Whirling Hygrometer

Whirling hygrometers, also known as sling psychrometers, employ the ‘wet’ and ‘dry’ bulb principal to determine percentage Relative Humidity. A whirling hygrometer is a very accurate way of measuring the relative humidity of the air. This Brannan hygrometer is filled with spirit and has a fixed handle designed to be rotated by hand to provide adequate and consistent ventilation of the bulbs. Measurements in Celsius only.