From Chapter 3:
"A Tobacco-Seller," says Earle, "is the onely man that findes good in it which others brag of, but do not; for it is meate, drinke, and clothes to him. No man opens his ware with greater seriousnesse, or challenges your judgement more in the approbation. His shop is the Randevous of spitting, where men dialogue with their noses, and their communication is smoake. It is the place onely where Spaine is commended, and prefer'd before England itselfe. He should be well experienc'd in the world: for he ha's daily tryall of mens nostrils, and none is better acquainted with humors. Hee is the piecing commonly of some other trade which is bawde to his Tobacco, and that to his wife, which is the flame that follows this smoke."

From Chapter 8:
The allusion in these verses to a "satiric wipe" refers to a passage in the poem entitled "Conversation," which Cowper had written in the previous year, 1781. In this passage tobacco is abused in terms which Cowper clearly felt to need modification after his personal intercourse with such a smoker as his friend Bull. In describing, in "Conversation," the manner in which a story is sometimes told, the poet says:

The pipe, with solemn interposing puff,
Makes half a sentence at a time enough;
The dozing sages drop the drowsy strain,
Then pause and puff—and speak, and pause again.
Such often, like the tube they so admire,
Important triflers! have more smoke than fire.