Fig. 16.
When a small plate or leaf has to be inserted into a larger book, it is best to “inlay it”; that is to say, the plate or leaf is let into a sheet of paper the size of the page of the book. To do this, a piece of paper as thick as the plate to be inlaid, or a little thicker, is selected, and on this is laid the plate, which should have been previously squared, and the positions of the corners marked with a folder. A point is made about an eighth of an inch inside each corner mark, and the paper within these points is cut out (see [fig. 16]). This leaves a frame of paper, the inner edges of which will slightly overlap the edges of the plate. The under edge of the plate, and the upper edge of the mount, should then be pared and pasted, and the plate laid in its place (with the corners corresponding to the folder marks). If the edges have been properly pared, the thickness where they overlap should not exceed the thickness of the frame paper. If an irregular fragment is to be inlaid, it is done in the same way, except that the entire outline is traced on the new paper with a folder, and the paper cut away, allowing one eighth of an inch inside the indented line.
FLATTENING VELLUM
The leaves of a vellum book that have become cockled from damp or other causes may be flattened by damping them, pulling them out straight, and allowing them to dry under pressure. To do this take the book to pieces, clean out any dirt there may be in the folds of the leaves, and spread out each pair of leaves as flatly as possible.
Damp some white blotting-paper by interleaving it with common white paper that has been wetted with a sponge. One sheet of wet paper to two of blotting-paper will be enough. The pile of blotting-paper and wet paper is put in the press and left for an hour or two under pressure, then taken out and the common paper removed.
The blotting-paper should now be slightly and evenly damp. To flatten the vellum the open pairs of leaves are interleaved with the slightly damp blotting-paper, and are left for an hour under the weight of a pressing-board. After this time the vellum will have become quite soft, and can with care be flattened out and lightly pressed between the blotting-paper, and left for a night. The next day the vellum leaves should be looked at to see that they lie quite flat, and the blotting-paper changed for some that is dry. The vellum must remain under pressure until it is quite dry, or it will cockle up worse than ever when exposed to the air. The blotting-paper should be changed every day or two. The length of time that vellum leaves take to dry will vary with the state of the atmosphere, and the thickness of the vellum, from one to six weeks.
Almost any manuscript or printed book on vellum can be successfully flattened in this way; miniatures should have pieces of waxed paper laid over them to prevent the chance of any of the fibres of the blotting-paper sticking. The pressure must not be great; only enough is needed to keep the vellum flat as it dries.
This process of flattening, although so simple, requires the utmost care. If the blotting-paper is used too damp, a manuscript may be ruined; and if not damp enough, the pressing will have no effect.
CHAPTER IV
Sizing—Washing—Mending