In ancient times, and in all countries, the profession of physic was annexed to the priesthood. Men imagined that all their diseases were inflicted by the immediate displeasure of the Deity, and therefore concluded that the remedy would most probably proceed from those who were particularly employed in his service. Whatever, for the same reason, was found of efficacy to avert or cure distempers was considered as partaking somewhat of the Divinity. Medicine was always joined with magic: no remedy was administered without mysterious ceremony and incantation. The use of plants and herbs, both in medicinal and magical practices, was early and general. The mistletoe, pointed out by its very peculiar appearance and manner of growth, must have struck powerfully on the imaginations of a superstitious people. Its virtues may have been soon discovered. It has been fully proved, against the opinion of Celsus, that internal remedies were of very early use.[9] Yet if it had not, the practice of the present savage nations supports the probability of that opinion. By some modern authors the mistletoe is said to be of signal service in the cure of certain convulsive distempers, which, by their suddenness, their violence, and their unaccountable symptoms, have been ever considered as supernatural. The epilepsy was by the Romans for that reason called _morbus sacer_; and all other nations have regarded it in the same light. The Druids also looked upon vervain, and some other plants, as holy, and probably for a similar reason. The other objects of the Druid worship were chiefly serpents, in the animal world, and rude heaps of stone, or great pillars without polish or sculpture, in the inanimate. The serpent, by his dangerous qualities, is not ill adapted to inspire terror,--by his annual renewals, to raise admiration,--by his make, easily susceptible of many figures, to serve for a variety of symbols,--and by all, to be an object of religious observance: accordingly, no object of idolatry has been more universal.[10] And this is so natural, that serpent-veneration seems to be rising again, even in the bosom of Mahometanism.[11]