An Encyclopaedia of Indian Archaeology v1.c21.s12.3

v1.c21.s12.3

While pottery in a vertical up-draught kiln is baked hot gases rise up in the baking chamber and pass out through the chimney, inducing a natural draught of air. This draught is controlled to raise the temperature of the wood fire to 800° to 900° C in the baking chamber. But the heat within the chamber is not equally distributed. It is higher near the bottom and becomes progressively less towards the roof. Vertical down-draught kilns and horizontal kilns are better for a uniform distribution of heat within the baking chamber. In a vertical up-draught kiln the potter stacks the heavier thick-walled storage-jars at the bottom of the chamber and smaller thin-walled vessels higher up in the pile. Thus he sees to it that the heating is adequate for all the ware stacked in the kiln.