Soil / Burrud, John

Examines the structure and history of Earth from the perspective of visitors from a distant galaxy, focusing on different types of soil, their formation, components, and conservation; and includes an investigation of the relationship between the size of soil particles and their permeability.

Describes the formation of soil, the components of different kinds of soil, how soil sustains plant and animal life, and how farmers and others are using modern technology to fight erosion; and presents a hands-on demonstration about the size and permeability of soil particles.