Valencia," Barcelona, mentions the existence from a very early period of glass works at Olleria, a village of the kingdom of Valencia. The only mention which I have found in which Seville appears as a centre of this industry, is an interesting allusion to the village of Cala, which was represented in a festival which was given to Philip II. in 1578, "with a crystal glass in its hand, and several others at its feet, because a famous glass oven existed there." ["Recibimiento que hizo Sevilla al Rey Don Phelipe." Por Juan de Mallara, Sevilla, 1570, p. 89.] In the 17th century, during the reign of Philip IV., the glass made at Valdemaqueda in the province of Avila was very celebrated. In a royal schedule, dated 1680, which states the price at which things were sold at Madrid, "the glass made at Barcelona, Valdemaqueda, and Villafranca" are mentioned. We find the glass of Valdemaqueda was sold for a higher price than that made at the other localities. The principal value of these extracts is to prove that the industry of glass-making existed in these localities; none of the authors mentions the principal characteristics by which the vessels made may be classified. Those made at Almeria and Barcelona are more easily known, for they have kept until very recently their general character; while at Cadalso and other localities of the centre of Spain, the tradition of the Italian models has quite disappeared. In one fact every author agrees, namely, that the glass made in those provinces closely resembled the Venetian, and was completely different to the system followed by the Arabs. It is, therefore, highly probable, as I have already stated, that a large number of objects of glass of different kinds, which have been hitherto considered Italian, were made in Spain. [Illustration: VASE OF GREEN GLASS, WITH BLACK HANDLES AND RIBS.--SPANISH, 17TH CENTURY.] The following observations may serve as a guide in the difficult task of classifying this group. The specimens of glass vessels most generally met with in the neighbourhood of Cadalso are:-- Objects of white transparent glass, sweetmeat dishes ornamented with ribs, buttons, and reticulated rims with touches of gold. Objects of clear greenish glass of a paler hue than is made in the province of Almeria, decorated with blue, or some opaque colour (see woodcut); in some instances part of the object is decorated with a rough crackled surface. Objects of opaque glass with different colours, vases, glasses, cups and saucers, of thin milk-white texture with blue spots, or imitations in the Japanese style of different colours. Vases for holding flowers, and other objects, of dark blue glass, milk-white cups, glass and other objects ornamented with lines of red or blue of a thicker paste than the preceding ones.