vesimylly

A vesimylly, or water mill, is a mill powered by a water wheel that converts the energy of flowing or falling water into mechanical work, most commonly for grinding grain into flour. It is a traditional rural technology found in many parts of Europe, including Finland, and has also been used for other tasks such as sawing timber and fulling cloth.

The basic operation involves diverting some water from a river or stream into a mill race or flume to accelerate and guide it to the wheel. The wheel’s rotation drives a shaft connected to gears and, in most cases, to one or more millstones. Grain is fed from a hopper into the space between the stones, and meal emerges from between the rotating bedstone and runner stone. Proper water management through tailraces and sluices controls the power and speed of the mill.

Historically, vesimylly were widespread in rural landscapes from the Middle Ages into the 19th century. They were often built along rivers or streams with sufficient head and flow and were among the first automated sources of mechanical power before the advent of steam and electricity. Different wheel types—undershot, breastshot, and overshot—reflect local water conditions and head available.

Today, many vesimylly survive as preserved historic sites, museums, or functioning demonstrations. They illustrate traditional hydropower, agricultural processing, and regional architectural heritage, and they remain symbols of rural ingenuity and early industrial technology.