Entertainment at sea was an important aspect of survival during the long periods of confinement on a ship. Culturally, expressions of entertainment can be very diverse and archaeologically, very revealing. Universally, many cultures enjoyed smoking tobacco when quantities of the natural narcotic could be obtained. Tobacco, having been introduced to Europe by the New World Indians in the late 1570's was quickly embraced by explorers and commoners, on land and sea. Sailors were known to imbibe in the use of tobacco for pleasure and perhaps medicinal purposes. Smoking pipes made of clay, often considered items of personal possession and used for trade, are commonly found on colonial period sites in North America dating from the early 1600s to the early 1800s.