A penniless Jewish emigrant from Nazi Germany finds wealth and happiness in the US. Founder of the Bettmann Archive, perhaps the world's best-known pictorial library, Bettmann knows where his bread is buttered. To illustrate this breezy autobiography, which runs from his birth in 1903 Leipzig to his recent appointment as curator of rare books at Florida Atlantic University, the author picked copious choice examples from his gigantic collection. With the trademark Bettmann penchant for the unusual, the pictures depict everything from Bach's skull to a toenail-cutting machine, and sometimes bear only a distant relation to the text. No matter: Every one is a gem. The prose suffers by comparison, although Bettmann does catch the fairy-tale atmosphere of N.Y.C. immigrant life in the Depression, and has some fascinating memories of the land he left behind (attending a university course taught by Edmund Husserl: ``an absent-minded, goateed Jewish man entered the class, affixed his pince-nez, and began reading in an almost inaudible voice from a prepared text''). Similar little anecdotes enliven Bettmann's tale of how he escaped the Nazis (``some kind of nut,'' one goon muttered when Bettmann crossed the border with his collection stashed in two trunks); married ``a genuine, vital American woman''; and founded the Archive through luck and, as he admits, workaholism. Famous people do walk-throughs (Edward Steichen; Barbara Tuchman; Alfred Kinsey, who buys a hot painting from Bettmann for his Institute for Sex Research). Bettmann describes the pix he never found (a portrait of Daniel Fahrenheit, inventor of the thermometer scale; a painting of Spinoza grinding lenses) and some of his peculiar assignments (cable from Mott: ``Send everything you've got on apples''). Meanwhile, the eye keeps returning to those fabulous pictures (221 b&w).