Hooke was good friends with the adventurer Captain Robert Knox, who often traveled to distant lands to acquire strange plants and other curiosities. One such curiosity, brought back to London in 1689, was a quantity of “bangue,” or marijuana. In Hooke’s diary entry from October 24, 1689, he describes it as a “wood spongy like a rush. beset with thornes 2 inch long & sharp like furs…” This plant was “accounted very wholsome. though for a time it takes away the memory & understanding.” In December, he gave the Royal Society a lecture on cannabis:
… The Vertues, or Quality thereof, are [in India] very well known; and the Use thereof (tho’ the Effects are very strange, and, at first hearing, frightful enough) is very general and frequent: and the Person, from whom I received it, hath made very many Trials of it, on himself, with very good Effect.
But cannabis, although wonderful, was only rarely available. Hooke tended to prefer opiates for a good night’s sleep.