In the winter of 1843–44 the American Fur Company built a new boat, the _Nimrod_, designed to correct certain defects in the _Omega_, and in this boat the voyage of 1844 was made. As in the previous year, Captains Sire and La Barge were master and pilot. It was in the spring and summer of this year that occurred the great flood of 1844. This appears to have been the greatest flood in the lower Missouri and central Mississippi ever known before or since. The entire bottoms in the vicinity of St. Louis were covered with water to a width of several miles. The flood had the curious effect of completely filling up the old bed of the river, so that, when it subsided, the river had to cut out a new channel, and it was many years before the channel was restored to its condition before the flood. The high water lasted far into the summer. When Captain La Barge returned from his trip to Fort Union he ran his boat up Washington Avenue to Commercial Alley, where he made her fast through a window in J. E. Walsh’s warehouse at the corner of those streets. This great flood was mostly from the lower country, and scarcely at all from the mountains. When the _Nimrod_ reached the Omaha villages, a short distance below the modern site of Sioux City, Ia., she found the water so low that she was compelled to wait several days for a rise. This fact is a noteworthy one, as another refutation of the popular idea that floods in the Mississippi have their origin in the melting snows of the Rocky Mountains. As a matter of fact they always come from the heavy rains of the lower country.