Another precept, which might well have been made by an English board of health in the nineteenth century, is not to pollute water by throwing impure matter into it. The only special Parsee rites which would be unsuited for modern European society, are the worship of the sacred fire and the disposal of the dead. It is true that the former is distinctly understood to be merely a symbol of the Deity, and used exactly as water is in baptism, or as the ascending flame of candles and smoke from swinging incense are in the Catholic ritual, to bring more vividly before the minds of the worshippers the idea of the spirit soaring upwards towards heaven. Still, in modern society fire is too well understood as merely a particular form of chemical combination, and is too familiar as the strong slave and household drudge of man, to acquire a leading place in a religious ritual where it has not been hallowed by the usage of a long line of ancestors and the traditions of a venerable antiquity. All that can be said is, that if religious rites and ceremonies are to be maintained in an age when science has become the prevailing mode of thought, appropriate symbolism, especially that of music, must more and more take the place of appeals to the intellect on metaphysical questions, and of repetitions of traditional formulæ which have lost all living significance. Another Parsee rite, which is even less adapted for general usage, is that of disposing of the dead on towers of silence, where the body moulders away or is devoured by birds of prey. It originates in a poetical motive of not defiling the pure elements, fire, earth, or water, by corruption; but it is obviously unsuited for the conditions of civilisation and climate which prevail in crowded cities under a humid sky. There is little prospect therefore of any general conversion to the sect of Zoroastrians; but what seems probable is the gradual transformation of existing modes both of religious and secular thought into something which is, in principle, very closely akin to the ‘excellent religion’ taught by the Bactrian prophet.