In 1845, the sixth US President, John Quincy Adams, wrote a letter to Rev. Samuel Cox in Brooklyn, who was in the process of writing a book about tobacco and smoking. Adams told Cox that when he was a young man, he had been addicted to both smoking and chewing tobacco. When he decided to quit it took him three months.

He wrote:

'I have often wished that every individual afflicted with this artificial passion could force it upon himself to try but for three months the experiment which I made, sure that it would turn every acre of tobacco land into a wheat field, and add five years to the average of human life'.

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