IN the fall of 1965, I arrived in New York City, flush with somebody else’s oil money, to purchase books for a bookshop I was managing in Houston. The shop was called the Bookman and had several eccentric features: Our safe was the boll of a Louisiana gum tree; there was a room full of rare tobaccos, though smoking was forbidden; and there was even a young Asian man to serve sherry to such bewildered hicks as straggled in from time to time.

What we didn’t have were books, which was why I was in New York in autumn, walking up some dusty stairs to the famous Seven Gables Bookshop, managed then by Michael Papantonio and John S. Van E. Kohn, two of the most respected antiquarian booksellers of their time.

Back then, single-page printed ads bound inside the covers of books, promoting other books by the same publisher, were thought to establish the priority and value of that edition. But we at the Bookman discovered they had no connection whatsoever to value when, some years later, I stupidly sold these same gentlemen a beautiful copy of Thoreau’s “Walden” for a mere $12, because I thought the ads placed inside the covers mattered.

“Oh, we don’t pay attention to the ads,” Mr. Kohn said to me. Live and learn.

From the Seven Gables, I strolled down the street to the famous Gotham Book Mart, where a sign hung outside the store announced, “Wise Men Fish Here.” Frances Steloff, still the owner and in her 70s, was up on a ladder, pricing works on the occult; she never came down while I was present, and she soon sold the Gotham to a young Californian named Andreas Brown.