PURPOSE: To enable accurate detection of direction and velocity of liquid with comparatively easy construction, by installing a heating element in the center and a measuring element on a branched path oriented to a plurality of directions from the center respectively.

CONSTITUTION: A heating element QH is heated periodically by a base current IB from the constant current source 21HB corresponding to a CLK from a circuit 22. A part of the heat is taken by the wind passing through the liquid path of a detecting element unit 2 and the heat is made to transfer to the path in the lower reach side. Velocity of this transfer of heat corresponds to wind velocity and direction of the wind blowing into the liquid path, changing a detected temperature of detecting elements QNWQW in the lower reach side located at a distance R from the heating element QH, and detecting signals TNWTW are obtained. There signals TNWTW drives transfer time signal shaping circuits 25NW25W for generation of the transfer time signals. As a result, a reciprocal number counter 33 E transmits wind velocity data uE to an arithmetic operation circuit 34 through a gate circuit 32E corresponding to for instance to an element QE on the lee ward side and the result of the operation is displayed on a wind velocity and direction indicator 35.