Ferrum accensum igni, nisi duretur ictibus, corrumpitur. rubens non est habile tundendo neque antequam albescere incipiat. aceto aut alumine 150inlitum fit aeri simile. a robigine vindicatur cerussa et gypso et liquida pice. haec est ferro a Graecis antipathia dicta. ferunt quidem et religione quadam id fieri et exstare ferream catenam apud Euphraten amnem in urbe, quae Zeugma appellatur, qua Alexander Magnus ibi iunxerit pontem, cuius anulos, qui refecti sint, robigine infestari, carentibus ea prioribus.151
XLIV. Medicina e ferro est et alia quam secandi. namque et circumscribi circulo1 terve circumlato mucrone et adultis et infantibus prodest contra noxia medicamenta, et praefixisse in limine evulsos sepulchris clavos adversus nocturnas lymphationes, pungique leviter mucrone, quo percussus homo sit, contra dolores laterum pectorumque subitos, qui punctionem adferant. quaedam ustione sanantur, privatim vero canis rabidi morsus, quippe etiam praevalente morbo expaventesque potum usta plaga ilico liberantur. calfit etiam ferro candente potus in multis vitiis, privatim vero dysentericis.152
XLV. Est et robigo ipsa in remediis, et sic proditur
Iron that has been heated by fire is spoiled unless it is hardened by blows of the hammer. It is not suitable for hammering while it is red hot, nor before it begins to turn pale. If vinegar or alum is sprinkled on it it assumes the appearance of copper. It can be protected from rust by means of lead acetate,a gypsum and vegetable pitch; rust is called by the Greeks ‘antipathia,’ ‘natural opposite’ to iron. It is indeed said that the same result may also be produced by a religious ceremony, and that in the city called Zeugmab on the river Euphrates there is an iron chain that was used by Alexander the Great in making the bridge at that place, the links of which331 b.c. that are new replacements are attacked by rust although the original links are free from it.
XLIV. Iron supplies another medicinal serviceMedicinal uses of iron. besides its use in surgery. It is beneficial both for adults and infants against noxious drugs for a circle to be drawn round them with iron or for a pointed iron weapon to be carried round them; and to have a fence of nails that have been extracted from tombs driven in in front of the threshold is a protection against attacks of nightmare, and a light prick made with the point of a weapon with which a man has been wounded is beneficial against sudden pains which bring a pricking sensation in the side and chest. Some maladies are cured by cauterization, but particularly the bite of a mad dog, inasmuch as even when the disease is getting the upper hand and when the patients show symptoms of hydrophobia they are relieved at once if the wound is cauterized. In many disorders, but especially in dysenteric cases, drinking water is heated with redhot iron.
XLV. The list of remedies even includes rust