Poole battery clocks are to be found in several case styles.
As a "gallery" style clock, they are rather unusual probably because the "candlestick" style with the visible pendulum motion and glass dome cover had a more novel appeal to buyers than the enclosed case styles.
The Poole battery clock was later manufactured by Barr manufacturing company and branded with the Barr name.
The Poole battery clock is a unique application of Mathias Hipp's invention that utilizes a toggle which engages when the pendulum motion decreases and the toggle "catches."
Hipp's invention used the toggle to close the battery circuit to an electromagnet which accelerated the pendulum.
Poole's toggle clock releases a weighted roller that accelerates the pendulum when the pendulum motion decreases enough for the toggle to "catch." The weighted roller is immediately reset and latched electromagnetically through the battery circuit.
Most common problem with the Poole and Barr clocks is corrosion in the battery compartment. Secondly, they won't run well with normal lubrication. So many little links and levers operate extremely quick to reset and lock the weighted roller arm. Any cohesive lubricant will dampen the reset locking action.