A substance is anhydrous if it contains no water, for example, salts lacking their water of crystallisation. The way of achieving the anhydrous form differs from one substance to another.
A partial solar eclipse at its peak at 3:37 p.m. in Mesa on Oct. 23, 2014. The eclipse was visible over most of North America and covered 44 percent of the Arizona sun. Michael Chow/The Republic.
Total solar eclipse of 2017. Eclipse maps of the path of totality on August 21, 2017. This is your guide to the solar eclipse and where you need to be. National eclipse maps. The total solar eclipse occurs only within the yellow path as shown in this map.