The oldest conception of the vegetation-spirit was that of a tree-spirit which had power over rain, sunshine, and every species of fruitfulness.  For this reason a tree had a prominent place both in the Beltane and Midsummer feasts.  It was carried in procession, imparting its benefits to each house or field.  Branches of it were attached to each house for the same purpose.  It was then burned, or it was set up to procure benefits to vegetation during the year and burned at the next Midsummer festival.[935] The sacred tree was probably an oak, and, as has been seen, the mistletoe rite probably took place on Midsummer eve, as a preliminary to cutting down the sacred tree and in order to secure the life or soul of the tree, which must first be secured before the tree could be cut down.  The life of the tree was in the mistletoe, still alive in winter when the tree itself seemed to be dead.  Such beliefs as this concerning the detachable soul or life survive in Maerchen, and are still alive among savages.[936]

Folk-survivals show that a human or an animal representative of the vegetation-spirit, brought into connection with the tree, was also slain or burned along with the tree.[937] Thus the cutting of the mistletoe would be regarded as a preliminary to the slaying of the human victim, who, like the tree, was the representative of the spirit of vegetation.

The bonfire representing the sun, and the victims, like the tree, representing the spirit of vegetation, it is obvious why the fire had healing and fertilising powers, and why its ashes and the ashes or the flesh of the victims possessed the same powers.  Brands from the fire were carried through the fields or villages, as the tree had been, or placed on the fields or in houses, where they were carefully preserved for a year.  All this aided growth and prosperity, just as the smoke of the fire, drifting over the fields, produced fertility.  Ashes from the fire, and probably the calcined bones or even the flesh of the victims, were scattered on the fields or preserved and mixed with the seed corn.  Again, part of the flesh may have been eaten sacramentally, since, as has been seen, Pliny refers to the belief of the Celts in the eating of human flesh as most wholesome.

In the Stone Age, as with many savages, a circle typified the sun, and as soon as the wheel was invented its rolling motion at once suggested that of the sun.  In the Edda the sun is “the beautiful, the shining wheel,” and similar expressions occur in the Vedas.  Among the Celts the wheel of the sun was a favourite piece of symbolism, and this is seen in various customs at the Midsummer festival.  A burning wheel was rolled down a slope or trundled through the fields, or burning brands were whirled round so as to give the impression of a fiery wheel.  The intention was primarily to imitate the course of the sun through the heavens, and so, on the principle of imitative magic, to strengthen