Snedden, Robert

Discusses the roles and duties of dogs and horses that help police track fugitives, sniff out drugs and bombs, or help with crowd control, and explores their selection, training, and off-duty care.

Discusses how mechanical engineers design and innovate machines, and explains the steps they follow in the engineering design process.

Explains the causes and limits of variation in a species, and why variation is so important to their survival.

Explores the history, culture, and traditions of the ancient Aztec, Inca, and Maya peoples of Mesoamerica.

Covers the inventions and technology of the ancient Roman Empire and how their ideas influenced modern technology.

Photographs and illustrations introduce the inventions and technology used by the ancient Greeks, describing how those ideas influenced later technology.

Covers the inventions and technology used by ancient Egyptians and how their ideas influenced technology today.

Covers the inventions and technology used in ancient China and how their ideas influenced technology today.

Discusses such infectious diseases as rabies, smallpox, AIDS, influenza, and malaria and describes how they are transmitted and treated.

Discusses the beneficial uses of bacteria in applications ranging from brewing and baking to industry and sewage treatment.