Even if documentary evidence of the New World origin of tobacco were lacking, its importance in the religious and ceremonial life of the Indians would leave little doubt of the antiquity of its use among them. Among all the tribes east of the Rocky Mountains tobacco was the favorite offering to the supernatural powers, and among the Central Algonquians no ceremony could take place without it. As a sacrifice it might be burned as incense, cast into the air or on the ground, or buried. There were sacred places at which every visitor left a tobacco offering, and during storms it was thrown into lakes and rivers to appease the under-water powers. Smoking was indulged in on all solemn occasions, such as councils, and was a necessary part of most religious ceremonies. In such ceremonial smoking the methods of picking up, filling, and lighting the pipe were usually rigidly prescribed, and the first smoke was offered to the spirits. The methods of passing and holding the pipe were also prescribed and differed with the ceremony and even with the personal taboos of the smokers. In the religious ceremonies of the Hopi, the head chief was attended by an assistant of nearly equal rank, who ceremonially lighted the pipe, and with certain formalities and set words handed it to the chief, who blew the smoke to the world quarters and over the altar as a preliminary to his invocation. The so-called medicine-bundles, collections of sacred objects around which the religious life of many of the Central Algonquians and Plains Tribes centered, often contained pipes which were smoked in the ceremonies attending the opening of the bundle (Pl. V, Nos. 1–2). In some cases the pipe itself seems to have been the most important object, and the palladium of the Arapaho tribe is a straight pipe of black stone. Among some of the eastern Siouan tribes each clan had its sacred pipe which was used at namings and other clan ceremonies. The stems of these pipes were covered with elaborate wrappings and other ornaments which symbolized the various supernatural powers invoked in the ceremonies, and the sanctity of the pipe lay in its stem rather than its bowl.