From Chapter 1:
It may further be added that though the use of tobacco was known and practised on the continent of Europe for some time before smoking became common in England—it was taken to Spain from Mexico by a physician about 1560, and Jean Nicot about the same time sent tobacco seeds to France—yet such use was exclusively for medicinal purposes. The smoking of tobacco in England seems from the first to have been much more a matter of pleasure than of hygiene.

From Chapter Chapter 8:
Cowper then goes on to attack tobacco in lines which show how unpopular smoking at that date was with ladies, and which have since often been quoted by anti-tobacconists with grateful appreciation:

Pernicious weed! whose scent the fair annoys,
Unfriendly to society's chief joys,
Thy worst effect is banishing for hours
The sex whose presence civilizes ours;
Thou art indeed the drug a gardener wants,
To poison vermin that infest his plants,
But are we so to wit and beauty blind,
As to despise the glory of our kind,
And show the softest minds and fairest forms
As little mercy as the grubs and worms?

Notwithstanding this "satiric wipe," it is not likely that Cowper would have had much sympathy with John Wesley, who, in his detestation of what had been his father's solace at Epworth, forbade his preachers either to smoke or to take snuff.