These four titles all expand upon the second editions, released in 1988-89; each adds between 200 and 300 terms to keep the contents current, bringing the total number of entries up to approximately 3000 per volume. As in the previous editions, the definitions are concise and readable, targeted to the high school or undergraduate science student. Definitions range in length from a few lines in most cases to several paragraphs for more important or abstract terms. As with most technical dictionaries, etymological or pronunciation information is not provided, though line drawings enhance several of the definitions (approximately 50 per dictionary, double that in Mathematics). The use of British spellings, a drawback to the previous editions, has been eliminated here. Daintith, editor of three of the volumes, is a former research chemist in Great Britain. He is joined by Hine (life science editor of the Larousse Encyclopedia), science writer and editor Clark, and approximately a dozen contributors per dictionary. Each dictionary is supplemented by appropriate appendixes: taxonomic tables and amino acids (Biology); a periodic table, elemental information, fundamental particles, and constants (Chemistry); much the same for Physics; and conversion factors and useful symbols, formulae, and powers and roots (Mathematics). These are fine first references for the most common terms and concepts in their fields, filling a niche at the low-cost end of the market just above most concise subject dictionaries. Recommended for high school and undergraduate libraries.