1.  Never write for the purpose of using figures of speech.  Nearly everything that we need to say can be well expressed in plain, bare English, and the ability to express our thoughts in this way is the essential thing.  If a figure that adds to the force and clearness of your expression occurs to you, use it without hesitation.  A figure may also add to the beauty of our expression.  The examples to be found in literature are largely of this character.  If well used, they are effective, but the beginner should beware of a figure that is introduced for decorative purposes only.  An attempt to find figures of speech in ordinary prose writing will show how rarely they are used.

2.  The figures should fit the subject in hand.  Some comparisons are appropriate and some are not.  If the writer is familiar with his subject and deeply in earnest, the appropriate figures will rise spontaneously in his mind.  If they do not, little is gained by seeking for them.

3.  The effectiveness of a comparison, whether literal or figurative, depends upon the familiarity of the reader with one of the two things compared.  To say that a petrel resembled a kite would be of no value to one who knew nothing of either bird.  Similarly a figure is defective if neither element of the comparison is familiar to the readers.

4.  Suitable figures give picturesqueness and vivacity to language, but hackneyed figures are worse than none.

5.  Elaborate and long-drawn-out figures, or an overabundance of short ones, should be avoided.

6.  A figure must be consistent throughout.  A comparison once begun must be carried through without change; mixing figures often produces results which are ridiculous.  The “mixed metaphor” is a common blunder of beginners.  This fault may arise either from confusing different metaphors in the same sentence, or from blending literal language with metaphorical.  The following will serve to illustrate:—­

1. [Confused metaphor.] Let us pin our faith to the rock of perseverance and honest toil, where it may sail on to success on the wings of hope.

2. [Literal and figurative blended.] Washington was the father of his country and a surveyor of ability.

3.  When the last awful moment came, the star of liberty went down with all on board.

4.  The glorious work will never be accomplished until the good ship “Temperance” shall sail from one end of the land to the other, and with a cry of “Victory!” at each step she takes, shall plant her banner in every city, town, and village in the United States.

5.  All along the untrodden paths of the future we see the hidden footprints of an unseen hand.

6.  The British lion, whether it is roaming the deserts of India, or climbing the forests of Canada, will never draw in its horns nor retire into its shell.

7.  Young man, if you have the spark of genius in you, water it.