CLAYS OF NEW YOKE 659 



age of tlie brick. Coal dust is also added by some manufacturers; 

 the advantage derived by its use will be mentioned under the bead 

 of burning. 



When soak pits are used, two men dig the clay in the afternoon 

 at the bank, while a third man levels off the material as it is dumped 

 into the pit and also adds the requisite amount of water. He is 

 called the temperer. In the morning the two diggers of the previous 

 afternoon shovel the clay from the soak pit into the machine. 



In many large brickyards separate gangs of men do the pit 

 shoveling and digging of the clay. 



Ring pits. These temper the clay more thoroughly than soak 

 pits, but are not so extensively used, possibly because it costs a 

 trifle more to operate them. A ring pit, as its name implies, is cir- 

 cular, 25 to 30 feet in diameter, 3 feet deep and lined with boards 

 or brick. In this there revolves an iron wheel, 6 feet in diameter 

 and so geared that it travels from the center to the circumference 

 of the pit and then toward the center again. In this manner the 

 clay is thoroughly broken up and mixed with the sand and coal 

 dust, if the latter be added. The pitful is tempered in about six 

 hours; a pit holds sufficient for about 30,000 brick. The temper- 

 ing is usually done in the afternoon so as to have the material 

 ready for the next morning. When the tempering is finished, a 

 board is attached by ropes to the wheel and dragged round the pit 

 a few times to smooth the surface of the clay; a thin crust forms 

 on the surface and prevents the moisture in the underlying material 

 from evaporating. 



The working of ring pits is similar to that of soak pits, the only 

 difference being that the temperer previously mentioned is gen- 

 erally employed in the morning to wheel the clay from the ring pit 

 to the molding machine. 



As a rule there are two ring pits to a machine, so that while the 

 clay is being shoveled from one pit to the machine, the other pit is 

 tempering clay for the next day, or two pits and two machines are 



