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Tree rings and climate
Jownal
of‘ Archaeological
Science 1977, 4, 391-399
Book Reviews
Tree Rings and Climate. By H. C. Fritts. 1977. xii+567
pp. London:
Academic Press. E16.00. The science of dendrochronology started with the work of Douglass at the turn of the century. He was the first to demonstrate crossdating of tree rings and to establish climatic correlations, though his ultimate reason for doing so was not climatology itself but sunspot activity. It was through the work of Douglass that dendrochronology was taken up by anthropologists and used successfully to build up a chronology by which it was possible to date the timbers from archaeological sites in south-western North America. Early on Douglass set up a Laboratory of Tree Ring Research at Tucson, and it is from this same stable that the present book comes. In his early days, when he was using dendrometry, Professor Fritts was not convinced of the climatological value of tree-ring research; he has clearly not only changed his view but has been largely responsible for the development of the science of dendroclimatology. As he explains, this development has been made possible by the rigorous application of statistical and calibration methods to tree-ring analysis, and what we have here is the first authoritative and comprehensive textbook on the subject. The book consists of nine chapters, four of which deal with the principles of botanical physiology and anatomy which are a necessary background to an understanding of the complex interaction between the various climatic factors, the tree itself and the actual laying down of the growth ring. Then follows a detailed coverage of the mensurational and statistical methodology of ring analysis, and the book concludes with examples of climatic interpretation and reconstruction based on tree ring data. No doubt the author did not intend the botanical background presented in the early chapters to be a comprehensive coverage of these subjects but rather a selection of material relevant to the particular theme of tree-ring analysis. This would explain why full treatment is not given to such topics as wood anatomy, but in this case what is given fails to draw attention to the specific variation of structure within both hardwoods and conifers. a factor which, conceivably, might be important to the dendrochronologist when using old timber separated from its living source. Another over-simplification is in the discussion of the functioning of the root, where it is not made clear that the connection between the root and the soil in forest trees normally involves mycorrhiza. The author has probably acquired most of his experience in dealing with conifers and this may account for the lack of emphasis on differences between conifers and hardwoods. Defoliation of evergreen conifers, for instance, which involves several years’ growth of needles, will have a more marked effect on stem growth than a similar episode in a deciduous hardwood. The author also seems to be under the misapprehension that bordered pits are only found in conifer wood. Such minor criticisms apart, this book must be hailed as a major contribution to the science of climatology and one that admirably fulfils the purpose for which it was written. It is quite unwarrantable to judge it on other grounds, but readers of this journal will want to know how relevant it is to archaeology. Saying that it is only of marginal value in this field, therefore, implies no criticism of the book or its author. As mentioned above, archaeology early became connected with tree-ring dating, and in more recent 391
392
BOOK REVIEWS
times the building up of the bristlecone pine (the Great Basin form of which we now have to call Pinus longaeva) chronology and its use for the calibration of radiocarbon dating have become familiar to all archaeologists. Fritts does not even mention this use of dendrochronology and only refers to archaeology en passant, although in Europe archaeological sites are an important source of dendrochronological material. Indeed, the examples of climatic reconstructions he gives seldom go back further than three centuries. Much of his work is designed to provide a background of climatic pattern against which present-day changes can be seen and from which future trends might be projected. The book is well produced, well illustrated and very fully referenced, with adequate attention to European as well as American sources. G. W. Dimbleby
A Dictionary of Earth Sciences. Edited by Stella E. Stiegeler. 1976. 301 pp. London: The Macmillan Press. $595. Like most technical dictionaries which set out to cover a broad field, A Dictionary of Earth Sciences edited by Stella E. Stiegeler presents a rather uneven coverage of the field. Since there is already A Dictionary of Life Sciences in the same series few biological terms are defined. Surprisingly perhaps, ecosystem is not included, nor are such biological concepts as productivity and biomass. Since soils are included there is an entry for humus but no further entries for its constituents lignins and polysaccharides. Cationic exchange merits an entry, but not ions or anions. The index of a recently published work on archaeology and earth sciences provides a useful test of how helpful this particular dictionary is likely to prove to an archaeological reader. Of the first twenty technical terms listed in the index only eight are to be found in the dictionary. While there is an entry under particle size which includes the British Standards Classification of Particle Sizes there is nothing to help a reader discover the meaning of the p (phi) scale. Traditional methods for displaying data such as triangular diagrams and cumulative percentage curves are nowhere explained. There is an entry for linkage analysis but not for factor analysis. Generally techniques are not described so that the archaeological reader who finds such commonly used techniques as spectrography and electron microscopy referred to in technical reports on excavated materials, will have to look elsewhere for information. There is an entry under radiometric dating but no mention of 14C, potassium-argon, or oxygen isotopes. The definitions seem generally satisfactory and the coverage acceptable for basic geomorphic features, common minerals, elementary geologic terms including newer terms in plate tectonics, weather and climate, and morphological features of soils. Overall the usefulness of this dictionary to archaeologists is likely to be limited. Illustrations are few and there are no references for further reading. A good introductory textbook on physical geography or earth sciences is likely to be more useful. Bruce Proudfoot
Hillforts. Later Prehistoric Earthworks in Britain and Ireland. Edited by D. W. Harding. 1976. xiv + 579 pp. Illustrations. Index. London: Academic Press. &24-00. This massive volume contains a sixty page introductory chapter by Michael Avery on hillforts in general, twelve reports of varying lengths on individual hillforts, and regional
