CLAYS OF NEW YOEK 645^ 



Most common "brick are made by the soft mud process, but 

 many are molded by the stiff mud process. In the burning of a 

 kiln full of such brick, some receive more heat than others, a 

 certain proportion become discolored, while the remainder may 

 be slightly misshapen by the weight of the overlying mass of 

 bricks. It is thus possible to sort the contents of any one kiln 

 into a number of different grades, the more important of which 

 are as follows: 



Salmon brick, soft brick. These are insufficiently burned brick, 

 which are not hard enough to be used in outside walls, but can 

 be used for backing or filling in. 



Arch brick are those from the arches of the kiln, or portions 

 nearest to the fires. These are consequently burned the hardest. 



Stock brick. These generally represent the best, from a kiln 

 of common brick. They are carefully sorted both as to color 

 and shape and consequently command a higher price. 



Sewer or cistern brick are the harder burned bricks of a common 

 kiln, which, owing to their impervious character as the result of 

 hard firing, are well adapted for damp situations. 



Washed brick. At those yards where the drying is done by the 

 open air, the surface of the bricks sometimes becomes roughened 

 by the beating action of rain. Such bricks when burned are just 

 as strong as unwashed ones, but they have usually been discarded, 

 excepting during certain intervals when they happened to catch 

 the fancy of some architects. 



Pressed brick. The name of these is due to the fact that the 

 green brick is sometimes subjected to pressure after molding, to 

 impart a smooth surface and sharp edges to it. 



Under this term are also included products of a variety of shades 

 and colors and of variable form. 



The plain colors include white, buff, yellow, gray, brown and 

 red, as well as numerous intermediate shades. 



