The most surprising mongo hunter is Iver Iversen, an expert in historical restoration who spends a good portion of his free time climbing into dumpsters parked outside Upper East Side town houses under renovation. One of his greatest finds was a frosted-glass pantry door on the curb in front of Jacqueline Onassis's apartment shortly after her death.

After moving to New York in the 1990s and furnishing his apartment with bounty from the city streets, the author discovered he wasn't the first or only enterprising scavenger around. In this entertaining narrative, Botha (Apartheid in My Rucksack) delves into a world of avid collectors who forage New York's garbage for everything from empty soda cans and leftover sushi to old coins and first editions. These treasures even have a distinct name — mongo — … Botha explains. Each chapter examines a different category of mongo seeker, from pack rats and preservationists to voyeurs and visionaries, whom Botha befriends and accompanies on their mostly nocturnal routes.

Other exhibits at the gallery were a 1,500-square-foot transparent map showing the locations of Sanitation Department offices; three piles of televisions on which videotapes of sanitation workers were shown, and an old, department-section office furnished in ''mongo,'' discarded furniture salvaged by sanitation men.