attainable by the introduction of the lustre tints. The yellow has a full rich golden tone, and the ruby a pure vivid red. Passeri states that Giorgio brought the secret of the ruby lustre with him from Pavia, and M. Jacquemart infers that he must have produced works at Pavia before going to Gubbio; but we are inclined to think with Mr. Robinson that it was from an artist previously working at Gubbio that he acquired the art and the monopoly of the ruby tint; and it is by no means improbable that this artist, or his predecessor, may have emigrated from Pesaro as stated above. The following conclusions arrived at by Mr. Robinson after the careful study of a vast number of examples of the Gubbio and other works are endorsed by the writer, who, having contributed some few of the facts upon which those conclusions were based, has himself examined the contents of the principal European collections. Those conclusions are:-- 1st. That maestro Giorgio did not invent the ruby lustre, but succeeded to and monopolized the use of a pigment, used by an earlier artist of Gubbio. 2d. That the signed works were really painted by several distinct hands. 3d. That his own work may be distinguished with approximate certainty. 4th. That probably nearly all the “istoriati” pieces (1530-50) of Urbino, Castel Durante, or other fabriques, enriched with lustre, were so decorated by a subsequent operation at the Giorgio botega; and, 5th. Consequently, the use of lustre colours was mainly confined to Gubbio, where painted wares by Xanto and other artists working at Urbino and other places, were sent to be lustred. Before entering upon the subject of maestro Giorgio’s own works it will be necessary to glance at the earlier productions of his predecessors and probable instructors. In the absence of more positive evidence of the manufacture of early lustred wares at Pesaro, and with a view to keeping all the lustred wares together as much as possible, we have thought it more convenient to include in the large catalogue those pieces which may probably have been made at that city among the lustred wares of Gubbio, always affixing to each such piece the name of Pesaro and of Gubbio with a (?), and arranging them as a separate class. And in order to facilitate the methodical study of the rise and development of the art at Gubbio we have classified the lustred wares in the following manner, and in probable sequence of date:-- A. Works ascribed to Pesaro (or Gubbio?), the typical “bacili” referred to by Passeri, &c. B. Works believed of the early master who preceded Mº Giorgio at Gubbio. C. Works ascribed to maestro Giorgio’s own hand. D. Works of the fabrique, and pieces painted by unknown artists, though bearing the initials of the master. E. Works by the artist signing N. and by his assistants.