A giant barometer, which is used to measure atmospheric pressure, is being built in the Engineering Building at Portland State University.

January Barometer refers to a belief that the S&P 500's performance in January can predict its performance for the rest of the year. The accuracy of the barometer has been mixed.

Knowing this, viewer Gordon Grizzle asked "How does a barometer work, and why is it important?" Thanks for your question Gordon! A barometer acts like a scale.