Ixiv FISHES OF ILLINOIS 



the channel formerly constituted the sole line of discharge for the 

 Ohio or not. Possibly the river divided its waters between the 

 Cache and its present channel. The bluffs of the powerful stream 

 which excavated the valley of the Ohio extend from the Mississippi 

 half-way across Alexander county, and then turn northeast, leaving 

 a bottom from 3 to 5 miles in width between them and the Cache. 

 The headwaters of Cache River are in eastern Union county, the 

 river winding first southeast, then south-southwest, south, and east, 

 emptying finally into the Ohio River a few miles below Mound City. 

 It traverses a distance of about 70 miles, beginning at an altitude of 

 500 feet. It falls 50 feet in a little over 2 miles, 100 feet in the next 

 15 miles, and only 70 feet in the remainder of its course. Near its 

 head it has a definite channel, but just west of the Union-Johnson 

 county line it enters its first cypress swamp. This, however, is 

 very small, and the bottom-lands again become higher and drier, 

 averaging about half a mile in width for the next nine miles. Then 

 for a distance of about 3 miles there is scarcely any bottom-land, 

 below which the river enters an extensive cypress swamp having 

 a width of 5 miles in some places. A few miles above CoUinsburg 

 the bottom again becomes narrow and ledges of sandstone form the 

 bed of the stream, which here is clear and swift. Below this point 

 the water is nearly stagnant, brown in color, and full of drifted logs. 

 The lowlands average about three fourths of a mile in width to near 

 the mouth of Dutchman creek, where they spread out to almost two 

 miles. At the Massac countv line, Cache River enters the main 

 swamp region which extends across Pulaski county, and below 

 these swamps the river winds about through wide bottoms to its 

 mouth. The backwater of the Ohio reaches up Cache River hardly 

 as far as Ullin, and floods above this point are more immediately 

 caused by the headwaters of the stream when their discharge is 

 impeded by backwater. The country around the upper Cache is 

 hilly and precipitous, and so in times of freshets it pours immense 

 quantities of water into this lower flat, which then becomes a reser- 

 voir. As the waters which the Cache carries come from rocks of 

 subcarboniferous and cretaceous ages, they are somewhat different 

 in mineral characteristics from any of the rivers heretofore de- 

 scribed. 



Big Bay Creek 



Big Bay creek drains eastern Johnson and western Pope counties 

 — an area very similar in character to that drained by the Cache. 

 The stream rises in northwestern Pope county, flows southwest into 

 Johnson county, takes there a southeasterly direction, and empties 



