hare . P.E.) 477-489 comparison, which Weiner et al. acknow­ ough survey and Poole and Reed' a pre­ (Wiley. New York. 1980) . cise analysis, is of great importance. Some 17. Kessels. H.J . & Dungworth, G. in Biochemistry of Amino ledge. A modern rat tail and a seventeenth A cids (ed . Hare. P.E.) 527- 541 (Wiley . New York. 1980). century book cover do not provide a of the skins were found in the same cave, varied series, though the authors use them some scattered on the surface, others WEINER et at. reply-In our study, we re­ as comparative materials to the scroll sam­ buried and some appear to have been disc­ ported the development of a new method ples. An adequate sample basis must be overed several centuries ago and been for assessing the extent to which collagen developed on a wider range of material exposed to quite varied climatic con­ has transformed to gelatin in ancient 13 both ancient and modern; this could be ditions11- • parchments and we tried to estimate the accomplished by application of the tests Others were preserved for longer approximate time that elapsed since the on samples which have a known docu­ periods as whole scrolls rolled in and transformation took place. We applied mentation between the first and sixteenth placed in jars encased in tar. Varied hist­ these methods to the analysis of some 40 centuries AD which would include changes ories of the fragments should be listed and parchment fragments from the Dead Sea in parchment preparation both in referred to when discussing the results of Scrolls. We agree with Kahle and Caldar­ and the '-'. testing. Rapid deterioration can occur in aro that a thorough study, which includes When considering the condition of organic material transferred from one more background information on the materials found in the Qumran caves. it environment to another. Fragments taken pieces analysed as well as controlled stu­ may be of interest that most scholars, from the dry conditions in the caves to a dies of parchments of different ages, pre­ given the methods of examination at the humid environment or one with rapid or pared in various ways and subjected to a time, believed the two scrolls offered to frequent variation could cause severe and range of and condi­ the in the 1880's by M.W. immediate damage.lt is of interest to note tions, would be the most helpfuL Inciden­ Schapira to be forgeries based partly on that the authors are continuing their res­ tally, some of the background information the fact that their condition was through­ earch with specific attention to the clim­ can be ascertained from the literature us­ out so superlative compared to known atic effects of the transition of collagen to ing the information supplied in our Table fragments;. There is now little doubt that gelatin (S . Weiner, personal communica­ 1. We took care to emphasize in our ori­ the Schapira Scrolls came from the Dead tion). ginal publication that the transformation Sea caves". Given the problems with amino acid of collagen to gelatin may be only one of It is unfortunate that Weiner et at. did dating, especially the variation with several different degradative processes 1 17 not examine the agents of deterioration of regard to radiometric methods " , that occur in ancient parchments. Thus vellum to gelatin by controlled testing, examination of rates of decay from amino caution must be exercised when correla­ and then subject their samples to the acid oiL values should be considered very tions between some parchment property collagen/gelatin and oiL testing. Such test­ relative, especially with regard to natural and collagen:gelatin proportions and/or ing of modern and ancient samples (com­ and human interventions. Nevertheless, oiL ratios are made, as Kahle and Caldar­ bined with accelerated aging tests) would its use as a source of approximate time aro are suggesting. We also noted that the

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