Note on Restoration

Restoration is a palliative for the abuse to which paper is subjected, abuse--as the preceding discussion has shown--that can take many forms. The restorer is the doctor. He knows the composition and textures of papers, old and new. He is familiar with the technical basis of applying pigments or ink to paper, and he understands and respects works of art on paper.

If a picture or book is found to be damaged in any of the ways that have been described here, it should be taken to a restorer for examination. He will report on its condition and will suggest possible means of treatment. He will also be able to offer advice on how to prevent further deterioration. He may find that washing, deacidification, and sizing are sufficient remedies. If the paper is brittle or has been weakened by corrosive inks, he may recommend reinforcing it with a thin paper. He can often successfully remove water stains and foxing, so that a picture may again be viewed with pleasure. Restoration has its limitations, but a competent restorer knows them well and will take care to inform the owner of both the limits and risks involved.

The following "case history" of a restoration incorporates most of the problems with paper that have been mentioned in this guide. The restored picture, Christ on the Cross [Netherlandish, 1450-1460], possibly the largest early Flemish woodcut.^ It was printed in a light brown ink on two sheets of paper that were joined together in the middle of the picture. It was colored by hand and then mounted on a rough panel of unplaned pine 1/4 inch thick. he over-all size of the print is 33 inches by 32 inches.

When brought in for restoration the picture was badly decayed after five hundred years of exposure to atmospheric changes, gases, candle spatterings, dirt, and dust. All these factors contributed to the oxidation, changing, and obscuring of some of the colors as well as to the general decay of the paper on which the woodcut was printed and of the wooden back on which the print was mounted. It had been attacked by silverfish [Lepisma saccharina], and its entire surface was drilled with holes by woodworms. The worms had [p. 35] eaten so much of the wooden panel and frame that it was hardly more than a shell. The silverfish had eaten from the edge inward, all around, and even into the picture itself. Paper and wood expand and contract at different rates in response to varying atmospheric conditions, and extremes of temperature and humidity had caused the paper to blister or pull away from the panel in many places. These places were very brittle and would have crumbled with even a slight pressure. When the panel had cracked the paper had cracked with it. A white deposit on the surface appeared to be the remains of a protective coating, such as varnish, applied many years ago.

At first examination it was thought that the best that could be done was to remove the dirt and possibly some of the white deposits. This was attempted by careful application of alcohol on cotton swabs rolled over the surface. The picture did clean up slightly and look brighter. But there was still the matter of conservation to be considered. Spraying it with a protective coating would make its removal from the panel difficult, if such an attempt were made. It was left in the laboratory for three months while we gathered courage and ideas for a different approach. One day, after experimenting with moisture on a corner, it was found that the agglutinant would soften readily enough and the paper separate from the panel. The plan of action was laid out.

It was thought that the best material on which to mount the print was a paper as near to the original as possible, and a craftsman of handmade paper in New York was consulted. He used some heirloom linen to make all-rag paper, with deckled edges. Two pieces from the largest mold, 23 by 18 1/2 inches, were joined, as was the original, to make a single sheet. A sample of the fifteenth-century paper had been sent to the craftsman to match for color and texture.

The picture was then photographed in black and white and in color. A scale drawing was made on a heavy board, with the help of a colored slide thrown on a screen. This was done so that, after removal from the panel, the pieces could be returned to their proper position. It was necessary to remove the entire picture from the panel before mounting it on the linen rag paper, because repeated moistening would have varied the amount of stain removed and reproduced a very uneven look when dried. An outline drawing was made on the linen all-rag paper that was to be the final backing for the picture. Since this handmade paper was fairly soft, it was dipped in sizing made from vellum and while still damp brushed over with mounting-paste made from triple-milled wheat flour.

The operation of removing the picture from the wooden panel was then started. First the panel was placed on a tilted table. Warm water was flowed [p. 38] over the fade of the print and left for five minutes. The very delicate work of removing the pieces of paper from the panel to the scale drawing was undertaken. We began with the upper left corner and worked across the top to the right and down to the center where the two pieces were joined together horizontally. This top section came off in about five large pieces. The bottom, which was in a worse state of deterioration, was much more difficult and came off in many, many pieces. The center portion of the Apostle John's robe was in particularly poor condition. St. John's raised right hand was completely eaten away by silverfish. It does not show in the before-restoration photograph because the printed outlines of the fingers were furrowed through to the wooden back.

After the pieces had been removed, they were found to be covered on the back with a thick mucilaginous substance that had been the mountant, and even small splinters from the pine panel were sometimes embedded in it. Each piece, therefore, had to be cleaned before it could be remounted. In the process of cleaning, the pieces were floated in water and placed on a blotter. The slight pressure used in cleaning the back actually caused some of the surface dirt and stain to come off on the blotter. A certain latitude in manipulation is allowed with old watercolor, because over a number of years of softening and hardening, of expanding and contracting with atmospheric changes, the pigment becomes fixed with the size and cellulose of the paper, so that warm water is not likely to move it.

When the pieces were completely removed from the wooden panel and cleaned, they were mounted one by one to the already prepared linen paper, which was to be the permanent back. With the heavy absorption of water the old paper had expanded, and even with the help of the outline drawing, a great deal of judgment was needed in arranging the pieces. Here the scale drawing proved its value. The entire procedure of removing the woodcut from the wooden panel to mounting it to a new back took two people eight hours. After a week of drying under a stack of blotter, changed several times, the reassembled woodcut was finally put for five minutes under infrared lamps, to assure complete drying. In a few places, where the original paper was missing, touches of color were added to pull the design together. After this, the picture was sprayed with a plastic [poly-vinyl-copolymer] to protect the colors and seal the paper. The restoration and treatment with plastic should prevent further decay and discoloration.

The restoration of this woodcut illustrates that even pictures that are on the brink of total disintegration can sometimes be rescued and preserved by the restorer. But it should also be a reminder that much of the damage that [p. 39] occurs to pictures can be avoided by observing the preventive measures outlined in this guide. If in providing the reader with this set of commonsense rules for preservation the authors enable him to prolong the life of at least one of his treasured pictures or books, their goal will be achieved. [p. 40]