other purposes of explanation. It is excellently suited
to historical material, or any related kind. It is the device usually
employed in explaining mechanical or manufacturing processes. In mere
frequency of occurrence it is doubtlessly the most common.

Time Order Reversed. The student who starts to cast his expositions
into this scheme should judge its fitness for his particular purpose
at the time. It will often become apparent upon thought that instead
of the natural chronological order the exact opposite will suit
better. This--time order reversed--explains itself as the arrangement
from the latest occurrence back through preceding events and details
until the earliest time is reached. It is quite like the arrangement
from effect back to cause. It might be used to explain the legal
procedure of a state or nation, to explain treaty relations, to
explain the giving up of old laws. The movements of a man accused of
crime might be explained in this way. An alibi for a person might be
built up thus. The various versions of some popular story told over
and over again through a long period of years might be explained after
such a manner.

Although the time order reversed is not so common as the chronological
order it does occur many times.

Place. Certain material of exposition demands the order of place. This
means that the details of the explanation are arranged according to
the position of objects. If you have written many descriptions you
are familiar with the problems brought up by such an order. A few
illustrations will make it clear. A man on the street asks you how to
reach a certain point in the city. On what plan do you arrange your
directions? According to their place? You start to explain to a friend
the general lay-out of New York, or Chicago, or San Francisco. How do
you arrange the details of your exposition? You attempt to convey to
another person the plan of some large building. What arrangement is
inevitable? How do books on sports explain the baseball field, the
football gridiron, the tennis court, the golf links? When
specifications for a building are furnished to the contractor, what
principle of arrangement is followed? If an inventor gives
instructions to a pattern-maker for the construction of a model, what
plan does he follow? Would a man discussing drawings for a new house
be likely to formulate his explanations on this scheme?

You see, then, how well suited such an arrangement is to a var