CHAPTER XIV. 



FLOOR TILE, WALL TILE AND DRAIN 



TILE. 



CONTENTS. 



Floor tile. 



Raw materials. 



Method of manufacture. 



Character of product. 



New Jersey industry. 

 Wall tile. 

 Draintile. 



FLOOR TILE. 



This includes those forms of tile, of varying- colors and design, 

 which are used for floors and pavements. Two kinds are dis- 

 tinguished, viz., unicolored tile, in which the entire piece is of 

 uniform color, and encaustic tiles in which the colors of the 

 design extend inward from the surface to> a depth of about one- 

 eighth inch, the rest of the tile being usually buff. 



Ran' materials. — Great care is necessary in the selection of the 

 raw materials, for the clays used must be such that they will not 

 form surface cracks after being dry pressed. These cracks are 

 caused by the escape of the air compressed between the clay par- 

 ticles during the process of molding. The clay should also' be 

 free from any tendency to warp, or split in burning, and further- 

 more, the manufacturer must aim to adjust his mixtures, or 

 select his clays, so that the greatest number of colors can be 

 burned at one temperature. Clays used for floor tile should also 

 be as free from soluble salts, as is the case with those employed 

 for the manufacture of pressed brick or terra cotta, although, as 



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