Karl Schwarzchild's Pocket Watch

Origin
Karl Schwarzchild was a German physicist and astronomer who first provided the exact solution to Einstein's field equations of general relativity. This details the effects of gravity on a spherical non-charged space. A theory for the existance of gravity wells is named the Schwarzchild metric in his honor.

This artifact was used by Parcelcus as part of his time-travel mechanism in the season 5 episode "Endless Terror", and before that it (non-canonically) caused the events of the Eureka episode "Welcome Back, Carter" when it was implemented in an anti-gravity device. It was brought to the Warehouse by Douglas Fargo during his maintenance visit.

Effects
When properly used, the watch can cause depressions in gravitational fields by focusing gravitons. These dips in gravity cause a weakening in the fabric of space and large concentrations could potentially cause the formation of a Schwarzchild black hole, which is a black hole with no observable charge or momentum.

When amplified, the effects of the watch can cause localized gravity wells across large distances. As discovered by Paracelcus, by charging it with chronetic energy from Theodosius of Bithynia's Sundial and focusing the spacial depression into a wormhole with Pierre-Simon Laplace's Telescope, one can physically travel through time, provided a device such as H. G. Well's Time Machine is present to callibrate the destination.