Only one left!
Newton's Gravity Glass is a sand-filled hourglass suspended in a liquid-filled glass cylinder. The chrome Gravity glass is an awesome desk-topper and a question-generating educational tool. When the cylinder is flipped, the sand within the hourglass moves down while the hourglass itself floats up. Standing 8" tall, this metal timer is sturdy and well crafted. Watch it in action!: Newton's Gravity Glass Video
Specifications:
- 1.5"D x 8"H
- Approximately 1-2 minute with white sand
The hour glass is very nice looking, but it is supposed to get torqued in the water filled tube until it becomes top buoyant from sand flowing from top to bottom then float to the top. This is the puzzling physics conundrum it creates (if you're unaware of the torque caused by the bottom buoyancy). The glass sent floats immediately upon being flipped. Little disappointed, but it is nice enough looking it will sit on my desk none the less.