At Home: A Short History of Private Life

by Bill Bryson

Potatoes, the other great food crop of the New World, present an almost equally intriguing batch of mysteries. Potatoes are from the nightshade family, which is of course notoriously toxic, and in their wild state they are full of poisonous glycoalkaloids—the same stuff, at lower doses, that puts the zip in caffeine and nicotine. Making any wild potatoes safe to eat required reducing the glycoalkaloid content to between one-fifteenth and one-twentieth of its normal level. This raises a lot of questions, beginning most obviously with: How did they do it? And while they were doing it, how did they know they were doing it? How do you tell that the poison content has been reduced by, say, 20 percent or 35 percent or some other intermediate figure? How do you assess progress in such a process? Above all, how did they know that the whole exercise was worth the effort and that they would get a safe and nutritious foodstuff in the end?