Page:A Brief Outline of the Histories of Libraries.djvu/104

98 thing, in letter Moral letters to Lucilius/Letter 86, on baths, where he says, "Unless the arch is covered with glass." On this point consult my work on the baths of the Romans.

That it was also used on the walls, Vopiscus, as well as Boethius, shows when he says in speaking of Firmus, "The house appears to have been covered over with squares of glass, with bitumen and other material between the squares." I think the bitumen was here used to fasten the squares of glass to the wall, and not to join them to each other. The joints between the pieces of glass were more appropriately covered with ivory, as Boethius seems to say they were. Ivory was placed also