What is "panchakki"

Panchakki,( Devanagari: पानचक्की) also known as the water mill, takes its name from the mill which used to grind grain for the pilgrims. This monument located in Aurangabad, Maharashtra, displays the scientific thought process put in medieval Indian architecture. It was designed to generate energy via water brought down from a spring on a mountain. The building, attached to the dargah of Baba Shah Musafir a Sufi saint is located in a garden near the Mahmud Darvaza and consist of a mosque, a madrissa, a kacheri, a minister's house, a sarai and houses for zananas.