smoke

In 1854, the essayist Henry David Thoreau published an ode to a morning fire: "Light-winged Smoke, Icarian bird... Lark without song, and messenger of dawn." Scientists, of course, saw the hazing blue of wood smoke  - or any smoke derived from burning plant material - as something less poetic. In particular, the smoke from dried leaves of the tobacco plant attracted serious attention from chemists by the end of the 19th century. Victorian scientists had, for instance, calculated that cigarette smoke was about four percent carbon monoxide, a poisonous gas which directly interferes with the…