It was not till the end of the twelfth century that any important advance was made in our narrower department of ‘hollow ware.’ Among the many beautiful things made during that glorious season of artistic production that had its start about this time in Egypt (or perhaps, rather, in the lands between the Persian Gulf and the Mediterranean)—except it be the inlaid metal work—there is nothing that now interests us so much as the enamelled glass, the beautiful ware that culminated in the magnificent Cairene mosque lamps of the thirteenth and fourteenth centuries. The art of enamelling on glass passed over to Venice in the fifteenth century, perhaps earlier, and there in the next century the manufacture of the famous _cristallo_ was finally achieved, and complete mastery was obtained in the working of this pure white glass. A fresh start was now given to the industry in the north by means of the Venetian glass-workers, who were sought for in every country to teach their new methods. In Germany alone did some of the traditions of the old forest-workers of ‘green-glass’ survive. By the end of the seventeenth century the German glass, in some respects to be regarded as a compromise between the old and new, had become the most important in Europe. For a hundred years the products of ‘the mountain fringe of Bohemia’ held the premier position, but towards the end of the eighteenth century this place was taken by the facetted flint-glass of England. It is certainly remarkable that it is only of quite recent years that any such prominent position could be claimed for France, which heretofore had been content to follow in the wake first of Venice and then of Germany and of England. At the present day, however, this at least may be said—that France is almost the only country where any really artistic work in glass, apart from the reproduction of old patterns and old methods, is being produced. This hasty sketch of the history of glass-making will help us to understand why it is that in following the development of the art in so many lands, and for a period of more than three thousand years, there is no need to linger for any time except at a few of the more important _étapes_. Indeed such a procedure is forced upon us, for much of the road is quite barren, other parts are unexplored, while for whole stages we pass through prosaic districts where we find little of artistic merit to detain us.