The dew-point is determined by means of an instrument called a hygrometer.
In the instrument-screen we had a thermograph, hygrometer, and thermometers.
On the contrary, if the hygrometer shows continuing or increasing dryness, a stronger wind is probable, without rain.
Thus the hygrometer is worthy to be studied on a hunting morning.
The form of hygrometer most commonly met with at meteorological stations is called a psychrometer.
At length it grew to such a pitch, that the tube of the hygrometer containing the water was exhausted in a couple of nights.
It crawls forward in all weathers, like Richard Edgeworth's hygrometer.
Again, if hygrometer read 90°, the mean humidity corresponding is 59°.
It was of an hygrometer which, like the common ones, was to give the actual moisture of the air.
The humidity of the air was observed both by August's psychrometer and Saussure's hygrometer.
Any of several instruments that measure humidity. The most common type of hygrometer consists of two, side-by-side mercury or electronic thermometers, one of which has a dry bulb, and one of which has a bulb wrapped with a wet cotton or linen wick. As water evaporates from the wet bulb, it absorbs heat from the thermometer, driving down its temperature reading. The difference in temperature between the two thermometers is then used to calculate the relative humidity. This type of hygrometer is also called a psychrometer. Other hygrometers make use of the temperatures at which dew forms and disappears to calculate the relative humidity. Older hygrometers used the length of a strand of hair, which stretches when it absorbs moisture, to measure relative humidity.