The waters of the island of Ænaria are curative of urinary calculi,[1] it is said; and the same is the case with the cold spring of Acidula,[2] four miles distant from Teanum[3] Sidici- num, the waters at Stabiæ, known as the Dimidiæ,[4] and those in the territory of Venafrum,[5] which take their rise in the spring of Acidula. Patients suffering from these complaints may be cured also by drinking the waters of Lake Velia;[6] the same effects being produced by those of a spring in Syria, near Mount Taurus, M. Varro says, and by those of the river Gallus in Phrygia, as we learn from Callimachus. In taking the waters, however, of this last, the greatest moderation is necessary, as they are apt to cause delirium; an effect equally produced, Ctesias tells us, by the waters of the Red Fountain[7] in Æthiopia.