Capital letters are used to give emphasis to or call attention to certain words to distinguish them from the context. In manuscripts they may be written small or large and are indicated by lines drawn underneath, two lines for SMALL CAPITALS and three lines for CAPITALS.
Some authors, notably Carlyle, make such use of Capitals that it degenerates into an abuse. They should only be used in their proper places as given in the table below.

1.    The first word of every sentence, in fact the first word in writing of any kind should begin with a capital; as, "Time flies." "My dear friend."

2.    Every direct quotation should begin with a capital; "Dewey said,—'Fire, when you're ready, Gridley!'"

3.    Every direct question commences with a capital; "Let me ask you; 'How old are you?'"

4.    Every line of poetry begins with a capital; "Breathes there a man with soul so dead?"

5.    Every numbered clause calls for a capital: "The witness asserts: (1) That he saw the man attacked; (2) That he saw him fall; (3) That he saw his assailant flee."

6.    The headings of essays and chapters should be wholly in capitals; as, CHAPTER VIII—RULES FOR USE OF CAPITALS.

7.    In the titles of books, nouns, pronouns, adjectives and adverbs should begin with a capital; as, "Johnson's Lives of the Poets."

8.    In the Roman notation numbers are denoted by capitals; as, I II III V X L C D M—1, 2, 3, 5, 10, 50, 100, 500, 1000.

9.    Proper names begin with a capital; as, "Jones, Johnson, Caesar, Mark Antony, England, Pacific, Christmas."

Such words as river, sea, mountain, etc., when used generally are common, not proper nouns, and require no capital. But when such are used with an adjective or adjunct to specify a particular object they become proper names, and therefore require a capital; as, "Mississippi River, North Sea, Alleghany Mountains," etc. In like manner the cardinal points north, south, east and west, when they are used to distinguish regions of a country are capitals; as, "The North fought against the South."

When a proper name is compounded with another word, the part which is not a proper name begins with a capital if it precedes, but with a small letter if it follows, the hyphen; as "Post-homeric," "Sunday-school."

10.  Words derived from proper names require a Capital; as, "American, Irish, Christian, Americanize, Christianize."

In this connection the names of political parties, religious sects and schools of thought begin with capitals; as, "Republican, Democrat, Whig, Catholic, Presbyterian, Rationalists, Free Thinkers."

11.  The titles of honorable, state and political offices begin with a capital; as, "President, Chairman, Governor, Alderman."

12.  The abbreviations of learned titles and college degrees call for capitals; as, "LL.D., M.A., B.S.," etc. Also the seats of learning conferring such degrees as, "Harvard University, Manhattan College," etc.

13.  When such relative words as father, mother, brother, sister, uncle, aunt, etc., precede a proper name, they are written and printed with capitals; as, Father Abraham, Mother Eddy, Brother John, Sister Jane, Uncle Jacob, Aunt Eliza. Father, when used to denote the early Christian writer, is begun with a capital; "Augustine was one of the learned Fathers of the Church."

14.  The names applied to the Supreme Being begin with capitals: "God, Lord, Creator, Providence, Almighty, The Deity, Heavenly Father, Holy One." In this respect the names applied to the Saviour also require capitals: "Jesus Christ, Son of God, Man of Galilee, The Crucified, The Anointed One." Also the designations of Biblical characters as "Lily of Israel, Rose of Sharon, Comfortress of the Afflicted, Help of Christians, Prince of the Apostles, Star of the Sea," etc. Pronouns referring to God and Christ take capitals; as, "His work, The work of Him, etc."

15.  Expressions used to designate the Bible or any particular division of it begin with a capital; as, "Holy Writ, The Sacred Book, Holy Book, God's Word, Old Testament, New Testament, Gospel of St. Matthew, Seven Penitential Psalms."

16.  Expressions based upon the Bible or in reference to Biblical characters begin with a capital: "Water of Life, Hope of Men, Help of Christians, Scourge of Nations."

17.  The names applied to the Evil One require capitals: "Beelzebub, Prince of Darkness, Satan, King of Hell, Devil, Incarnate Fiend, Tempter of Men, Father of Lies, Hater of Good."

18.  Words of very special importance, especially those which stand out as the names of leading events in history, have capitals; as, "The Revolution, The Civil War, The Middle Ages, The Age of Iron," etc.

19.  Terms which refer to great events in the history of the race require capitals; "The Flood, Magna Charta, Declaration of Independence."

20.  The names of the days of the week and the months of the year and the seasons are commenced with capitals: "Monday, March, Autumn."

21.  The Pronoun I and the interjection O always require the use of capitals. In fact all the interjections when uttered as exclamations commence with capitals: "Alas! he is gone." "Ah! I pitied him."

22.  All noms-de-guerre, assumed names, as well as names given for distinction, call for capitals, as, "The Wizard of the North," "Paul Pry," "The Northern Gael," "Sandy Sanderson," "Poor Robin," etc.

23.  In personification, that is, when inanimate things are represented as endowed with life and action, the noun or object personified begins with a capital; as, "The starry Night shook the dews from her wings." "Mild-eyed Day appeared," "The Oak said to the Beech—'I am stronger than you.'"