tilated.
6. What is meant by the theory of evolution.
7. The manufacture of ----.
8. How to make a ----.

(Consider the arrangement of your statements.)

+157. Use of an Outline.+--Before beginning to write an explanation we
need to consider what we know about the subject and what our purpose is;
we need to select facts that will make our explanations clear to our
readers; and we need to decide what arrangement of these facts will best
show their relation to each other. We shall find it of advantage,
especially in lengthy explanations, to express our thoughts in the form of
an outline. An outline helps us to see clearly whether our facts are well
chosen, and it also helps us to see whether the arrangement is orderly or
not. Clearness is above all the essential of exposition, and outlines aid
clearness by giving unity and coherence.

EXERCISES

Select three of the following subjects and make lists of facts that you
know about them. From these select those which would be necessary in
making a clear explanation of each. After making out these lists of facts,
arrange them in what seems to you the best possible order for making the
explanation clear to your classmates.

1. The value of a school library.
2. Sponges.
3. The manufacture of clocks.
4. Drawing.
5. Athletics in the high school.
6. Examinations.
7. Debating societies.

+Theme LXXXVII.+--_Following the outline, write an exposition on one of
the subjects chosen._

(Notice the transition from one paragraph to another. See Section 87.)

+158. Exposition of Terms--Definition.+--Explanation of the meaning of
general terms is one form of exposition (Section 63). The first step in
the exposition of a term is the giving of a definition. This may be
accomplished by the use of a synonym (Section 64). We make a term
intelligible to the reader by the use of a synonym with which he is
familiar; and though such a definition is inexact, it gives a rough idea
of the meaning of the term in question, and so serves a useful purpose.
If, however, we wish exactness, we shall need to make use of the logical
definition.

+159. The Logical Definition.+--The logical definition sets exact limits
to the meaning of a term. An exact definition must include all the members
of a class indicated by the term defined, and it must exclude everything
that does not belong to that class. A logical definition is composed of
two parts. It first names the