Ophthalmia is one of the commonest diseases in Tibet. When so affected the sufferer either wears Chinese smoked glasses or eye shades (migra) of horsehair. These eye shades consist in a band of closely woven horse-hair about 2.5 inches broad. The ends are sewn into bits of embroidered flannel. Some of these shades are convex over the eyes, but I believe that these are not made in Tibet, but on the Kan-su frontier, by Chinese. The eye shades are carried suspended by the girdle in a cylindrical cotton case, which can be pulled out of a cotton case of similar material, but usually handsomely embroidered, which slides over it.
William Rockhill, Notes on the Ethnology of Tibet, 1895