The ""two women scientists"" of the subtitle are Elizabeth Hazen (1885-1975) and Rachel Brown (1898-1980); their discovery is the antifungal drug, nystatin. A promising conjunction, there, of the exceptional and the little-explored--but despite the wealth of documentary and personal data at journalist Baldwin's disposal, this is a dry and distant accounting, and ill-proportioned besides. Fungal diseases, we're reminded, are often misdiagnosed and mistreated; in 1977 at least 688 Americans died of them, yet little systematic research is even now underway. The situation was even worse in 1931 when Augustus Wadsworth, director of the New York State Department of Health laboratories, hired microbiologist Hazen to work, in Manhattan, on fungal diseases--five years after hiring chemist Brown. (How Wadsworth came to be especially keen on women scientists--he hired many of them--Baldwin unfortunately doesn't tell us.) Searching for antifungal substances in soil samples, Hazen obtained an active preparation which, with Gilbert Dalldorf (who succeeded Wadsworth), she took to Brown in Albany. An unusual collaboration began: the two women worked in labs 150 miles apart and exchanged their experimental materials by mail (no shipment was ever lost). By 1950 they had isolated a nontoxic antifungal substance, dubbed ""nystatin"" in honor of the Empire state, which they leased to Squibb (where it was labeled ""mycostatin"") for bulk production and marketing; it cured patients, killed mildew on Old Masters, and prevented Dutch elm disease. Though spurred by Dalldorf to patent the discovery, both women refused any personal profit, instead using their royalties to set up the Brown-Hazen fund to foster mycological research. Half the book consists, indeed, of meticulous detail on the fund's operations--where a few examples would have sufficed. More crucial, however, is Baldwin's failure to invest either of these singular women with a personality, or to convey their special perspective on the male-dominated research environment. Given the potential, a misfire; and in itself largely indigestible.