It must have been for reasons of the kind I have referred to (though doubtless religious grounds were imagined for the practice, for those were times when there was no other way of thinking about or of putting such matters) which led the Egyptian Priesthood to abstain, in their own persons, from the use of woollen garments. Habiliments of this material, from their condition not being readily ascertainable by the eye, and from their not being chilly to the skin when saturated with perspiration, are less likely to be frequently washed than those which are made of vegetable fibres. It is much the same with silk and leather. We know that in the Middle-Ages, woollens, which were then very much in use next to the skin, were not very frequently washed, though the soap which would have thoroughly cleansed them, had then been known for centuries, for it had been an old invention of the Germans, among whom the Romans had found it in use. The same negligence we may be sure had existed to an equal, or greater, extent in all the old world. At that time the washing, especially, of woollens was costly, and could only have been insufficiently accomplished. The Egyptians, we know, used alkaline preparations for rendering soluble the animal matter their clothes had contracted by being worn, that is to say for washing them. They were probably also acquainted with the solvent and detergent properties of the animal appliance which the Emperor Vespasian was bantered for having excised. We may suppose this because its washing power is referable to the alkaline matter contained in it, which was just what they were in the practice of collecting for washing their clothes; and also because the supply derived from the camel was known to be particularly effective for this purpose. In passing, the unsavoury tax just referred to was imposed as a method of making the scourers, so large and important a trade at Rome that they had their own quarter of the city, pay for licences to carry on their business, in such a manner that in each case the cost of the licence should be proportioned to the amount of business carried on. This was effected by taxing the chief material employed in the trade. The impost must have been productive, for it was retained as an item of Roman excise for two centuries. These were means, however, which were never likely to have been turned to much account, anywhere, by the mass of the people. The consequences, of course, would be serious. The animal matter that accumulated, and was decomposed in such clothing, so used, must to some extent have been reabsorbed through the pores of the skin; and so have been the fruitful source of cutaneous, and other disorders. Probably this was the very cause why our forefathers were visited so frequently by the plague, and jail fevers. The priests of old Egypt quite understood how prejudicial to health, particularly in that climate, are all practices of this kind; and they felt that it behoved them, as the