Optical illusions allow readers to see something which isn't really there!
Abbie Burgess was the daughter of a lighthouse keeper along the rocky Maine coast. In the 1850s, she heroically kept the lights burning during a month-long storm while her father was away.
An amazing woman who figured out the mathematical equations to predict the patterns of vibrations that create sound.
This excellent biography of oceanographer Sylvia Earle includes information about sound and light waves in water.