Old and new fans of the great Barnum now have at their call: the proliferous autobiography, pulled into shape by George S. Bryan (1927); Neil Harris' searching life-and-works, Humbug (1973); and, for the first time ever, a selection of the surviving letters. ""Astor gave the public a library; Cooper gave them an institute. . . . Why should not Barnum (who in fact has always been more of a philanthropist than a humbug) establish a free museum for the instruction and edification of the Youth of America!"" But, alongside--""I propose to erect Barnum's American Museum with its giants, dwarfs, fat women, bearded ladies, baby shows, dog shows, wax figures. . . ,"" admission 25 or 30 cents. As circus-historian Saxon notes, there are no revelations: Barnum was not given to ""introspection or self-doubt""; the juiciest of the letters--including the foregoing and the roguish exchanges with fellow ""museum man"" Moses Kimball--are quoted in the Harris biography. But there is nonetheless much delight and illumination here. The two Barnums, the social reformer and the showman (or the altruist and the opportunist), appear repeatedly as one. Converted to teetotalism, Barnum produces The Drunkard, a box-office hit ""universally conceded to be one of the most powerful auxiliaries the temperance cause has ever received in this country""; lecturing lucratively on ""Success, or the Art of Money-Getting,"" he promises that his lecture, ""although brimful of lively mirthful anecdotes, is. . . well calculated to do good and especially to the young. . . ."" To Henry Ward Beecher, accused of adultery, he offers $10,000 for ten platform appearances; to bankrupt Ulysses S. Grant, ""one hundred thousand dollars cash, besides a proportion of the profits,"" for a chance to exhibit his trophies. Are these soundings different from his worldwide search for ""savages"" or freaks, his lifelong quest for topical exotica--Queen Victoria's robe or 100 famous-men's hats? Barnum, it appears, genuinely equated entertainment and edification, and had a natural genius for identifying his interests with others'. As advertising's greatest champion, he expects favorable newspaper notices. Still: ""I never believed that any amount of advertising or energy would make a spurious article permanently successful."" There is more on the celebrated attractions--from Joice Heth to Jenny Lind to Jumbo; on Barnum's relations with his business associates--including the circus monopoly he engineered (a remarkably explicit letter) shortly before his death; and on his family relations--not, apparently, blissful. With an informative introduction, a handy chronology, thoughtful headnotes, and a note on sources: accessible to the merely curious and ready-made for scholars.