A long frame with two glass bulbs containing sand
An Hourglass is a long frame with two glass bulbs filled with sand. It is a tool used for measuring the passage of time. The amount of time measured is dependent on the size of hourglass and can vary from seconds to hours.
Tempus used an hourglass to measure time. He was sent to kill the Charmed Ones by the Source of All Evil and worked with another demon, Inspector Rodriguez. Tempus used the hourglass to trap the sisters in a Time loop, giving Rodriguez several chances to kill the sisters and reversing time each time he failed.