Guano: The World's Oddest Industry

South American nitrate was a good fertilizer. It's growing in increasingly hungry European nations during the Industrial Revolution. So they fixed their attention to the place where there were mountains of the most perfect and powerful natural fertilizer ever found. During the 20 years from the 1840s to the 1960s, it fueled national economies,. determined foreign policy, caused the war, and earned a lasting reputation as one of the world's oddest industries.