Two Actual “Scratch ’n’ Sniff” Ads:

• In 1977, the Rolls-Royce Motor Car Company introduced an ad campaign entitled “This, in Essence, Is Rolls-Royce.” The “essence”: a scent strip that was supposed to smell like leather upholstery.

• In 1989, BEI Defense Systems ran a “scratch-and-sniff” ad in the Armed Forces Journal for the Hydra 70 weapons system. The ad pictured two battling helicopters; when scratched, it gave off the smell of cordite, the odor left in the air after a rocket explosion.