Psychrometer

Instrument used to measure atmospheric humidity. It consists of two thermometers (wet-bulb and a dry-bulb) one of which has its bulb covered by a moistened wick. Humidity is determined by the difference in readings between the two thermometers after air has passed over both of them for a specific time period.

Geography teacher at heart and author of http://sageography.myschoolstuff.co.za. Account Manager for http://www.campuspress.com. Passionate about South Africa!