A description is given of two recorders and an anemometer for measuring gusts, which were developed for use in a survey of the available wind-power in Great Britain. The essential feature of the recorders is that they operate unattended for a period of one week. The first instrument is a photographic recorder which shows, at intervals of half an hour, the wind direction and the run of wind past four standard cup contact anemometers. The second instrument records a mark for each two miles of wind, and will make up to four simultaneous records. The anemometer for measuring gusts uses a perforated aluminium sphere as the detecting element and a mechanoelectronic transducer valve to convert the mechanical response to an electrical output. It is compensated for changes of temperature and for the static effects of atmospheric pressure. When used with an amplifier-driven recording voltmeter, the response of the prototype instrument to an instantaneous change of wind speed from 65 to 85 m.p.h., was completed in about 0.07 sec. Modified forms of the instrument are described which measure, respectively, the horizontal components of the wind in two directions at right angles and the vertical component.