"[Plin. Nat. 22.12.] - TWO VARIETIES OF THE TRIBULUS; TWELVE REMEDIES.
Of the two kinds of tribulus, the one is a garden plant, the other grows in rivers only. There is a juice extracted from them which is employed for diseases of the eyes, it being of a cool and refreshing nature, and, consequently, useful for inflammations and abscesses. Used with honey, this juice is curative of spontaneous ulcerations, those of the mouth in particular; it is good also for affections of the tonsils. Taken in a potion, it breaks calculi of the bladder. The Thracians who dwell on the banks of the river Strymon feed their horses on the leaves of the tribulus, and employ the kernels as an article of food, making of them a very agreeable kind of bread, which acts astringently upon the bowels. The401 root, if gathered by persons in a state of chastity and purity, disperses scrofulous sores: and the seed, used as an amulet, allays the pains attendant upon varicose veins: pounded and mixed with water, it destroys fleas.”
(The Natural History. Pliny the Elder. John Bostock, M.D., F.R.S. H.T. Riley, Esq., B.A. London. Taylor and Francis, Red Lion Court, Fleet Street. 1855.)