From Chapter 4:
Whether the use of tobacco prevailed as generally among the Cavalier forces is less certain; but as King Charles hated the weed, courtiers may have frowned upon its use. One distinguished cavalier, however, either smoked his pipe, or proposed to do so, on a historic occasion. In Markham's "Life of the Great Lord Fairfax" there is a lively account of how the Duke, then Marquis, of Newcastle, with his brother Charles Cavendish, drove in a coach and six to the field of Marston Moor on the afternoon before the battle. His Grace was in a very bad humour. "He applied to Rupert," says Markham, "for orders as to the disposal of his own most noble person, and was told that there would be no battle that night, and that he had better get into his coach and go to sleep, which he accordingly did." But the decision as to battle or no battle did not rest with Prince Rupert. Cromwell attacked the royal army with the most disastrous results to the King's cause. His Grace of Newcastle woke up, left his coach, and fought bravely, being, according to his Duchess, the last to ride off the fatal field, leaving his coach and six behind him.

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.