An hourglass (or sandglass, sand timer, or sand clock) is a device used to measure the passage of time. It comprises two glass bulbs connected vertically by a narrow neck that allows a regulated trickle of material (historically sand) from the upper bulb to the lower one. Factors affecting the time interval measured include sand quantity, sand coarseness, bulb size, and neck width. Hourglasses may be reused indefinitely by inverting the bulbs once the upper bulb is empty. Customise the colour of sand, set the time and watch the grains of sand fall slowly as time passes. A versatile timer that can be used again and again. A beautiful minimalist digital sand timer app. Set custom times, choose activities, and find your flow with the calming hourglass animation. Perfect for work, study, breaks, and exercise. Antique hand made Sand Timer. An hourglass (or sandglass, sand timer, or sand clock) is a device used to measure the passage of time. It comprises two glass bulbs connected vertically by a narrow neck that allows a regulated trickle of material (historically sand) from the upper bulb to the lower one.
