1.   A staunch believer in the Greek idea of atomism, Kepler wondered how water particles stacked themselves to form symmetrical snowflakes.

2.   Scientists said the wispy clouds contained icy water particles and had a blue tint.

3.   While Summers flew, other scientists operated special radar stations that could directly measure the size and shape of water particles in every cloud.

4.   Experts say the germ, spread through the air via tiny water particles, kills in six people it infects.

5.   Experts say the germ, spread through the air via tiny water particles, kills one of every six people it infects.

6.   Spread through the air via tiny water particles, experts say they kill one of every six people infected.

7.   The source has not yet been confirmed, but may have been a drinking fountain, a decorative water curtain or water particles spread by sprinklers, Bod said.