The Jai Prakash is a bowl shaped instrument, built partly above and partly below ground level, as can be seen in the drawing below. The diameter at the rim of the bowl is 17.5 feet for the Jaipur instrument, and 27 feet at Delhi. The interior surface is divided into segments, and recessed steps between the segments provide access for the observers. A taut cross-wire, suspended at the level of the rim, holds a metal plate with circular opening directly over the center of the bowl. This plate serves as a sighting device for night observations, and casts an easily identifiable shadow on the interior surface of the bowl for solar observation. The surfaces of the Jai Prakash are engraved with markings corresponding to an inverted view of both the azimuth-altitude, or horizon, and equatorial coordinate systems used to describe the position of celestial objects.