CLAYS OF NEW YOEK Y57 



Experiments made witli a sample of it sliowed that 28^ of water 

 was needed to work np the air-dried material, but in actual practice 

 the claj is so moist when it reaches the factory that little wafer has 

 to be mixed with it. The air shrinkage is 5^. At incipient fusion, 

 which occurs at cone .05, the total shrinkage is Ifo. Vitrification 

 occurs at cone 1 with lly^ shrinkage; this agreeing quite closely 

 with the amount that takes place in the manufacture of the brick. 

 At cone 3 the clay became viscous. 



The tensile strength of the air-dried briquettes ranges from 60 

 to YO pounds a square inch. The clay contains .55^ of soluble 

 salts. As the bricks are burned to vitrification these' do not produce 

 any harmful results. 



The bricks are molded either in a Penfield soft mud machine 

 or in a stiff mud plunger machine, in which case they are re- 

 pressed. The works are equipped with a large number of drying 

 tunnels, and both rectangular and circular kilns of the down-draft 

 type. 



Samples of the product tested from time to time show a high 

 crushing strength and very low absorption. 



Many of the streets in Syracuse are paved with brick from this 

 factory. They have also been used at other places. 



