That the field of Mossbauer spectroscopy continues for the remarks section of the index, and the inclusion to be an important growth area in science and tech- of some new appendices and tables (such as the en- nology, despite recent economic pressures, is ade- ergy conversion tables, nuclear radius and moment quately evidenced by the present volume. Covering re- data, and the report of the ASTM Task Group on search published only in the year 1969, its size is com- Mossbauer Nomenclature and Conventions). The parable to its predecessor, Mossbauer Effect Data advertisement section, too, provides a collection of Index 1958-1965. With such continuing growth in information useful to many readers. many fields, the need for specialized information re- In summary, the new editors are to be congratulated trieval tools for the research worker is now becoming for their excellent and tremendous effort in putting together such a fine compilation in a remarkably short an increasingly important internationally recognized time. The user community, I am sure, will strongly concern. MEDI 1969 satisfies much of this need for the community it addresses in a timely manner. urge them to continue this series, as I know their pred- This work not only follows in the footsteps of its ecessor has been urged to help fill the gap for the years 1966-1968.
predecessor, but also includes a number of important and very useful innovations. Among these are the classification of substances investigated according to ARTHUR H. MUIR, JR.