The Incense reference article from the English Wikipedia on 24-Jul-2004
(provided by Fixed Reference: snapshots of Wikipedia from wikipedia.org)

Incense

For thoughtful child sponsors
Incense is a preparation of aromatic plant matter, often with the addition of essential oils extracted from plant or animal sources, intended to release fragrant smoke for religious, therapeutic or simply aesthetic purposes as it smolders. Incense is either thrown onto hot coals or into a censer or thurible as a powder, or processed into more convenient stick, cone or wedge form.
Incense was traditionally used as a timing device in ancient ChinaEnlarge

Incense was traditionally used as a timing device in ancient China

Fragrances used include: