The Jander or Jandar (as it is called by the locals in Murree, Pakistan) is a water driven mill that was commonly used in the mountain areas of the Murree Hills where water is abundant. Janders were very common during the barter economy era but have been replaced by diesel and electric mills which are more efficient and are able to operate all year, as they are not dependent on seasonal rains. They are also more accessible than janders, which had to be located on the banks of running streams, generally some distance away from where people lived. Some janders are still operating in the foothills. The local tribes of the Murree Hills such as the Dhanyal, Abbasi and Satti were the main users of these traditional mills.
A Jander consists of three main parts:
1. The fan (operated by water flowing from an elevated point).
2. Millstones (two large wheel-like structures that rotate on an axle and can weigh up to a ton. They are rotated by the fans).
3. The cone (used to funnel grain between the millstones for grinding).
A jander operates as follows:
Water is stored at a small, elevated, dam-like collection point. Typically, the water is diverted from a large stream or mill pond to the water wheel along a channel or pipe (also known as a flume or head race). The potential energy of the water's movement drives the blades of a wheel and converts it to mechanical energy, which in turn rotates an axle that drives the jander's mill stones. Water leaving the wheel is drained through a tail race. The passage of water is controlled by gates that allow some measure of flood control.
There are two types of janders: one with a horizontal water wheel on a vertical axle, and the other with a vertical wheel on a horizontal axle. The horizontal janders are the older design. The force of the water would strike a simple paddle wheel set horizontally in line with the water. This then turned a runner stone balanced on the rynd atop a shaft leading directly up from the wheel. The bed stone does not turn. The problem with this type of mill was the lack of gearing. The speed of the water set the maximum speed of the runner stone which, in turn, set the rate of milling.