CLAYS OF NEW YOKK 669 



Coarse-grained sandy clays permit rapid drying, wiiile very plas- 

 tic ones must be dried witli exceeding care. Fine-grained, sandy 

 clays may require slow drying, as the pores are so small that the 

 water can not escape rapidly, but it is not necessary to follow an in- 

 variable method in the burning. 



Bricks made by the soft mud process are usually dried in one 

 of three ways viz : 



1 Open yards 



2 Pallet yards 



3 Covered yards 



The first method is the most used, the second next and the third 

 least. In the first method the bricks are spread out on a hard 

 floor, in the open air. This floor, which is about 200 feet long, is 

 of brick, with a thin covering of sand, and is the " yard " proper. 

 At one end of it are the molding machines, at the other end the 

 kiln sheds. The yard usually drains toward one end, or from 

 the center toward both. After a day's production has been spread 

 out, the boy who tended the machine in the morning goes along 

 the rows and stamps them with a piece of board set on the end of 

 a long handle. This is termed " spatting ". After this the bricks 

 are turned on edge by another boy who goes along the rows with 

 a special tool, turning six bricks at a time. The next morning, if 

 the weather has been pleasant, the bricks are " hacked ", that is to 

 say they are piled on one another in a double row 11 to 15 courses 

 high along the sides of the yard and left till sufiiciently dry to put 

 in the kiln and burn. In case of rain the hacks are covered with 

 planking. 



The disadvantage of open yards is that the bricks are exposed 

 to the rain, and if a shower comes while they are spread out on 

 the yard, they become " washed ", getting a rough, uneven surface. 

 Washed brick are quite as strong as unwashed ones, but they bring 

 50 to Y5c less a thousand. The washed brick amount to about 15j^ 

 of the total production. ; 



