LIME AND CEMENT INDUSTRIES 837 



series is broken and worn down to the size of wheat kernels and 

 is exceedingly hard to reduce. The harder bnrned portions make 

 a cement which has a much higher tensile strength than the 

 normally burned product. 



The method of manufacture in use at the other works at Akron 

 is somewhat similar to that employed at the plants at other locali- 

 ties in the state, but the kilns are in part of a more modern type, 

 being made of sheet iron instead of stone, but, like the ethers, 

 they are lined with fire brick. 



The Union Akron cement co. is also contemplating the manu- 

 facture of Portland cement. 



Buffalo district 

 The Buffalo cement co. has quarries on Main street near the 

 belt line of the New York Central railroad (pi. 84). The cement 

 bed underlies the Onondaga limestone. The section in its quarry 

 shows : 



Feet 



Cherty limestone 7 



Massive limestone ..' 4 



Impure limestone called " bullhead " 6 



Cement rock 4 



The rock is burned in the ordinary stone kilns lined with fire 

 brick, there being 10 of them, set in two rows. The rock is 

 loaded on cars and hauled up an inclined plane to the top of the 

 kiln, into which it is charged together with the coke that is used 

 for fuel. 



Both the normally burned and the clinkered material are fed 

 into the grinding machinery. The first set of machines are 

 Steadman disintegrators, and from these the material is passed 

 over a screen, all that passes through representing the normally 

 burned cement rock. The clinkers which are not broken fine 

 enough by the disintegrators to pass through the screen are con- 

 veyed to a Griffin mill, where they are ground to make Portland 

 cement. The total capacity of the plant is about 750 barrels a 

 day. 



