They were used to forecast the weather in the 19th century and now the ancient predictors are making a 21st century comeback for Christmas.

You might have seen them social media. Some say the storm glass can predict the weather.

But, do they really work? We bought one to test out.

First of all, it’s much smaller than it appears in pictures. The one we got is 2.36 x 4.72 inches.

The directions say to put the glass near a north facing window and to leave it for one to two weeks. We put it in our Sales Manager, Jeff Olsen’s, office.

"There's been a lot of interest. Everyone that's come in here said, what's that?” Olsen’s said.

The storm glass became popular in the 1800’s when it was promoted by scientist and ship captain, Robert FitzRoy, to predict the weather.

The sealed glass contains a mixture of chemicals. Changes in atmospheric conditions are supposed to produce a variety of shapes. After a little over a week, ours formed crystals in the bottom. According to the instructions, that means snow. At the time, it was snowing.

“But we can just look outside and see snow. Maybe that’s the route we should take. Yep, it’s going to snow”, says Olsen.

In the end, our take on the storm glass is that it's more of daily weather reporter. WZZM Meteorologist Laura Hartman says if you want a real forecast, it’s not going to come from the storm glass.

"Probably not, if you want more specifics, we might do a better job. But it's gimmicky, fun and might entertain your family and friends."

“It’s a conversation starter. Put it in your office. It's something to talk about", says Olsen.

You can search storm glass and find companies that ship in time for the holidays. They cost an average of $30. However, be mindful of delivery times. Some come from China and won't get here before Christmas.

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