Sound travels fifteen times faster through steel than through air.
134
Pumice is the only rock that floats on water.
14
Scientists aren't sure what color dinosaurs were.
312
The weight of a carat (200 milligrams), standard unit of measurement for gemstones, is based on the weight of the carob seed.
51
Iron weighs more after it rusts.
16
Research indicates that plants grow healthier when they are stroked.
173
Every day, plants convert sunlight into energy equivalent to six times the entire power consumption of human civilization.
9