“…The literature covering the vast field of cosmetics is almost appalling in its magnitude, but relatively little of it is of definite value. It can be divided into three groups, corresponding to the divisions in the industry: (1) trade publications, largely subsidized by manufacturers and advertisers, which, although many of them are of a much higher level now than formerly, are viewed with suspicion by the scientific investigators; (2) publications by medical authorities, textbooks on pharmacology, hygiene, etc., which, being based largely on "trouble cases," magnify the unfavorable aspects of the industry; (3) textbooks on cosmetology (for trade and industrial schools), bulletins of State or City Boards of Health or Education, in districts where beauty culture education and practice are controlled by law.…”