The name itself—_Thalasseros_—is evidently derived from θαλασση, the sea. Fuchs, the translator of Myrepsus, avows that he can form no conjecture as to why the collyrium was termed Thalasseros (quam autem ob causam nescio). In Cornarius’ translation of Aetius, it is entered as “Thalasserum, _hoc est marinum_.” And in all probability it originally received its high-sounding and attractive appellation from the marine colour of the preparation, the hue of the collyrium being, as we have already seen, sometimes the cause and source of its distinctive appellation, as in the collyria termed _Melinum_, _Cygnus_, _Cirrhon_, etc. It has been conjectured that the name was imposed upon it in consequence of one or other of its ingredients being of marine origin. But in none of the formulæ given for it by the authors already named, does any sea ingredient enter into its composition.[489] The object of the _Thalasseros_ in our inscription was to produce clearness of vision (_ad claritatem_). It was used in vision impaired from cataract (_suffusio_) and other causes. Galen describes the _Thalasseros_ of Hermophilus as “accomodatum ad suffusiones et ad omnem hebetudinem visus; facit et ad incipientem suffusionem” (vol. xii. p. 781). Myrepsus assigns to it the powers of “lachrymas retinens, ad inchoantes suffusiones et nyctalopas, et ad recentem pupillæ dilatationem” (sect. xxiv. cap. 51). It is adapted, according to Trallianus, “ad hebetudinem, et incipientes suffusiones; et callos exterit” (lib. ii. cap. v. p. 175). 2. T. JUNIANI C_e_R_us_SOMAELINUM AD CLARITATEM.—_T. Junianus’ Leaden_ (?) _Melinum (or Golden Yellow Collyrium) for clearness of vision._ I have already had occasion to speak of the signification and qualities of the collyrium named _Melinum_. In the Colchester stamp the _Melinum_ is invested with the same supposed properties as the _Crsomelinum_ in the above legend on the Bath seal,—namely, “ad claritatem.”[490] The prefix CRSO, in _Crsomelinum_, admits of more than one interpretation. Galen gives four different formulæ for “collyria _Melina_.” Three of these contain, as one of their ingredients, the _Cerussa_, or carbonate of lead; and the prefix CRSO may possibly stand as a contraction for _Cerussa_, implying the presence of this medicine in the collyrium. And, in relation to this view, it is to be recollected that this preparation of lead was, in these ancient times, held in some esteem as a local application in eye-diseases. Galen recommends it as an anodyne in pains of the eyes, and as a general astringent and sedative application.[491]