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 variety of uses.  In such expository passages the transition and connecting words are mainly expressions of place and relative position such as to the right, above, below, to the rear, extending upwards at an angle of sixty degrees, dividing equally into three sections. Such indications must never be slighted in spoken explanations.  They keep the material clear and exact in the hearer’s comprehension.  The speaker, remember, can never assume that his audience is bound to understand him.  His task is to be so clear that no single individual can fail to understand him.

Importance.  It has already been stated—­in the chapter on planning—­that topics may be arranged in the order of their importance.  This same scheme may be used in delivery of expository matter.  A hearer will follow the explanation if he be led gradually up the ascent; he will remember most clearly the latter part of the passage.  If this include the prime factor of the information he will retain it longest and most clearly.  You should listen to speeches of explanations critically to judge whether the plans are good.  Should you make a list of the number of times any of the plans here set down appears you will be struck by the fact that while other orders are quite frequent, this last principle of leading up to the most important outranks all the others.  It may be simply a form of one of the others previously enumerated in which time order, or contrast, or cause to effect is followed simply because that does bring the most important last in the discussion.  Such an arrangement answers best to the response made to ideas by people in audiences.  It is a principle of all attempts to instruct them, to appeal to them, to stimulate them, to move them, that the successive steps must increase in significance and impressiveness until the most moving details be laid before them.  Analyze for yourself or for the class a few long explanations you have listened to, and report whether this principle was followed.  Does it bear any relation to concluding a speech with a peroration?