This Windmesser or Anemometer Air-speed Indicator or ASI was manufactured by Wilhelm Morell in Leipzig with a scale of 0-25 which corresponds to a maximum airspeed of 250 KPH or 155 MPH.  This particular example has a serial number of 124096.  The cups spin and the apparatus appears to be in working order. This windmesser comes with its box but not with the stand shown below as that belongs to another windmesser.