»Just mail the letter«, he said, »the stamp is on it.« She looked and saw the familiar carmine 8¢ airmail, with a jet flying by the Capitol dome. But at the top of the dome stood a tiny figure in deep black, with its arms outstretched. Oedipa wasn’t sure what exactly was supposed to be on top of the Capitol, but knew it wasn’t anything like that.
... She gave him goodbye, walked downstairs and then on, in the direction he’d told her. For an hour she prowled among the sunless, concrete underpinnings of the freeway, finding drunks, bums, pedestrians, pederasts, hookers, walking psychotic, no secret mailbox. But at last in the shadows she did come on a can with a swinging trapezoidal top, the kind you throw trash in: old and green, nearly four feet high. On the swinging part were hand-painted the initials W.A.S.T.E. She had to look closely to see the periods between the letters.
Oedipa settled back in the shadow of a column. She may have dozed off. She woke to see a kid dropping a bundle of letters into the can. She went over and dropped in the sailor’s letter to Fresno; she hid again and waited.