Verse appeals to the ear by its melodious combinations of sounds and also by the regular recurrence of similar sounds in _rhymes_. These usually occur at the ends of verses. In order that a rhyme may be perfect the two rhyming syllables must both be accented, the vowel sound and the consonants following must be identical, and the sounds preceding the vowel must be different. For example, _fate_ and _late_ rhyme; _fat_ and _late_ do not; _fate_ and _lame_ do not; _debate_ rhymes with _relate_, but not with _prelate_. Double rhymes occur frequently, as in the words _bowlders, shoulders_. Take this stanza from Hood's _Song of the Shirt_: With fingers weary and worn, With eyelids heavy and red, A woman sat in unwomanly rags Plying her needle and thread-- Stitch! Stitch! Stitch! In poverty, hunger and dirt; And still with a voice of dolorous pitch She sang the "song of the shirt." Here the first and third lines are unrhymed, the second and fourth, the fifth and seventh, and the sixth and eighth lines rhyme alternately in couplets. If the beginnings of the verses are noticed it will be seen that the indentations of the lines correspond with the rhymes. Rhymes are not always used in poetry. Most of Shakespeare's plays are written in _blank verse_, which is unrhymed iambic pentameter, called _heroic verse_. _Hiawatha_ and _Evangeline_ are not rhymed, the former being trochaic tetrameter and the latter largely dactylic hexameter. Frequently appeal is made to the ear by a similarity of sound at the beginning of words. This is known as _alliteration_. In early English poems this was of prime importance and subject to rigid rules, but more recently it has been used without rule, subject merely to the author's will. This is seen to a marked degree in many writers. Here are several lines taken from Poe's _The Bells_: What a world of _m_erriment their _m_elody foretells, What a _t_ale of _t_error now their _t_urbulency _t_ells. In a mad expostulation with the dea_f_ and _f_rantic _f_ire. In many cases alliteration is very skilfully handled, as where Whittier uses the liquid consonants to make more smooth and harmonious to the ear the line that tells the friendliness of the brooklet whose murmurings could not be heard in winter, but-- "The music of whose _li_quid _li_p Had been to us companionship" during the long summer days. The number of verses in a stanza varies from two to an indefinite number. When there are two verses the stanza is called a couplet; a three line stanza is called a tercet; a four line stanza, a quatrain. The five line stanza is not common, but six is a frequent number. _Kinds of Poetry_ Poems may be classified as epic, lyric and dramatic.