This is Roald Tweet on Rock Island. Some of the finest schools on the Upper Mississippi River in the 19 th century were the ten-acre rafts of Minnesota and Wisconsin white pine floating down to the sawmills of Rock Island, Davenport, and Moline. The twenty to thirty men who worked on these rafts and steered them down to the mills may not have diagrammed sentences or practiced their multiplication tables along the way, but they learned the habit of attention, and a philosophy of life likely more true than yours or mine.