Caesar reported to the Senate, "I came, I saw, I conquered."

The question is, What shall we do next?

10. To indicate the omission of the verb in compound sentences having a common verb in several clauses.

One man glories in his strength, another in his wealth, another in his learning.

11. To separate phrases containing the case absolute from the rest of the sentence.

The form having been locked up, a proof was taken.

12. Between words or phrases in apposition to each other.

I refer to DeVinne, the great authority on Printing.

The comma is omitted when such an apposition is used as a single phrase or a compound name.

The poet Longfellow was born in Portland.

The word _patriotic_ is now in extensive use.

13. After phrases and clauses which are placed at the beginning of a sentence by inversion.

Worn out by hard wear, the type at last became unfit for use.

Ever since, he has been fond of celery.

The comma is omitted if the phrase thus used is very short.

Of success there could be no doubt.

14. Introductory phrases beginning with _if_, _when_, _wherever_, _whenever_, and the like should generally be separated from the rest of the sentence by a comma, even when the statement may appear to be direct.

When a plain query has not been answered, it is best to follow copy.

If the copy is hard to read, the compositor will set but few pages.

15. To separate introductory words and phrases and independent adverbs from the rest of the sentence.

Now, what are you going to do there?

I think, also, Franklin owed much of his success to his strong common sense.

This idea, however, had already been grasped by others.

Of course the comma is not used when these adverbs are used in the ordinary way.

They also serve who only stand and wait.

This must be done, however contrary to our inclinations.

16. To separate words or phrases of direct address from the context.

I submit, gentlemen, to your judgment.

From today, my son, your future is in your own hands.

17. Between the name of a person and his t.i.tle or degree.

Woodrow Wilson, President of the United States.

Charles W. Eliot, LL.D.

18. Before the word _of_ connecting a proper name with residence or position.

Senator Lodge, of Ma.s.sachusetts.

Elihu B. Root, Senator from New York.

19. After the salutatory phrase at the beginning of a letter, when informal.

Dear John,

When the salutation is formal a colon should be used.

My dear Mr. Smith:

20. To separate the closing salutation of a formal letter from the rest of the sentence of which it forms a part.

Soliciting your continued patronage, I am, Very sincerely yours, John W. Smith.

21. To separate two numbers.

January 31, 1915.

By the end of 1914, 7062 had been built.

22. To indicate an ellipsis.

Subscription for the course, one dollar.

Exceptions to this rule are made in very brief sentences, especially in advertis.e.m.e.nts: Tickets 25 cents. Price one dollar.

The foregoing rules for the use of the comma have been compiled from those given by a considerable number of authorities. Further examination of authorities would probably have added to the number and to the complexity of these rules. No two sets of rules which have come under the writer's observation are alike. Positive disagreements in modern treatises on the subject are few. The whole matter, however, turns so much on the use made of certain general principles and the field is so vast that different writers vary greatly in their statements and even in their ideas of what ought to be stated. It is very difficult to strike the right mean between a set of rules too fragmentary and too incomplete for any real guidance and a set of rules too long to be remembered and used.

After all possible has been done to indicate the best usage it remains true that the writer or the printer must, in the last resort, depend very largely on himself for the proper application of certain principles. The compositor may find himself helped, or restricted, by the established style of the office, or he may at times be held to strict following of copy. When left to himself he must be guided by the following general principles:

I. The comma is used to separate for the eye what is separate in thought.

The comma is not intended to break the matter up into lengths suited to the breath of one reading aloud.

The comma is not an aesthetic device to improve the appearance of the line.

II. The sole purpose of the comma is the unfolding of the sense of the words.

III. The comma cannot be correctly used without a thorough understanding of the sense of the words.

IV. In case of doubt, omit the comma.