of‘ Archaeological
Science 1977, 4, 391-399
Book Reviews
Tree Rings and Climate. By H. C. Fritts. 1977. xii+567
pp. London:
Academic Press. E16.00. The science of dendrochronology started with the work of Douglass at the turn of the century. He was the first to demonstrate crossdating of tree rings and to establish climatic correlations, though his ultimate reason for doing so was not climatology itself but sunspot activity. It was through the work of Douglass that dendrochronology was taken up by anthropologists and used successfully to build up a chronology by which it was possible to date the timbers from archaeological sites in south-western North America. Early on Douglass set up a Laboratory of Tree Ring Research at Tucson, and it is from this same stable that the present book comes. In his early days, when he was using dendrometry, Professor Fritts was not convinced of the climatological value of tree-ring research; he has clearly not only changed his view but has been largely responsible for the development of the science of dendroclimatology. As he explains, this development has been made possible by the rigorous application of statistical and calibration methods to tree-ring analysis, and what we have here is the first authoritative and comprehensive textbook on the subject. The book consists of nine chapters, four of which deal with the principles of botanical physiology and anatomy which are a necessary background to an understanding of the complex interaction between the various climatic factors, the tree itself and the actual laying down of the growth ring. Then follows a detailed coverage of the mensurational and statistical methodology of ring analysis, and the book concludes with examples of climatic interpretation and reconstruction based on tree ring data. No doubt the author did not intend the botanical background presented in the early chapters to be a comprehensive coverage of these subjects but rather a selection of material relevant to the particular theme of tree-ring analysis. This would explain why full treatment is not given to such topics as wood anatomy, but in this case what is given fails to draw attention to the specific variation of structure within both hardwoods and conifers. a factor which, conceivably, might be important to the dendrochronologist when using old timber separated from its living source. Another over-simplification is in the discussion of the functioning of the root, where it is not made clear that the connection between the root and the soil in forest trees normally involves mycorrhiza. The author has probably acquired most of his experience in dealing with conifers and this may account for the lack of emphasis on differences between conifers and hardwoods. Defoliation of evergreen conifers, for instance, which involves several years’ growth of needles, will have a more marked effect on stem growth than a similar episode in a deciduous hardwood. The author also seems to be under the misapprehension that bordered pits are only found in conifer wood. Such minor criticisms apart, this book must be hailed as a major contribution to the science of climatology and one that admirably fulfils the purpose for which it was written. It is quite unwarrantable to judge it on other grounds, but readers of this journal will want to know how relevant it is to archaeology. Saying that it is only of marginal value in this field, therefore, implies no criticism of the book or its author. As mentioned above, archaeology early became connected with tree-ring dating, and in more recent 391
392
BOOK REVIEWS
times the building up of the bristlecone pine (the Great Basin form of which we now have to call Pinus longaeva) chronology and its use for the calibration of radiocarbon dating have become familiar to all archaeologists. Fritts does not even mention this use of dendrochronology and only refers to archaeology en passant, although in Europe archaeological sites are an important source of dendrochronological material. Indeed, the examples of climatic reconstructions he gives seldom go back further than three centuries. Much of his work is designed to provide a background of climatic pattern against which present-day changes can be seen and from which future trends might be projected. The book is well produced, well illustrated and very fully referenced, with adequate attention to European as well as American sources. G. W. Dimbleby
A Dictionary of Earth Sciences. Edited by Stella E. Stiegeler. 1976. 301 pp. London: The Macmillan Press. $595. Like most technical dictionaries which set out to cover a broad field, A Dictionary of Earth Sciences edited by Stella E. Stiegeler presents a rather uneven coverage of the field. Since there is already A Dictionary of Life Sciences in the same series few biological terms are defined. Surprisingly perhaps, ecosystem is not included, nor are such biological concepts as productivity and biomass. Since soils are included there is an entry for humus but no further entries for its constituents lignins and polysaccharides. Cationic exchange merits an entry, but not ions or anions. The index of a recently published work on archaeology and earth sciences provides a useful test of how helpful this particular dictionary is likely to prove to an archaeological reader. Of the first twenty technical terms listed in the index only eight are to be found in the dictionary. While there is an entry under particle size which includes the British Standards Classification of Particle Sizes there is nothing to help a reader discover the meaning of the p (phi) scale. Traditional methods for displaying data such as triangular diagrams and cumulative percentage curves are nowhere explained. There is an entry for linkage analysis but not for factor analysis. Generally techniques are not described so that the archaeological reader who finds such commonly used techniques as spectrography and electron microscopy referred to in technical reports on excavated materials, will have to look elsewhere for information. There is an entry under radiometric dating but no mention of 14C, potassium-argon, or oxygen isotopes. The definitions seem generally satisfactory and the coverage acceptable for basic geomorphic features, common minerals, elementary geologic terms including newer terms in plate tectonics, weather and climate, and morphological features of soils. Overall the usefulness of this dictionary to archaeologists is likely to be limited. Illustrations are few and there are no references for further reading. A good introductory textbook on physical geography or earth sciences is likely to be more useful. Bruce Proudfoot
Hillforts. Later Prehistoric Earthworks in Britain and Ireland. Edited by D. W. Harding. 1976. xiv + 579 pp. Illustrations. Index. London: Academic Press. &24-00. This massive volume contains a sixty page introductory chapter by Michael Avery on hillforts in general, twelve reports of varying lengths on individual hillforts, and regional