om the margin. One inch to the right is
a good distance for successive subordinate headings. Use Roman numerals,
capital letters, Arabic numerals, and small letters to indicate the
comparative rank of ideas. When a heading runs over one line, use
hanging indention; that is, do not allow the second line to run back to
the left-hand margin, but indent it. Make the numerals and letters (_1_,
_A_, etc.) stand out prominently. The title of a theme should not be
given a numeral or letter.

Faulty indention:

Sources of energy which may be utilized when the coal
supply is exhausted are

I Rivers and streams, especially in mountain
districts
II The tides
III The heat of the sun

Correct hanging indention:

Sources of energy which may be utilized when the coal supply
is exhausted are

I Rivers and streams, especially in mountain
districts
II The tides
III The heat of the sun

=e. Ideas parallel in thought should be expressed in parallel form.= Nouns
and phrases including nouns are ordinarily used.

Faulty parallelism:
Advantages of a garden:
1 Profitable
2 It affords good exercise
3 Gives pleasure

Right:
Advantages of a garden:
1 Profit
2 Exercise
3 Pleasure

=f. Avoid faulty coordination (giving two ideas equal rank, when one
should be subordinated to the other) and _vice versa_, avoid faulty
subordination.=

Faulty coordination:

How Seeds Scatter

I By Wind
II Some Seeds provided with parachutes
III Others light, and easily blown about
IV By Water
V By Animals

Right:

=How Seeds Scatter=

I By Wind
A Some seeds provided with parachutes
B Others light, and easily blown about

II By Water

III By Animals

=g. Avoid detailed subordination. Especially avoid a single subheading
when it can be joined to the preceding line, or omitted.=

Too detailed:

A The McClellan Orchard
1 Situation
a On a northern slope
2 Nature of soil
a Sandy
3 Kind of fruit
a Apple
b Cherry

Right:

A The McClellan Orchard
1. Situation: a northern slope
2. Nature of soil: sandy
3. Kind of fruit: apple and cherry