Further, in favour of the present supposition, that the collyrium of the inscription may possibly be named from the DRYS, I may take the present opportunity of mentioning that the ancient Roman oculists seem to have pursued, in regard to old cicatrices of the eye, a treatment which is not followed by their successors in modern times. “All cicatrices on the transparent part of the eye,” says Aetius, “appear white (omnes cicatrices in nigro oculi _albæ_ apparent”);[494] and consequently give, by their presence, a disagreeable and disfiguring effect to the eye.[495] Some of the Roman oculists seem to have used various collyria, for the purpose of dyeing or changing the colour of these white specks or pearly cicatrices, and of thus imparting to them some kind of tint that rendered the appearance of the eye, and the distinction between the transparent cornea and its white opacities, less marked and striking. For this purpose the gall-nuts of the oak or DRYS appear to have been greatly used. Aetius does not approve of the practice of tinting cicatrices; but, in a chapter bearing the heading of “Albuginum Tincturæ,” he describes half-a-dozen applications and collyria that might be employed for the purpose of staining and correcting the colour of old cicatrices of the eyes, lest, he adds, his readers should be ignorant of the means which might effect this (ut ne ignorentur ea quæ hoc facere possunt). In three or four of these collyria the gall-nut forms a leading ingredient,[496] and it seems to have been generally used previously to, or in combination with, blue vitriol (_atramentum sutorium_). Myrepsus gives a “collyrium tingens crassas albugines et cicatrices,” containing galls with chalcanthus (or copperas), roasted lead, etc.; and a second formed of burnt and washed lead, etc., combined with unripe galls.[497] Paulus Ægineta mentions two dyes for cicatrices, both of them containing galls along with chalcanthus.[498] Alexander Trallianus gives a collyrium for staining cicatrices, which he pronounces “valde generosum.” It consists principally of chalcanthus and galls.[499] Lastly, let me offer one more conjecture. If the debateable word in this legend be correctly copied as DIEXUM into the Antiquarian Society minute-book, it may probably signify the collyrium DIOXUS or DIOXUM given by Marcellus, and which he recommends for the removal of granulations of the eyelids. This collyrium was composed of cadmia, burnt copper, hæmatites, myrrh, and gum.[500] 4. T. JUNIANI HOBSUM AD ρUECUMO DELICTA A MEDICIS.