The white structure, which resembles religious architecture, is a kiln for making quicklime. The lime is put into the kiln, where it burns over coal at a high temperature of 1,000 degrees. Raw lime is transformed through a chemical reaction into a substance from which cement is made. The burning lasts three days and three nights, during which time the workers take turns adding coal. These men were working silently exposed to the relentless pressure of high-temperature smoke from the burning coal. (Madhya Pradesh, India 2015)