“The word metaphor derives from the Greek verb metapherein, meaning ‘to transfer.’ Simply stated, a metaphor serves to transfer the sense of one word to another. Many literary critics choose to explain metaphors in terms of the two words from and to which meaning is transferred: namely, the tenor and the vehicle. The tenor is the subject of comparison, what is to be compared, and the vehicle is the means of comparison, what the subject is compared to or with. A poem by Emily Dickinson offers a useful example:
‘Hope’ is the thing with feathers –
That perches in the soul –
And sings the tune without the words-
And never stops – at all –
And sweetest – in the gale – is heard –
And sore must be the storm –
That could abash the little Bird
That kept so many warm – [-p.100]
I’ve heard it in the chillest land –
And on the strangest Sea –
Yet, never, in Extremity,
It asked a crumb – of Me.
In the first line of the poem, the metaphor is implicit: the tenor is clearly identified as ‘Hope,’ but the vehicle (bird) is described only as ‘the thing with feathers.’ In the second stanza, the metaphor becomes explicit with the naming of the vehicle (‘little Bird’). ‘Hope’ is the subject of comparison, and ‘little Bird’ is what the subject is compared to. According to Dickinson’s metaphor, hope is something like a bird in the sense that it ‘never stops’ comforting us, much as a bird seemingly ‘never stops’ singing. This comparison between hope and a bird is maintained and developed throughout the poem, making it an extended metaphor.” (emphasis in original, pp.99-100)
Barton and Hudson continue: “The following passage from T. S. Eliot’s ‘The Love Song of J. Alfred Prufrock’ (1917) offers another example of an extended metaphor:
The yellow frog that rubs its back upon the window-panes,
The yellow smoke that rubs its muzzle upon the window-panes,
Licked its tongue into the corners of the evening,
Lingered upon the pools that stand in drains,
Let fall upon its back the soot that falls from chimneys,
Slipped by the terrace, made a sudden leap,
And seeing that it was a soft October night,
Curled once about the house, and fell asleep.
Throughout these lines, the tenor is ‘fog’ or ‘smoke,’ and the vehicle is a cat. Thus, the fog ‘licked its tongue into the corners of the evening’ and ‘curled once about the house, and fell asleep’ in the way of a cat. This metaphor is related to personification.
Some poets delight in original and outlandish metaphors; John Donne’s ‘Holy Sonnet XIV’ (1633) offers several examples of unusual comparisons:
Batter my heart, three-personed God; for You
As yet but knock, breathe, shine, and seek to mend;
That I may rise and stand, o’erthrow me, and bend
Your force to break, blow, burn, and make me new.
Donne implicitly compares the Holy Trinity to a tinker (whose job it is to ‘knock, breathe, shine, and seek to mend’ metal objects) and a black-smith (whose profession calls for him ‘to break, blow, burn, and make… new’). Here the metaphors are also conceits.
Other poets employ obvious and conventional metaphors, which can be just as effective and poignant. In his poem entitled ‘The Fist’ (1976), the contemporary Caribbean poet Derek Walcott writes, [-p.101]
The fist clenched round my heart
loosens a little, and I gasp
brightness; but it tightens
again. When have I ever not loved
the pain of love? …
In this metaphor, the tenor ‘pain of love’ is compared to the vehicle ‘the fist clenched round my heart.'” (emphasis in original, pp.100-101)
Ref: Edwin Barton and Glenda Hudson (c1997) A Contemporary Guide to Literary Terms with Strategies for Writing Essays about literature. Houghton Mifflin Company: Boston and New York)
NOTE also: Myers and Wukasch
“metaphorical dissolve a device of transition, borrowed from film, in which separate actions or images are fused by means of their similar, implied meanings. For instance, a transition is often made between lovers in the throes of passion and an onrushing train. Poetry employs the device through JUXTAPOSITION between lines or the beginning and ends of stanzas.” (emphasis in original, p.220)
Ref: Jack Myers and Don Charles Wukasch Dictionary of Poetic Terms. University of North Texas Press: Denton, Texas, 2003