Contact and Frictional Electrification. W. R. Harper. Oxford University Press, New York, 1967. xii + 369 pp., illus. $11.20. Monographs on the Physics and Chemistry of Materials

opened up by the electron microscope. The book therefore covers a field more familiarly known as molecular biology. The book is well made; almost all the electron micrographs are excellently reproduced. The overall coverage, though broad, is uneven. The subject of lipids and membranes, the author's principal interest, is covered in extenso; it is unfortunate that the present vigorous research activity relating to membranes and the conformation of proteins within membranes should have arisen while the book was being written or after. The subject of mineralization and calcification is presented succinctly and well, and its treatment fills a gap which many books of this nature have left open. The subject of striated muscle is well covered in an up-to-date manner, although little is said of smooth muscle. Nothing is said about the mitotic apparatus, although an attempt is made to resolve the present complicated picture of the mammalian chromosome structure. The structure and conformation of collagen and elastin are discussed in some detail, but no mention of cross-linking is made with respect to either protein. The structure and function of enzymes are discussed, allosterism is mentioned, and the chapter is brought right up to date by the example of the interaction of lysozyme with its substrate as defined by recent x-ray data, but no mention is made of feedback inhibition. The book includes a summary of methods of ultrastructure research, and here too the coverage is uneven. The subject of x-ray investigation is covered in a very broad manner; in many cases the breadth exceeds that necessary to give an appreciation of the power and limitations of the method, which surely is the justification for presenting the topic. By contrast, ultracentrifugation is barely mentioned, and although electron microscopy is covered in some detail, little reference is made to freeze etching and none to the scanning microscope. The book is intended for students as well as research workers in molecular biology, and for the needs of the former the chapters close with lists of wellchosen sources for further reading. For the research worker the lack of direct reference for many of the statements in the text is annoying; some snippets of information are given which a worker might well wish to pursue, but no reference or comment on authors is given to aid in the identification. Some such