Saying one thing through another, with no word of comparison: instead of saying that something is like another thing, one says that it is. The image transfers to the subject the qualities of the thing it has been identified with.
In Dom Casmurro
My evident purpose was to tie the two ends of life together, and to restore adolescence in old age.
The "two ends of life" make existence a thread that could be tied, and the image weighs because it states the old man's wish to close life into a circle, joining lost adolescence to the present old age.
Chapters I to XII: The Accusation, the Opera, and the Promise, the narrator
Life is an opera, and a grand opera. The tenor and the baritone fight over the soprano, in the presence of the bass and the supporting cast [...]
Eyes of undertow? Well, undertow. That's the idea I get of that new expression. They carried some mysterious, forceful fluid, a force that pulled inward, like the wave that recedes from the beach on days of undertow.
Chapters XXIII to XXXIV: The Gypsy Eyes and the Eyes of Undertow, the narrator
Escobar kept rising thus from the grave, from the seminary, and from Flamengo to sit with me at the table, to greet me on the stairs, to kiss me in the study in the morning, or to ask me at night for the customary blessing
Chapters CXXV to CXXXV: The Resemblance and Othello, the narrator
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