f cross-referencing is invaluable to the organized mind. The
purpose of classifying one's information is not to show how much there
is, but to answer questions quickly and to guide constructive thinking.
A clipping that deals with _alcoholism_, _patent medicine_, and
_tuberculosis_ must be posted in three places, or cross-referenced;
otherwise it will be used to answer but one question when it might
answer three. If magazines may not be cut, it will be easy to record
the fact of a useful article by writing the title, page, and date on
the appropriate index card, or inclosing a slip so marked in the proper
envelope.

While it is true that the most important bibliography one can have in
his private library is a classification of the material of which he
himself has become a part while reading it, there are a number of
health journals that one can profitably subscribe for. In fact, it is
often true that the significant discoveries in scientific fields, or
the latest public improvements, such as parks, bridges, model
tenements, will not be appreciated until one has read in health
journals how these improvements affect the sickness rate and the
enjoyment rate of those least able to control their living conditions.
The physician and nurse in their educational work for hospitals are
distributors of health propaganda.

Wherever there is a local journal devoted to health, parents, teachers,
educators, and club leaders would do well to subscribe and to hold this
journal up to a high standard by quoting, thanking, criticising it. In
New Jersey, for example, is a monthly called the _New Jersey Review of
Charities and Corrections_ that deals with every manner of subject
having to do with public health as well as with private and public
morality and education.

A similar journal, intended for national instruction, is _The Survey_,
whose topical index for last year enumerates two hundred and thirty-two
articles dealing with subjects directly connected with public hygiene,
e.g.:

Schools, 6; school inspection, 3; eyes,--school children, 1; sex
instruction in the schools, 2; psychiatric clinic, special
children, 2; industrial education, 5; child labor, 18;
playgrounds, 26; alley, crap, playing in streets, 3; labor
conditions, 18; industrial accidents, 10; wage-earner's
insurance, 4; factory inspection, 1; consumer's league, 3; women's
work, 6; tuberculosis, 23; hospitals, dispensaries (social), 5;
tenement reform,