Leads.

Some people, I am told, have memories like computers, nothing to do but punch the button and wait for the print-out. Mine is more like a Japanese library of the old style, without a card file or an indexing system or any systematic shelf plan. Nobody knows where anything is except the old geezer in felt slippers who has been shuffling up and down those stacks for sixty-nine years. When you hand him a problem he doesn't come back with a cartful and dump it before you, a jackpot of instant retrieval. He finds one thing, which reminds him of another, which leads him off to the annex, which directs him to the east wing, which sends him back two tiers from where he started. Bit by bit he finds you what you want, but like his boss who seems to be under pressure to examine his life, he takes his time.

Wallace Stegner