[Gk. anemos, wind ; and metron, a measure.] A wind-measurer, to show both the pressure and the velocity of the wind. A pressure anemometer measures the force of the wind on a plate one foot square attached to one end of a spiral spring placed horizontally. The plate, by the action of the wind, is pressed against the spring, which yields, and by a pencil traces a curve on a strip of paper placed below it. Another pencil connected with the vane records the changes in the direction of the wind. Thervelocity of the wind is indicated by the revolution of wheels, the number of whose turns is recorded automatically.