CLAYS OF NEW YOKK 



655 



Hand power 

 Soft mud machiiies ■{ Horse power 



Steam power 



Moldine; -{ Stiff mud machines "i -oi ^ 



'^ ( l^lunger 



Dry press 



Semi-dry press 



^ Represses 



' Open yards, sun-dried 

 Covered yards, air-dried 

 Pallets 



Steam pipes circulating 

 witHn 



I 



Drying \ 



rr T ^ , T , , Hot blast 

 lunnels heated by i tt x • j* in 



•^ ±iot air irom coal nre 



through flues under- 

 j^ neath 



r 



Kilns i 



r Down-draft ] ^^^tangular i 

 I ( Uircular } 



Intermittent i I make 



ScO'Vekilns 

 Clamps 



Continuous -j ^*^^^f ^* 



One or more 

 chimneys ac- 

 cording t o 



I Up-draft ] 



Preparation of clay 



Few clays are found in nature in a condition such that they can 

 be fed directly to the molding machines; consequently they have 

 to be first loosened up. This breaking up of the clay mass can be 

 done by weathering, namely spreading the clay out in a thin 

 layer and exposing it to atmospheric action, the effect of this being 

 thoroughly to separate clay particles. This is a very thorough 

 method of preparation, but takes a long time and, if the clay con- 

 tains pyrite, the development of soluble sulfates is often brought 

 about. A quicker method of breaking up the clay is by means of 

 some form of machine such as the disintegrator, ball mill, or dry 



