Geography of Ohio 155 



enabling the car wheels to hold. Engines and street cars are 

 generally equipped with sand bins, and the sand is sometimes 

 used also on level stretches wiien the tracks are wet. According 

 to Mineral Resources for 1908, Ohio ranked fourth in the pro- 

 duction of engine sand. 



Furnace sand. The demand for this is connected chiefly with 

 the brick making industry; the sand is used between the bricks as 

 they are placed in the kiln. This film of sand, which does not fuse 

 under the temperature for burning brick, keeps the bricks from 

 baking together. In still other industries, there is a demand for 

 furnace sand. In the production of this sand, Ohio leads all the 

 states. 



LIME 



According to the government reports for the year 1908, only 

 Pennsylvania produced more lime than Ohio. Ohio contains a 

 wide belt of limestone outcrops. These involve rocks ranging from 

 quite pure calcium carbonates to a dolomitic amount of mag- 

 nesium. 



Formerly local kilns w^ere operated at many points in the state. 

 Now this industry is confined to certain centers, among which 

 are Kelly's Island, Marblehead, Sandusky, Springfield, Cincin- 

 nati, and Marble Cliff near Columbus. This centralization is the 

 result of modern business methods. Competition has led to the 

 invention of machinery, which makes a great difference between 

 the modern lime plant and plants of a generation ago. Not only 

 the sources of raw material, but the shipping facilities for the 

 finished product, are factors in the location of a lime plant. 



The hydrated lime is to-day usually marketed as an impalpable 

 white powder. This is the ordinary lump lime slaked, and pow- 

 dered by grinding. 



Uses. The various building trades require great quantities 

 of lime, mostly as a mortar or wall finish. Several chemical 

 industries also require lime. Much is used in the manufacture of 

 glass, flint and plate glass particularly. Farmers have learned the 

 value of lime on acid and clayey soils. Tanneries, paper mills, 

 and sugar factories consume quite an amount of lime, as do also 

 the manfacturers of basic steel, and of refractory brick. It enters 

 also into the manufacture of soap and glycerine ; its use as a dis- 

 infectant is increasing. 



