Boule subsequently learned to economise labour by adopting a similar process to that used by the marqueterie cutter; and by glueing together two sheets of brass, or white metal, and two of shell, and placing over them his design, he was then able to pierce the four layers by one cut of the bandsaw; this gave four exact copies of the design. The same process would be repeated for the reverse side, if, as with an armoire or a large cabinet, two panels, one for each door, right and left, were required; and then, when the brass, or white metal cutting was fitted into the shell so that the joins were imperceptible, he would have two right-hand and two left-hand panels. These would be positive and negative: in the former pair the metal would represent the figured design with the shell as groundwork, and the latter would have the shell as a design, with a ground of metal. The terms positive and negative are the writer's to explain the difference, but the technical terms are "first part" and "second part," or "Boule" and "counter." The former would be selected for the best part of the cabinet; for instance, the panels of the front doors, while the latter would be used for the ends or sides. An illustration of this plan of using all four cuttings of one design, occurs in the armoire No. 1026 in the Jones Collection, and in a great many other excellent specimens. The brass, or the white metal in the design, was then carefully and most artistically engraved; and the beauty of the engraving of Boule's finest productions is a great point of excellence, giving, as it does, a character to the design, and emphasizing its details. The mounting of the furniture in ormolu, of a rich and highly-finished character, completed the design. The _Musée du Louvre_ is rich in examples of Boule's work: and there are some very good pieces in the Jones Collection, at Hertford House, and at Windsor Castle. The illustration on page 144 is the representation of an armoire, which was, undoubtedly, executed by Boule from a design by Lebrun: it is one of a pair which was sold in 1882, at the Hamilton Palace sale, by Messrs. Christie, for £12,075. Another small cabinet, in the same collection, realised £2,310. The pedestal cabinet illustrated on page 148, from the Jones Collection, is very similar to the latter, and cost Mr. Jones £3,000. When specimens, of the genuineness of which there is no doubt, are offered for sale, they are sure to realize very high prices. The armoire in the Jones Collection, already alluded to (No. 1026), of which there is an illustration, cost Mr. Jones between £4,000 and £5,000.