Antique Hygrometer c. Early 1900s

This is an antique hygrometer c. It is used for measuring the humidity of air. The closed glass system usually contains ether, which is condensed in the left-hand bulb, into which a thermometer dips.

Ether is then poured over the right-hand bulb, which is normally covered with a muslin bag. The cooling effect causes ether vapor in this bulb to condense and lower the vapor pressure inside the tube. The liquid ether in the left-hand bulb then starts to evaporate, and its temperature falls. At a certain point dew begins to form on this bulb, and the temperature of the ether is read; this is the dew point temperature for the surrounding atmosphere.

The dew-point temperature is a well-known function of the relative humidity of air. This particular model is similar to those of. Base diameter 4.25" (11.4 cm), height 9.5" (24.1 cm) and packaged weight approximately 0.45 kg. The item "Antique Hygrometer c. Early 1900s" is in sale since Wednesday, March 25, 2020. This item is in the category "Antiques\Science/Medicine\Scientific Instruments". The seller is "frommetoyou432" and is located in Armagh.

This item can be shipped to North, South, or Latin America, all countries in continental Asia, European Union member countries, Australia.

• Period: 1800 to 1900
• Type: Hygrometer

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