290 



fifty feet above the present bottoms. They are never covered by overflow 

 from the river at the present time. 



The whole region about Lafayette is deeply buried under glacial de- 

 posits, the depth of these deposits being usually very great (at least 150 

 feet), though in limited areas they may be quite tbin or lacking. Only 

 rarely, however, do the underlying Palaeozoic limestones reach the surface. 

 One such outcrop I have seen on the upland near Montmorenci where 

 the Lake Erie and Western Railroad crosses Indian Creek. Outside of 

 these rare and insignificant cases, the whole country is underlaid by a 

 very coarse glacial gravel. Overlying this is usually a layer of loess 

 varying in thickness from an inch to several feet. From this loess are 

 derived the representative soil types of the region. 



The drainage of the region is in general good. The streams are few 

 and in periods of protracted drought frequently dry up entirely in their 

 upper courses. Most of the rainfall, however, is carried off by under- 

 ground drainage, the underlying gravel allowing the ready percolation of 

 water. Locally, as in upland swales and depressions and at the base of 

 the river bluffs, where the seepage of underground water takes place, the 

 ground is, except in seasons of drought, more or less completely saturated 

 with water resulting in the formation of swamps. At the present time 

 most of these naturally wet areas, especially on the upland, have been 

 artificially drained and the land utilized for growing crops. The bottom 

 lands are at present well drained, the cultivation of the soil breaking it 

 up into a loose condition which allows the water to flow off readily beneath 

 the surface. 



On the upland the dominant soil is a fine-grained, silty loam, varying 

 in color from light brown to almost black, the color depending upon the 

 amount of organic matter present, which is usually considerable. Of this 

 soil the Bueau of Soils recognizes two categories which are termed re- 

 specively Marshall silt loam and Miami silt loam. Both are nearly 

 alike in mineral content, being characterized by relatively high per cent- 

 age of silt and clay and extremely low per centage of sandy constituents, 

 but differ in their organic content, the Miami being as a rule much 

 poorer in this respect than the Marshall. The table shows the mechanical 

 composition of the soils, the data being taken from the Bureau of Soils 

 report. 



