Historic. Founded in 1754 as the city’s first public library, it served as the Library of Congress after the Revolution. Melville, Thoreau, and Auden all browsed the collection, which has topped 200,000 volumes. ($150 a year; 53 East 79th Street; 212-288-6900.)
This airy room has everything from basic manuals to the twelve-volume Luther Burbank: His Methods and Discoveries (1929), with Tiffany-designed cover and silk endpapers. Expert advice, plus a small shop for plant supplies, too. ($100 a year; 128 West 58th Street; 212-757-0915.)
At the 182-year-old Merc, you can relax in a leather club chair with any of 20,000 mysteries—like The Case of the Mysterious Moll (1945), by Harry Stephen Keeler—or 150,000 other works. Finish Proust, and they give you a prize. ($75 a year; 17 East 47th Street; 212-755-6710.)
In a midtown office building lie 40,000 Spanish-language works of fiction, poetry, and drama (and 1,000 English translations). The 2,500-title video library has Buñuel, Almodóvar, and silent-film pioneers like Segundo de Chomón. ($35 a year; 122 East 42nd Street, Suite 807; 212-661-6011.)
About 17,000 books on dogs, from De Canibus Britannicis (1570) to The Beagle: An Owner’s Survival Guide (2002). (Free; 260 Madison Avenue, near 39th Street, fourth floor; 212-696-8245.)