This book describes the heart, blood, and other parts of the body's circulatory system and explains how each component functions.

This book describes the skeletal system and outlines the many important roles that bones play in the healthy functioning of the human body.

A study of the center of the solar system discusses its composition--from its thermonuclear core to its surface to the corona--as well as its processes and role as a source of energy.

With winds that can reach speeds of three hundred miles an hour and funnel clouds that can measure a mile in diameter, tornadoes leave enormous damage in their wake. Now Seymour Simon examines these twisting columns of air and destruction. Simon explains how tornadoes are formed, why and when they are most likely to occur, how scientists classify and track them -- and what to do if one touches down. Full-color photographs show this powerful phenomenon...

This book describes the nature and work of muscles, the different kinds, and the effects of exercise and other activities on them.

Describes the physical characteristics, habits, and natural environment of various species of whales, and includes color photographs.

Describes the origins, characteristics, and future of the sun, planets, moons, asteroids, meteoroids, and comets.

Provides a brief history of horses, including how they evolved and how they have been trained by man for work, sports, warfare, and companionship. Also includes information about different varieties of horses as well as their physical attributes and their eating and breeding habits.

Examines the phenomenon of earthquakes, describing how and where they occur, how they can be predicted, and how much damage they can inflict.

Describes the physical characteristics and behavior of various kinds of gorillas.