From Chapter 3:
Trickery of another kind is revealed in a scene in Chapman's play "A Humorous Day's Mirth," 1599. A customer at an ordinary says: "Hark you, my host, have you a pipe of good tobacco?" "The best in the town," says mine host, after the manner of his class. "Boy, dry a leaf." Quietly the boy tells him, "There's none in the house, sir," to which the worthy host replies sotto voce, "Dry a dock leaf." But the diner's potations must have been powerful if they had left him unable to distinguish between the taste of tobacco and that of dried dock-leaf.

From Chapter 5:
The belief in the prophylactic power of tobacco was, however, very generally held. When Mr. Samuel Pepys on June 7, 1665, for the first time saw several houses marked with the ominous red cross, and the words "Lord, have mercy upon us" chalked upon the doors, he felt so ill at ease that he was obliged to buy some roll tobacco to smell and chew. There is nothing to show that Pepys even smoked, which considering his proficiency in the arts of good-fellowship, is perhaps a little surprising. Defoe, in his fictitious but graphic "Journal of the Plague Year in London," says that the sexton of one of the London parishes, who personally handled a large number of the victims, never had the distemper at all, but lived about twenty years after it, and was sexton of the parish to the time of his death. This man, according to Defoe, "never used any preservative against the infection other than holding garlic and rue in his mouth, and smoking tobacco."