From Chapter 4:
But to turn from this worthy Exeter citizen to more famous names: I do not know of any good evidence as to whether or not Cromwell smoked, although he is said to have taken an occasional pipe while considering the offer of the crown, but John Milton certainly did. The account of how the blind poet passed his days, after his retirement from public office, was first told by his contemporary Richardson, and has since been repeated by all his biographers. His placid day ended early. The poet took his frugal supper at eight o'clock, and at nine, having smoked a pipe and drunk a glass of water, he went to bed. Apparently this modest allowance of a daily evening pipe was the extent of Milton's indulgence in tobacco. He knew nothing of what most smokers regard as the best pipe of the day—the after-breakfast pipe.

From Chapter 6:
Other well-known men of the late seventeenth century were "tobacconists" in the old sense of the word. Sir Isaac Newton is said to have smoked immoderately; and a familiar anecdote represents him as using for the purposes of a tobacco-stopper, in a fit of absent-mindedness, the little finger of a lady sitting beside him, whom he admired, but the truth of this legend is open to doubt. Thomas Hobbes, who lived to be ninety (1588-1679), was accustomed to dine at 11 o'clock, after which he smoked a pipe and then lay down and took a nap of about half an hour. No doubt he would have attributed the length of his days to the regularity of his habits. Izaak Walton, who also lived to be ninety, as the lover of the placid and contemplative life deserved to do, loved his pipe, though he seldom mentions smoking in the "Compleat Angler." Sir Samuel Garth, poet and physician, once known to fame as the author of "The Dispensary," was another pipe-lover, as is shown by his verses quoted at the head of this chapter. Dudley, the fourth Lord North, began to smoke in 1657, and, says Dr. Jessopp, "the habit grew upon him, the frequent entries for pipes and tobacco showing that he became more and more addicted to this indulgence. Probably it afforded him some solace in the dreadful malady from which he suffered so long."