Langmuir, one of the most prominent scientists of the 20th century and a Nobel Prizewinner for chemistry, has been featured in various collective biographies (e.g. Asimov's Breakthroughs in Science); this, however, is not only the first full-length juvenile, it is also eminently readable--an exciting story interestingly told. Apart from the usual excursions into aspects of his education, his research, his acquaintances, the author does a good deal to further the understanding and approval of science in our culture. Langmuir, freed of commercial bounds in the General Electric laboratories (a phenomenon common in the sciences), discovers many things which benefit his sponsor in ways that specifically oriented research is not prone to do. The moral: what is worth doing basic research upon has pragmatic potential also. A fine amalgam of information and enlightenment.