When William Sydney Porter had his first book, Cabbages and Kings (1904), published he had only six more years to live. But, with his identity hidden beneath the legendary pen name O. Henry, the fame of his short stories was already firmly established in New York. By then he had written and had published in several magazines at least half of the nearly 300 stories that would fill eight more volumes before he died--and still another seven published within the two decades after his death. These sixteen collections of stories, however, were only a prelude to the avalanche of later editions, authorized and pirated, that would bring his works, in English and translated into dozens of foreign languages, to readers throughout the world as well as in the United States and other English-speaking countries. Since this process of dissemination is still going on, there is no way of estimating how...