+527.+ The dash is a much abused punctuation mark. A great many writers
who are not familiar with the rules of punctuation use a dash whenever
they feel the need of some sort of a punctuation mark. Their rule seems
to be, "whenever you pause make a dash." Punctuation marks indicate
pauses but a dash should not be used upon every occasion. The dash
should not be used as a substitute for the comma, semi-colon, colon,
etc. In reality, the dash should be used only when these marks cannot be
correctly used.
+528.+ The chief use of the dash is to indicate a sudden break in the
thought or a sudden change in the construction of the sentence. For
example:
In the next place--but I cannot discuss the matter further under the
circumstances.
+529.+ The dash is frequently used to set a parenthetical expression off
from the rest of the sentence when it has not as close connection with
the sentence as would be indicated by commas. As for example:
The contention may be true--although I do not believe it--that this
sort of training is necessary.
+530.+ The dash is also used in place of commas to denote a longer or
more expressive pause. For example:
The man sank--then rose--then sank again.
+531.+ The dash is often used after an enumeration of several items as a
summing up. For example:
Production, distribution, consumption--all are a part of economics.
+532.+ A dash is often used when a word or phrase is repeated for
emphasis. For example:
Is there universal education--education for every child beneath the
flag? It is not for the masses of the children--not for the children
of the masses.
+533.+ If the parenthetical statements within dashes require punctuation
marks, this mark should be placed before the second dash. For example:
War for defense--and was there ever a war that was not for
defense?--was permitted by the International.
This sight--what a wonderful sight it was!--greeted our eyes with the
dawn.
+534.+ The dash is also used to indicate the omission of a word,
especially such words as _as_, _namely_, _viz._, etc. For example:
Society is divided into two classes--the exploited and the exploiting
classes.
+535.+ After a quotation, use the dash before the name of the author.
For example:
Life only avails, not the having lived.--_Emerson_.
+536.+ The dash is used to mark the omission of letters or figures. For
example:
It happened in the city of M--.
It was in the year 18--.