After the death of Galen came the Gothic invasions over the civilized world, and all but extinguished the learning of the times. Medicine lingered still in Rome, Constantinople, and Alexandria, but individuals rather than schools and sects kept it alive; it struggled to exist amidst the grossest ignorance, superstition, and magical practices, till it was re-invigorated by the Saracens. Saints COSMAS and DAMIAN (_circ._ 303) were brothers who studied the sciences in Syria, and became eminent for their skill in the practice of medicine. As they were Christians, and eager to spread the faith which they professed, they never took any fees, and thus came to be called by the Greeks _Anargyri_ (without fees). The two brothers suffered martyrdom under the Diocletian persecution, and have ever since been famous as workers of miracles of healing and patrons of medical science. Their relics were everywhere honoured, and a church built in Rome by St. Gregory the Great preserves them to this day. Dr. Meryon points out[510] that Gregory the Great enunciated one great doctrine of homœopathy: “Mos medicinæ est ut aliquando similia similibus, aliquando contraria contrairiis curet. Nam sæpe calida calidis, frigida frigidis, sæpe autem frigida calidis, calida frigidis sanare consuevit.” ALEXANDER OF TRALLES, though one of the most eminent ancient physicians, believed in charms and amulets. Here are a few specimens. For a quotidian ague, “Gather an olive leaf before sunrise, write on it with common ink κα, ροι, α, and hang it round the neck” (xii. 7, p. 339); for the gout, “Write on a thin plate of gold, during the waning of the moon, μεί, θρεύ, μόρ, φόρ, τεύξ, βαίν, χωώκ” (xi. l. p. 313). He exorcised the gout thus: “I adjure thee by the great name Ἰαὼ Σαβαώθ,” that is, יְהֹוָה צְבָאוֹת and a little further on: “I adjure thee by the holy names Ἰαὼ, Σαβαὼθ, Ἀδωναὶ, Ἐλωὶ,” that is אֲדֹנָי אֱלֹהָי יְהֹוָה צְבָאוֹת.[511]