CHAP. 22.—THE IMPURITIES OF WATER.
Slime[3017] is one great impurity of water: still, however, if a river of this description is full of eels, it is generally looked upon as a proof[3018] of the salubrity of its water; just as it is regarded as a sign of its freshness when long worms[3019] breed in the water of a spring. But it is bitter water, more particularly, that is held in disesteem, as also the water which swells the stomach the moment it is drunk, a property which belongs to the water at Trœzen. As to the nitrous[3020] and salso-acid[3021] waters which are found in the deserts, persons travelling across towards the Red Sea render them potable in a couple of hours by the addition of polenta, which they use also as food. Those springs are more particularly condemned which secrete mud,[3022] or which give a bad complexion to persons who drink thereof. It is a good plan, too, to observe if water leaves stains upon copper vessels; if leguminous vegetables boil with difficulty in it; if, when gently decanted, it leaves an earthy deposit; or if, when boiled, it covers the vessel with a thick crust.[3023]
It is a fault also in water,[3024] not only to have a bad smell,[3025] but to have any flavour[3026] at all, even though it be a flavour pleasant and agreeable in itself, or closely approaching, as we often find the case, the taste of milk. Water, to be truly wholesome, ought to resemble air[3027] as much as possible. There is only one[3028] spring of water in the whole universe, it is said, that has an agreeable smell, that of Chabura, namely, in Mesopotamia: the people give a fabulous reason for it, and say that it is because Juno[3029] bathed there. Speaking in general terms, water, to be wholesome, should have neither taste nor smell.