Under that all-weather title is a Mississippi River boy's rhapsody on a modern journalist's theme: the conjunction of economies, politics, and geography. Childs starts--as who doesn't?--with de Soto, the more practical and adaptable French, La Salle's descent of the river, the first woodsy settlements, the emigrant ""invasion"" (how they came, how they prospered), and a jolt: the outbreak of sectional hostility, South-and-West vs. North-and-East, over Jay's proposed surrender of navigation rights on the river to Spain in return for a commercial treaty advantageous to Atlantic ports. (Burr's rebellion fizzled; Jefferson wisely purchased the Louisiana Territory.) The keelboatmen, ""half horse and half alligator,"" gave way to steam--progress with panache: a young Roosevelt and his bride made ""a charming, Swiss-Family-Robinson expedition"" of the first perilous downriver trip. ""Every kind of pioneer boat"" joined the river traffic; ""floating towns"" formed at nightfall; New Orleans' exports rivaled New York's. Coming and going, ""young men acquired a taste for change, excitement, adventure in foreign parts. On the other hand, the river itself was a common bond. . . ."" And there were the steamboats, not only the region's pride, but ""a native form of transportation: a clause in the charter of western independence, of which the system of western rivers was the principal guarantee."" Childs pauses at ""the boy Samuel Clemens"" and ""the character of the raftmen""--before the destruction of the fiver world by Eastern-financed railroads and the inner weakness (chaos, cut-throat competition) of the fiver commerce. In Childs' boyhood, c. 1900, the Mississippi was ""a remote, lost river"" with ""no connotation of utility""--on its way to moonlight-and-magnolia sentimentalization. In 1934, ""I am bound down the fiver system""--twelve pig iron barges in tow--""that the government is remaking from north to south"": the product of sectional pressure, New Deal aspirations, and the US Corps of Engineers. As of 1978, he picks up the congressional fight (backed by the railroads) to make the user-corporations pay a user fee. These last sections, though interesting (and sometimes intensely evocative), are not integrated--and what happened to river commerce after the 1930s remains a blank. But Mississippi-minded readers whose interest was over-stretched, perhaps, by Jonathan Raban's moseying Old Glory will find Childs' eager, pungent portrayal a restorative.