People started waiting at the Union Square Barnes & Noble at 1:30 p.m. on Monday, five hours before former President Jimmy Carter was scheduled to begin signing his latest book. By 5, the event was filled to capacity. In the line that snaked through the fourth floor was a couple who had dressed their toddler in a T-shirt that declared, “I’m nuts about Jimmy Carter,” and a man who had bought 50 copies of Mr. Carter’s “Beyond the White House: Waging Peace, Fighting Disease and Building Hope” (Simon & Schuster), to be autographed and saved for Christmas presents.

Not Harry Potter, but not bad.

Once he arrived, Mr. Carter, 83, cheerfully whipped through the books — 1,600 in about 90 minutes — with the machinelike efficiency of a subject in a time-and-motion study. A book tour, he said, is “like being on the campaign trail.” There are back-to-back interviews, frequent airplane flights, long lines of eager people to meet. And at the end of the day, whether from too many handshakes or too many signatures, you’ve got a sore hand.