THIS ROOK. uhich describes the interactions betasen clay particles and organic matter (polymers) in waters IS a welcome. if expensive. addition to the Elsevier series on Soil Science. and provides an extensive review of the literature on virtually all aspects of the interactions betvvsen organics and particulates up to the end of 1976. Pwr I C1tr.r rt~irrcruls curd polprnt~ udsorptio~ is devoted to a summary of some of the more important features of clays. such as their structure and swelling properties and to the theory of the adsorption of polymers onto their surfaces. Ptrrr II Inrerclcriorts of da! mirrc~rtrls wirh s~urlreric pd_wwrs includes sections on uncharged. negativelyand positively-charged polymers and also one in the practical applications of clay-polymer interactions. Purr 111 /rtrcwction.s of thy miwrtrls wiflr rrurtrrully occtrrriwg pol,,nrvrs is the longest section in the book and is concerned wtth the interactions of clays and organic-substances uhtch arc known to form part of naturally occurring polymers (humics). Substances covered in the text include proteins, cnzymcs. nucleic acids. nucleoprotcins. viruses and polysaccharidcs. The author has condensed together a great deal of information into one volume, and sometimes even into a single paragraph. Because of this, it is inevitable that some fcatures are over-condensed. For example, the influence of pH on the shape and size of fulvic acid (FA) fibres is mentioned in the middle of a page (301) on which is described the interlayer uptake of FAs and humic acids (HAS) by
minerals and is immediately followed by the remark that it is not certain whether or not such shape and size of FAs is maintained in aqueous solution. Such findings have only a peripheral interest to the particular subject. but then so has practically everything else in the book. This quantity of detailed information and the style of writing (continuously referring to sources) make large sections of the book very difficult to read. Possibly more use could have been made of tables to provide a schematical reference storage. Personally I would have preferred more thorough comparison of forces which determine the adsorption of natural organics onto clays. rather than using space for the section on syntnetics. For example. although it is concluded that for humics Coulombic forces predominate in the adsorption process. insuflicirnt importance is given to. for example. van der Waals forces in solutions of increased ionic strength. or to entropy for large molecules. In general. the book does represent a very good effort both to combine the vast amount of information on the subject of clay-organics interactions. and to make this information culminate in an explanation of these interactions. Having a subject index and an author index in the back, and lists of references at the end of each chapter. the book should be a good source of references and it may not age very quickly, since the field does not seem to move ahead very rapidly.
CONSTANT M. G. VAN DES BEN; Drpcwtmenr of Oceunoyrtrplt~ Thr Urtirersir~ of Liwrpool P.O. Bos 117 Liwrpool L6Y 3BX. LX.