HISTOKY OF GLASS-MAKING.

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by no means exclusively, mica, alabaster, and shells having been also used. Glass,in flat pieces, such as might be employed for windows (No. 307), has been found inthe ruins of Roman houses, both in England and Italy, and in the house of theFaun at Pompeii, a small pane in a bronze frame remains. Glass of this descriptionseems to have been cast on a stone, and is usually very uneven and full of defects;although capable of transmitting light, it must have admitted of at best an indif-ferent view of external objects. When the window openings were large, as wasthe case in basilicas and other public buildings, and even in houses, the pieces ofglass were, doubtless, fixed in pierced slabs of marble or in frames of wood. Thepieces of glass or other transparent substance so employed were, we may infer,called specula. The use of glass for this purpose appears to have been familiarto Pliny, as he says that specula were invented at Si don.* Specularii are men-tioned in the Codex (Lib. x. tit. 64), in an ordinance of Constantine II., a.d. 337.They probably were the glaziers of the time, working, however, in other materialsas well as in glass; specular bearing the meaning of window, f

In this collection is a piece of glass (No. 308), bent by heat, which was givento the writer by Canon Yon Wilmowsky, of the Cathedral of Treves; it was foundwith a large quantity of similar pieces under the walls of that church, accompaniedand overlaid by such other remains as to make it tolerably certain that they wererelics of the church, burnt in a.d. 420, when the city was pillaged by the Franks.

3.—GLASS IN EUROPE, FROM A.D. 400 UNTIL A.D. 1000.

We have very little positive knowledge of the state of the art of glass-makingat Rome, or in the provinces, during the ages which witnessed and followed thedecline and fall of the Empire; whatever vessels may have been produced by theworkshops were no doubt made by the same processes as those of earlier times, andare probably scarcely distinguishable from them, except by imperfection of manu-facture. One specimen in this collection {Fig. 72), which may belong to thisperiod, deserves notice; it is a vase, the handles of which have been lost. Asimilar example in the British Museum, which has preserved its handles, is of thesame coarse blue glass, and quite as clumsily made. It exhibits a form closelyresembling that of the cups which are frequently represented on the sepulchralmemorials of the Christians of the earlier ages, and which there is every reason tobelieve were intended to represent the chalices used in the Communion. A small

* {Hat. Hist., Lib. xxxvi, c. 26.) “ Sidone quondam liis officinis nobili, siquidem etiam specula

excogitaverat.” We cannot understand by specula, mirrors in this passage, unless we suppose thatthe art of silvering mirrors had been invented at Sidon. See Beckman’s History of Inventions, art.Mirrors. A fragment of a circular mirror of glass, foliated with a thin sheet of pure lead, is stated tohave been lately discovered in excavations at Lillebonne.

t “ In caldarium suum latis specularibus diem admiserat.” (Seneca, 1. iii. Ep. 86.)