This component anemometer consists of a Robinson's cup anemometer and a wind vane, as shown in the photograph. The arrangement for resolving the wind movements into longitudinal and latitudinal components is as follows.
The motion of the wind vane is transmitted to the grooved cylindrical cam by means of a hollow shaft. An uniform revolution of the cam causes a simple harmonic motion to a roller in the direction of its axis. The roller is in frictional contact with the surface of a disk, fixed upon an axis which intersects the axis of the roller at right angles. The disk is rotated by means of gearing down from the anemometer, namely proportional to the wind velocity V. Let one roller touch at the center of the disk when the vane turns in the East and West direction, and an other roller, in the North and South direction. Then the former revolves by, that is the integration of the longitudinal component, where θ is the angle of the vane measured from the North direction. Similary the latter revolves by, that is the latitudinal component.
Each revolution of these rollers causes a electrical contact and records N. S. E. or W. component to the recording or counting apparatus. Besides these there is a electrical contact set for recording the total wind range. Therefore these five elements of winds can be recorded electrically with six wires.
By this instrument we obtain not only great facilities for the climatological purpose, but also we can get the vector mean direction and velocity of winds which are difficult to measure on the level land up to this time. Moreover we can find the degree of “turbulence” of winds from the ratio of the vector mean velocity and the velocity from total wind range.
