The editors of the new edition of "McGraw-Hill Encyclopedia of Science and Technology" state their goal succinctly: "This encyclopedia presents pertinent information in every field of modern science and technology." How do the editors define "every field," how do they organize pertinent information, and how clearly do they present it?
It turns out that "every field of modern science and technology" means the physical sciences and most of the biological sciences, but virtually excludes the social sciences other than psychology. Sociology, economics, and political science are omitted; archeology is treated briefly; and the articles on anthropology and linguistics focus on physical anthropology and psycholinguistics respectively, while cultural anthropology and comparative linguistics are excluded.
A similar emphasis extends to the biological sciences, in that behavioral biology receives scant coverage. For instance, nearly as many pages are devoted to the physiology and anatomy of one organ system alone (the cardiovascular system) as to the whole fields of sociobiology, ethology, behavioral ecology, animal behavior, and reproductive behavior combined. It would appear that the arguments between "hard scientists" and "soft scientists" common in academia were also fought out on the encyclopedia's board of editors, leaving the hard scientists victorious. But, it's possible to have both hard and soft science in the same encyclopedia--if that's what you want.
Pertinent information is organized by a "zoom lens" approach that leads from the new, most elementary introduction to increasingly detailed and advanced treatments. Each long article begins with a clear, one-sentence, dictionarylike definition, such as "Alicyclic hydrocarbon. Organic compounds containing only carbon and hydrogen atoms joined to form one or more rings." A few more sentences or paragraphs then provide basic background about what the topic consists of, what other topics it is related to, and why it is important. The rest of the article is divided into chunks identified by headings. Within a whole field like electrical power engineering, there are broad survey articles ("electricity," "electric power systems") and more specialized articles ("power-factor meter," "transmission lines"). Most articles conclude with a bibliography of relevant detailed publications.
Thus, readers of diverse backgrounds can all select material of an appropriate level: Neophytes can stop reading, and specialists can start reading, wherever is suitable for them. This system provides a neat compromise solution to the dilemma posed by a diverse readership.
Another neat compromise solution was found for the dictionary-vs.-textbook dilemma. There are few entries shorter than a generous paragraph, and few longer than 20 pages. Instead, the average entry is about 1 1/2 pages long, and there are about 7,700 entries in all. To avoid the risk of lack of cohesion inherent in this "medium-length" solution, the editors supply copious cross-referencing and indexing. Sprinkled throughout the text of each article are italicized cross-references to related articles. Most of Volume 20 consists of two independent indices: a "topical index" that lists all the entries for 27 broad subjects (e.g., the 213 entries on different areas of astronomy), and an "analytical index" that lists all entries relevant to 150,000 terms. The topical index is like the tables of contents for 77 textbooks, while the analytical index is like a dictionary with page references to the definitions.
All this pertinent information is presented clearly and readably, and the visual layout of the text is outstanding. Different typefaces for different levels of headings and for cross-references, wide side-margins (nearly 2 inches), and cleanly spaced text lines all help avoid eye strain. Fifteen thousand well-designed illustrations, many of them colored, depict anything from the typical arrangement of a 200-cow barn to the collapse of the Peruvian anchovy fishing industry. Sixty-nine beautiful color plates are thrown in as a visual bonus, but they contribute almost nothing to the overall didactic value, as there are fewer than one per 100 entries, and they are not even specifically mentioned in the text.
The authors of the text--more than 3,000 of them, each an expert on the topic he/she drafted--represent a Who's Who of American science. Although scientists tend not to be noted for their literary skills, the editors evidently massaged the resulting contributions to make them not only authoritative but clear and sometimes even lively and humorous. For example, to appreciate the problems that archeologists face in interpreting the objects they dig up, readers are asked to imagine future archeologists classifying modern societies by the form of the metal springs of our clothespins, long after the wooden parts have rotted away and long after the function of a clothespin has been forgotten!