The barometer has the ability to recreate the effect of the Philadelphia Experiment; that is to freeze time over a limited area for 47 seconds. The activator and whoever else is touching the barometer is able to move through the freeze.
The Philadelphia experiment was an attempt to make US Naval ships invisible to the enemy by using high power magnets. It kind of worked - the ship did disappear from radar for 47 seconds.
At first, Artie thought this artifact was a Napoleon Bonaparte artifact because his kiss with Josephine lasted exactly 47 seconds.
- Owned by Jim, previously a member of Myka's Secret Service team in Denver. It turns out that he used the barometer to make Myka late so his partner Leo would be able to finish Sam off. He lent the barometer to Leo so he would be able to get away and later used the barometer to double-cross Leo, setting him up to take the fall. When Myka found out it was Jim who orchestrated the deaths of Sam and Leo, she stopped him from using the barometer to get Pete killed.
- Artie stole the artifact from the Warehouse and first used it when he was arrested by customs at Liszt International Airport to escape. He later used it when Myka threw the dagger into the grinding wheel and he had to run to save the dagger before it was destroyed.