Social, economic, and popular scientific trends converged in the early twentieth century to support the mass popularity of cosmetics. Twentieth-century magazine ads for personal care and beauty products reflected the contemporary belief that "science" was on the verge of being able to cure almost anything, including physical flaws and aging, and conveyed the imperative that "science" was ready to transform cosmetics users' lives if they would only let it. The prevailing themes of the time of individualism, materialism, and egalitarianism had an impact on the national attitude toward beauty and cosmetics. Also, a variety of trends can be ascribed to the growth of the cosmetic industry, such as: (1) the spread of beauty parlors; (2) women's new assertiveness; (3) the growth of the pleasure ethic; and (4) savvy beauty entrepreneurs. Beauty and personal care products industries made extensive use of magazine ads, where cosmetic advertisers enticed their female public with quasi-scientific gadgets and terms. It appears that cosmetic advertising may have both reflected and reinforced (i.e. legitimized) the popular cultural concept of "scientific" progress and improvement. Though the mystique of specialized knowledge certainly did not arise in this era, its aura was used to such advantage by advertisers that the technique has survived to the present day. (Ten figures and 97 notes are included.) (MS)