210 GEOLOGY OF ILLINOIS. 



masonry. On first being quarried it is too soft and crumbling ; but ex- 

 posure to the weather seasons it and adapts it to the above purposes. 

 It is not a good building stone, but for want of a better is used to some 

 extent. It is very coarse-grained and gritty. 



The thin band of outcropping limestone above referred to furnishes 

 a hard, compact building stone, rather unshapely and hard to work as 

 it comes from the quarry. The quality is good and the color is warm 

 and rich ; but the trouble of working it into shape will always prevent 

 its use, except for rough masonry. Good stone can be obtained so easily 

 from La Salle and Joliet, that it will not pay to quarry these limestones 

 extensively for building purposes. 



Over the upland prairies, and even along the eastern bluff range, 

 stone quarries and outcrops of stone are hardly to be met with. The 

 farm houses and barns are built upon blocks, bricks, and all sorts of 

 foundation materials, except good foundation stones. In riding through 

 a country, and observing the foundations of the houses and barns, an 

 unfailing indication may be had as to the condition of the country with 

 reference to the outcrop of rocky geological formations. Applying this 

 test to eastern and western Marshall county, we shall not be disap- 

 pointed. A few of the hills show a gravelly appearance, or limited out- 

 crops of abard t ringing, light colored rock, and that is about the extent 

 of the outcrops which i>resent themselves for examination. 



Lime. A few lime kilns now are or have been in operation in the 

 county. One of these, about one mile above Sparland, on the point of 

 a bluff, makes a considerable quantity of very good lime. The material 

 used is the light-colored, hard limestone from the thin outcrop near the 

 top of the bluff. The lime is very white and rather fine-grained. It is 

 used in the neighborhood quite extensively, but will never, perhaps, 

 become an article of shipment to other counties. All points accessible 

 to railroad depots can be supplied with good lime from other localities 

 so easily and cheaply that these lime kilns will never obtain anything 

 but a local trade. 



tiands and Clays. All along the' Illinois river plenty of good river 

 sand may be obtained fit for various economical purposes. It lies in 

 banks and drift beds, and ranges from a fine washed to a coarse gritty 

 grain, according to the conditions of the waters which assorted, ar- 

 ranged and deposited it. Its color also varies. In some places it is 

 almost as white as St. Peter's sandstone. In others it is of a yellowish 

 and brownish hue. 



The clays of the Illinois river -bottom are especially suitable for the 

 manufacture of common red brick. They are partially mixed with 

 sand, and burn into a very solid, ringing brick, well adapted for ordi- 

 nary building purposes. 



