CORK, the bark of a tree of the same name; Quercus Suber, Lin.
In order to take off the bark, an incision is made from the top to the bottom of the tree, and at each extremity another round the tree, perpendicular to the first. When the tree is fifteen years old, it may be barked for eight years successively; and the quality of the bark improves with the age of the tree. When stripped from the tree, which does not therefore die, the bark is piled up in a pond or ditch, and loaded with heavy stones to flatten it, and reduce it into a tabular form. It is then removed to be dried; and when sufficiently dry, put in bales for carriage. If care be not taken to strip the bark, it splits and peels of itself, being pushed up by another bark formed underneath.
The cork tree, and the uses to which the bark may be applied, were known both to the Greeks and Romans. Pliny informs us that the Romans employed it to stop all kinds of vessels; but the use of it for this purpose does not appear to have been common till the invention of glass bottles, of which, according to Professor Beckman, there is no mention before the fifteenth century.
Other vegetable productions have been sometimes employed instead of cork. The spondias lutea, a tree which grows in South America, particularly in moist places, and which is there called monbin or monbain, is sometimes brought to England for the purpose of stopping vessels. The roots of liquorice are applied to the same use, and on this account the plant is much cultivated in Sclavonia, and exported to other countries. A tree called nyssa, which grows in North America, has been found also to answer as a substitute for cork.