WIFITESIDE COUNTY. 143 



north many miles. Xear the north-east comer of Garden Plain, the low 

 aliuvial bottom strikes oft' towards the south-east; leaves the Mississip- 

 pi river altogether; makes a junction with the alluvial bottom of Rock 

 creek in the township of Trenton ; and thence extends itself to the allu- 

 vial bottom of Rock river near the village of Erie. It contracts to an 

 average width of half a mile. Low, abrupt, oak covered hills rise from 

 its edges. This is the Cat-tail slough, so famous for its magnificent de- 

 posit of peat, of which more will be said in another part of this 

 report. 



Three distinct river beds are easily recognized at the present time. 

 First, there is its present bed, about one mile wide on an average; sec- 

 ond, the low wet alluvial above referred to, and now subject to periodic 

 overflows. When the waters filled this, the river averaged two or three 

 miles in width. Lastly, the river once flowed a broad stream from bluif 

 to bluff, and averaged six or seven miles in width. Then a heavy body 

 of water flowed lazily through the Cat-tail, but as the great stream went 

 down, this branch of it ceased to flow, and in its water-soaked bed 

 gradually grew a great thickness of the best peat. 



The Marais d'Ogee or Maredosia slough, as it is usually called, or 

 Dosia, as it is called in the common speech of the people, is another 

 broad marsh, spreading out along the line between this and Rock Island 

 comity, and extending in a nearly north and south direction, connecting 

 Hock river with the Mississippi. Cat-tail slough is similar to the Maredo- 

 sia. runs nearly parallel to it, and is distant some five or six miles from it. 

 When the Mississippi river is high, the water runs south through these 

 sloughs into Rock river; when Rock river is high, the water runs the 

 other way. The highest point between low water mark in the two riv- 

 ers along the Maredosia is thirteen feet ; along the Cat-tail, it is twenty- 

 six. These figures are obtained from actual surveys made along the 

 sloughs in winter. I am indebted to the courtesy of Mr. J. ABBOTT, an 

 accomplished engineer and surveyor of Cordova, for this interesting 

 information. 



There can be but little doubt that the Mississippi river itself once 

 flowed through the Marais d'Ogee. The evidence seems conclusive to 

 any one making an examination of these localities. The broad bottom, 

 several miles in width, looks like the Mississippi bottom. Then the 

 mouth of Rock river was a mile or two below Erie. The same broad 

 bottom runs along Rock river from Erie to Rock Island. Round this 

 channel the distance to Rock Island is twenty miles greater than along 

 the present course of the river. ' If flowing round this way at the pres- 

 ent time, this increased distance would give the usual fall of six inches 

 to the mile; but along the present channel of the river from Albany to 

 Rock Island the distance is twenty miles less, and the fall eighteen 



