The title of this book is derived from the book of Leviticus, chapter 18 vs 24 & 25: Defile not ye yourselves in any of these things: for in all these the natio

Preface, by R.S. Lull.--The origin of the earth, by J. Barrell.--The earth's changing surface and climate, by C. Schuchert.--The origin of life, by L.L. Woodruf

Discusses how many people the earth can support in terms of economic, physical, and environmental aspects.

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