From the name, you might guess that a psychrometer is an instrument designed to measure your thoughts. Actually, it is an instrument that can help you forecast the weather. Read more to find out how it works.

A sling psychrometer is used to measure humidity levels. Read about its history, how it works, its design, and how to use it. Includes a relative humidity table.

Use this site to find out how humidity works and perform some activities related to humidity.

This site provides a discussion of dew point and relative humidity, containing formulas that look at connections between temperature, humidity, and dew point.

Information on what weather is to begin with, then progresses to how scientists can predict the weather. Common ways to predict weather are also included such as use of a barometer and rain gauge.

A look back in time at weather instruments used in previous centuries. Includes pictures and descriptions of instruments from Franklin Institute's historical collection.

Students are guided in how to build their own weather station that will measure temperature, humidity, precipitation, atmospheric pressure, and wind direction and speed.