Lichtgedanken 02

S C HW E R P U N K T 28 the last time the book was repaired, he says. Nobody knows now where the volume originally came from or how it ended up in the ThULB. Separated into separate folios, the da- maged paper is now ready to be repai- red by bonding fibres. »We can repair small areas by hand,« Annett Blumen- thal explains. But that would be much too complicated for large-scale damage such as on this Luther book. It is quicker to repair the holes mechanically. Mechanized papermaking The fibre bonding unit is basically no more than a bath measuring almost two square metres with a sieve in the midd- le. By raising and lowering the water level, large-format sheets of paper can be »made«. Or, as Frank Schieferdecker explains, new fibres can be added to da- maged sheets. »For this we use cellulose fibres which most closely approximate to the colour tone of the original.« In the present case, the restorer chooses a slightly brownish fibre. Practised in the art, Schieferdecker counts the quantity needed to fill the gaps in the original by hand. The cellulose is then mixed with water in a large blender and chopped up into small pieces. In the meantime, Annett Blumenthal has carefully laid the damaged sheets on the sieve in the fibre bonding bath. She adds the pulp from the blender and starts a pump. With a deafening roar, the water now rushes through a rubber hose with a sprinkler head at the end of it, and fills the bath, in the process of which the paper fibres spread finely over the whole bath. The noise is reminiscent of a laundrette when three washing ma- chines drain simultaneously. About one minute later, the bath is full. Switch off. Silence. I try to imagine how at this moment the fine fibres snuggle up to the centu- ries-old paper sheet and fill up every hole, however tiny. There is nothing to be seen of the process in the milky, cloudy liquid. A few moments later, the excess pulp is siphoned off, and Annett Blumenthal takes the sheets of the book out – now free of holes again and with a frame of new paper – and lays them on a vacuum table, still gleaming moistly. Another switch is pressed. If the noise before was like a washing machine, it now reminds you of the loud blast of air from a hairdryer. Air is now sucked Before restoration: The title sheet of the anthology of Martin Luther’s sermons from 1523 is showing major signs of damage. The holes in the paper have now been repaired and the book has been returned freshly stitched to the ThULB’s special storeroom.