To simply provide a wind mill or a water turbine which is highly efficient in obtaining energy.

In the wind mill or the water turbine which is rotated in a horizontal direction, an individual blade can be revolved and gears are integrally fixed, the rotation of the gears of the blades is intercoupled through gears around an output shaft and usually fixed and intermediate gears, and gearing contact between the gears is effected in two spots to reduce a resistance loss. The number of gears is set such that the blade effects half rotation as against one revolution of an output shaft. All the blades are set to rotate in the same direction in a fixed position. The blade in a position crossing orthogonally with a flow of wind or water is crossed orthogonally with a flow of wind of the output shaft and the blade on the 180 degree opposite to the output shaft is positioned in parallel to a flow of wind and water. Further, against strong wind, the angle is shifted to lower rotation.