Hi Kathleen I read that and as far as I'm concerned it's still a planet

Hi Kate history books were out of date when I went to school

Hi Deborah That's a great idea I'll give you the 10 of diamonds to hear you giggle LOL

Wow, I'm rich! We must have 20 decks of playing cards lying around somewhere. I'm still trying to figure out what I can buy with the 250,000 play-money chips I've accumulated on PokerStars. No money...just chips. Oh, well, no money in equals no money out. Cheri

Hi Larry!

I liked the others but was really interested in this one - by the way, really love your work!

Cesium Atoms at Work

"...till like a clock worn out with eating time."
John Dryden (1631-1701)

The 1955 Cesium Atomic Clock at the National Physical Laboratory, UK. It kept time to a second in 300 years.

A "cesium(-beam) atomic clock" (or "cesium-beam frequency standard") is a device that uses as a reference the exact frequency of the microwave spectral line emitted by atoms of the metallic element cesium, in particular its isotope of atomic weight 133 ("Cs-133"). The integral of frequency is time, so this frequency, 9,192,631,770 hertz (Hz = cycles/second), provides the fundamental unit of time, which may thus be measured by cesium clocks.

Now that is a clock!!!