We have already spoken of the matrix. Where silk or other thin woven materials are to be blocked, a firm hard board must be laid on the table and frequently changed, otherwise the impression will be defective. For ribbons for wreaths, &c., a suitable piece of paper which had been damped some time before should be laid underneath.

Although relief blocking upon bindings seems to be out of favor, there are numerous styles of imitation relief practiced nowadays, especially in imitation of cut leather or wrought metal. This work necessitates the matrix or table being prepared with great care, as it must be the counterpart of the plate. For this purpose an impression is first made upon a stout cardboard, which is fixed firmly enough on the bed to prevent its shifting, the block being affixed to the platen. Upon this first cardboard are laid the raised parts according to the height required, likewise cut out of stout cardboard, continuing to place a layer upon the other until a true negative of the block is obtained. Small and slightly raised ornamentation is not specially under laid using instead a piece of stout board well smeared with cobblers' wax, which, after standing awhile under the plate in the closed press, will make a very exact and firm base. Matrices made up of several layers of cardboard pasted on top of each other are also, when finished, covered with a piece of pasted packing paper and then pressed, This leaf prevents single pieces from working loose and sticking to the block.

For relief stamping, leather or cloth is stretched upon thin wrappers. The guide' points must be made a little further apart on account of the material shrinking slightly under relief stamping.

Color blocking, which has gained such unexpected popularity, gives the finisher no little trouble. As blind blocking is done by the press, so also may color blocking be done if the blocks are colored with the brilliant colors specially prepared for printing. A color roller, made by molding English roller composition on a wooden pin, is used for coloring the blocks. The worker himself may cast these rollers in a well-greased mould. The roller composition is dissolved in water, and after being poured into the mould is allowed to stand a few hours to cool. The color blocker keeps about three rollers ready, of which one is used for light colors, another for middle tones, and the third solely for black. The rollers are either fixed in a fork with two handles or an axle goes through the wooden pin which is bound in leather at each end wherein the axle revolves in the hollow of the hand.

The rollers spread the color upon a stone of suitable size. The color should be laid on the rollers not on the stone-not too thickly, and then evenly distributed on the stone by bringing the roller over it backwards and forwards. Both stone and roller must always be cleaned after use; perfect cleanliness must be carefully observed throughout. The stone is cleaned with petroleum, the remaining color is removed from the roller by passing it several times over a sheet of glass, rubbing it down with petroleum before again using it so as to remove any particle of dust adhering.

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