From Chapter 3:
The number of shops where tobacco was sold in the early days of its triumph seems to have been extraordinary. Barnaby Rich, one of the most prolific parents of pamphlets in an age of prolific writers, wrote a satire on "The Honestie of this Age," which was printed in 1614. In this production Rich declares that every fellow who came into an ale-house and called for his pot, must have his pipe also, for tobacco was then a commodity as much sold in every tavern, inn and ale-house as wine, ale, or beer. He goes on to say that apothecaries' shops, grocers' shops, and chandlers' shops were (almost) never without company who from morning to night were still taking tobacco; and what a number there are besides, he adds, "that doe keepe houses, set open shoppes, that have no other trade to live by but by the selling of tobacco." Rich says he had been told that a list had been recently made of all the houses that traded in tobacco in and near about London, and that if a man might believe what was confidently reported, there were found to be upwards of 7000 houses that lived by that trade; but he could not say whether the apothecaries', grocers' and chandlers' shops, where tobacco was also sold, were included in that number. He proceeds to calculate what the annual expenditure on smoke must be. The number of 7000 seems very large and is perhaps exaggerated. Round numbers are apt to be over rather than under the mark.

From Chapter 5:
Among the many medicinal virtues attributed to tobacco was its supposed value as a preservative from contagion at times of plague. Hearne, the antiquary, writing early in 1721, said that he had been told that in the Great Plague of London of 1665 none of those who kept tobacconists' shops suffered from it, and this belief no doubt enhanced the medical reputation of the weed. I have also seen it stated that during the cholera epidemics of 1831, 1849, and 1866 not one London tobacconist died from that disease; but good authority for the statement seems to be lacking. Hutton, in his "History of Derby," says that when that town was visited by the plague in 1665, that at the "Headless-cross ... the market-people, having their mouths primed with tobacco as a preservative, brought their provisions.... It was observed, that this cruel affliction never attempted the premises of a tobacconist, a tanner or a shoemaker." Whatever ground there may have been for the belief in the prophylactic effect of smoking, there can be no doubt that in the seventeenth century it was firmly held. Howell in one of his "Familiar Letters" dated January 1, 1646, says that the smoke of tobacco is "one of the wholesomest sents that is against all contagious airs, for it overmasters all other smells, as King James they say found true, when being once a hunting, a showr of rain drave him into a Pigsty for shelter, wher he caus'd a pipe full to Be taken of purpose." But here Mr. Howell is certainly drawing the long-bow. One cannot imagine the author of the "Counterblaste" countenancing the use of tobacco under any circumstances.