Read it through once

But the mystery was explained when we got under way again; for these people were evidently bound for a large town which lay shut in behind a tow-head (i.e., new island) a couple of miles below this landing. I couldn't remember that town; I couldn't place it, couldn't call its name. So I lost part of my temper. I suspected that it might be St. Genevieve--and so it proved to be. Observe what this eccentric river had been about: it had built up this huge useless tow-head directly in front of this town, cut off its river communications, fenced it away completely, and made a 'country' town of it. It is a fine old place, too, and deserved a better fate. It was settled by the French, and is a relic of a time when one could travel from the mouths of the Mississippi to Quebec and be on French territory and under French rule all the way.