An energy free time keeping device which runs on chromatography.
This noiseless device is perfect for a distracted student or worker.
Over the course of an hour the soluble ink travels up the paper. The hight of the ink indicates the amount of time that has passed.
Lift glass body to refill water till mark. Insert paper cartridge into inner glass tube.
The easily removable paper cartridges can be used to keep track of the time spent at the users work station.