Erratum.
In the article "String as a theory of everything" by M. Mitchell Waldrop (Research News, 20 Sept., p. 1251), the last line of the first column was inadvertantly omitted. The affected sentence should have read, "Not only were the strong interactions far more complex than predicted by field theory, but the particles that participated in the strong interactions-the hadrons, a group that includes protons, neutrons, pi mesons, and many others-seemed to be relatively large, extended objects as much as 1 Fermi across (10(-13) centimeter)." In the next-to-the-last line of the second full paragraph in column 2 on page 1252, 10(-19) should have been 10(+19). Finally, the words "quandary" (page 1251, column 1, paragraph 6, line 2) and "quark" (page 1252, column 3, last paragraph, line 18) were misspelled.