From Chapter 4:
It seems likely that Richard Cromwell was a smoker. In 1689, long after he had retired into private life and had ample leisure for blowing clouds, he sent to a friend a "Boxe of tobacco," which was described as "A.J. Bod (den's) ... best Virginnea." In a letter to his daughter Elizabeth, dated 21 January 1705, there is a reference to this same dealer, whom he describes as "Adam Bodden, Bacconist in George Yard, Lumber [Lombard] Street." The allusion is worth noting as a very early instance of the colloquial trick of abbreviation familiar in later days in such forms as "baccy" and "bacca" and their compounds.

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.