The Earth Day supplement in Tuesday's Deseret News was very nice, but the first sentence that my eyes fell upon contains two myths that cry out to be corrected: "The amount of water on the earth today is exactly the same as it was billions of years ago when dinosaurs roamed."

The second myth is easy to correct: dinosaurs roamed millions, not billions of years ago.

The first myth suggests that water is an element, that, short of a nuclear reaction, can be neither created nor destroyed. But H2O is a compound, and it is constantly being created and destroyed. For starters, earth loses water high in the atmosphere as it is broken down into oxygen and hydrogen by ultra-violet radiation. Then there is photosynthesis, which is splitting water all the time, releasing the oxygen and using the hydrogen in other reactions. In cellular respiration, oxygen is combined with hydrogen to form nice new water molecules.

Even in the glass of water you are drinking, some water molecules are breaking down at any moment to form hydrogen ions and hydroxyl ions, which are combining at any moment to form more new water molecules. All this (and more) being the case, it is hard to imagine how a single water molecule drunk by a dinosaur those millions of years ago could have remained intact until today.

Frank B. Salisbury