Aromatherapy

 "Odour is a story of language, of man's efforts to find words to express emotion and sensation. It is allied with all the senses, indissolubly with taste, with colour, sound and memory, and deeply affected by the psychological phenomenon, the power of suggestion."
Edward Sagarin

Aromatherapy is using essential oils to relieve stress and promote relaxation and thus induce sleep. They can be used by putting a few drops in the bath (three to six drops added to bath water), diluted in vegetable oil it for massaging (12 or 13 drops in 25mls of oil) or in the case of lavender, the dried buds in a pillow.
Or just simply a couple of drops on the pillow.
The most commomnly used essential oils in aromatherapy for relaxation are Roman Chamomile and Lavender.