Branley, Franklyn Mansfield

Explains briefly why an object floats or sinks.

Explains in simple text and illustrations what is known about the force of gravity.

Describes how sunshine and the tilt of the earth's axis are responsible for the changing seasons.

Discusses why earthquakes happen, what their sometimes devastating effects can be, where the danger zones are, and what measures people can take to safeguard themselves.

A child explains the location of the Big Dipper, Little Dipper, and North Star.

Discusses the sun and the solar system, comparing how they were perceived in earlier times with what is known about them now.

Discusses the origins and characteristics of the natural satellites that travel around seven of the nine planets.

Explains simply some basic principles involved in space flight.

Explains in simple terms the function and importance of roots and root hairs on a plant.

A simple explanation of how the rotation of the earth causes night and day.