The general reasons for killing a god or his representative have been examined in the preceding chapter. But when the god happens to be a deity of vegetation, there are special reasons why he should die by fire. For light and heat are necessary to vegetable growth; and, on the principle of sympathetic magic, by subjecting the personal representative of vegetation to their influence, you secure a supply of these necessaries for trees and crops. In other words, by burning the spirit of vegetation in a fire which represents the sun, you make sure that, for a time at least, vegetation shall have plenty of sun. It may be objected that, if the intention is simply to secure enough sunshine for vegetation, this end would be better attained, on the principles of sympathetic magic, by merely passing the representative of vegetation through the fire instead of burning him. In point of fact this is sometimes done. In Russia, as we have seen, the straw figure of Kupalo is not burned in the midsummer fire, but merely carried backwards and forwards across it.(744) But, for the reasons already given, it is necessary that the god should die; so next day Kupalo is stripped of her ornaments and thrown into a stream. In this Russian custom, therefore, the passage of the image through the fire is a sun-charm pure and simple; the killing of the god is a separate act, and the mode of killing him—by drowning—is probably a rain-charm. But usually people have not thought it necessary to draw this fine distinction; for the various reasons already assigned, it is advantageous, they think, to expose the god of vegetation to a considerable degree of heat, and it is also advantageous to kill him, and they combine these advantages in a rough-and-ready way by burning him.