From: utzoo!decvax!harpo!duke!mcnc!jwb Newsgroups: net.physics Title: Re: perpetual motion puzzle? Article-I.D.: mcnc.1470 Posted: Mon Jan 17 10:37:02 1983 Received: Wed Jan 19 05:31:41 1983 References: fortune.726,sdcsvax.57 I have one of the clocks with the clear (glass in my case) which supports the hands. I found it in my parents' attic. I have had to fix it several times so I know how it works. A regular clock motor is in the base. It has a conventional gear. Glued to the glass is a large gear hidden in the outer shell of the clock It's sort of like a rack and pinion made into a circle. Thus the entire glass rotates. The minute hand travels through friction with the glass. It's not rigid so you can set the clock. The hour hand is connected through a series of gears with a weight so it achieves a virtual movement which corresponds to 1/60 the speed of the minute hand. This may be more than anyone wanted to know, but it is how it works. Jack Buchanan