Anemometers measure wind speed. Vane anemometers also measure wind direction. The image shows a vintage cup anemometer.
IMAGE: By photographer: Archival Photograph by Mr. Sean Linehan, NOS, NGS - The Aims and Methods of Meteorological Work by Cleveland Abbe, in Maryland Weather Service, Johns Hopkins Press, Baltimore, 1899. Volume I, page 316.NOAA's National Weather Service (NWS) Collection, Image ID: wea00920.Source link: http://www.photolib.noaa.gov/htmls/wea00920.htmDirect link to image: http://www.photolib.noaa.gov/bigs/wea00920.jpg, Public Domain, https://commons.wikimedia.org/w/index.php?curid=9682749