A 'censer is a vessel for burning incense. A typical censer is a small metal or stone dish, often on small legs. In many cultures, burning incense has spiritual and religious connotations, and this influences the design and decoration of the censer. Designs vary from simple, earthenware bowls to intricately carved silver or gold vessels.
A famous thurible is the Botafumeiro, in the cathedral of Santiago de Compostela. Suspended from the ceiling of the cathedral, the swinging of this 5 foot high, 55 kilogram silver vessel is quite a sight, possibly only surpassed by the spectacle of a lone man hurling himself at the swinging vessel to bring it to a stop.
One of the explanations for the great size of the Botafumeiro is that in the early days it was used to freshen the air in the cathedral after being visited droves of travel-weary pilgrims.