1.12 min. | 4.306667 user rating
Found this very interesting clock in a section of the British Museum - London. To all the people are writing it's not a perpetual motion machine, I KNOW, IT'S NOT. 'Rolling Ball Clock' only wouldn't have attracted over 2800 to watch the video! The video has been done simply because THIS CLOCK IS COOL. From the tag in front of this masterpiece: "Rolling Ball Clock - Santiago James Moore French. Royal Exchange, London about 1820 Santiago James Moore French was one of several clockmakers to follow an original design by Sir William Congreve. The steel ball takes 30 seconds to roll from one end of the table to the other. At each end a catch is released, enabling the spring driven movement to tip the table the other way and start the ball rolling back. The ball travels about 4000 Km a year." Updated on 10th April 2008: Got this email from Mr Oliver at the British Museum: Unfortunately this clock cannot be called a perpetual motion machine. It has a source of energy, a coiled steel spring. The spring is encased in a brass barrel and is part of the movement of the clock, which is located above the rolling ball. Every time the ball hits the lever at the end of the track, the spring powers the movement to raise that end of the platter, thus lifting the ball and causing it to roll back again. I wind the clock every week (which means I put my energy from my breakfast into the spring!), so you can see that this is not perpetual motion. You are correct about friction - if there was no ...

2.37 min. | 4.84 user rating
This is a video of my Atmos clock. The Atmos clock is very cool in that it runs purely off of small changes in temperature and/or atmospheric pressure. There is a accordion shaped bellow that contains an inert gas and ethyl chloride. Ethyl chloride expands and contracts quite a bit in the temperature range normally found in a house. The say that a change in temperature of one degree (which will almost always happen naturally in your house in the course of a day) will power the clock for two days. The clock is engineered to be virtually friction free so it takes very little power to operate. They say that it is so sensitive (and the parts are so precise) that if a fly landed on the minute hand it would put the clock out of balance enough to stop it. All the parts are brass that is gold plated. Unfortunately the gold plating is something like three thousandths of a millimeter so it rubs off easily, which can be seen on the case of my clock. On the inside it is perfect though, having been protected by the case.