Books are destroyed chiefly by damp and the mould it feeds, and also by insects, rodents, sunlight, rough handling and fire, so keep them dry, in moving air, off the floor and away from outside walls, handle them with clean dry hands, and make a second copy of any that matter before they decay. A book that shows mould is handled outdoors with a mask, because the spores are a health hazard.
Protecting the printed and written material that survives a collapse, and diagnosing damage when it appears.
Water Is The Main Enemy
Paper is plant fibre, and it swells, stains and rots when wet. Mould grows on damp paper, leather and cloth bindings in still, humid air, and a book that stays damp can be ruined (how fast depends on temperature and humidity). The parent article’s advice to store in dry places, off the ground, is the single most important instruction. Add: away from outside walls and roof leaks, on shelves with air moving behind and around them, and not packed so tight that air cannot circulate.
Do not seal damp books into wrapped or closed containers. Cloth wrapping, as the parent suggests, should be breathable cloth around dry books; sealed plastic or tight tins around books that have not fully dried hold moisture in and encourage mould.
Diagnosis: What The Damage Tells You
| What you see | Likely cause | First response |
|---|---|---|
| White, grey, green or black fuzz or powder, musty smell | Mould | Move outdoors, dry, wear a mask, brush off dry mould |
| Pages stuck, wavy and stained, tide lines | Water damage | Stand upright, fan the pages and dry in moving air out of direct sun |
| Small round holes or fine tunnels, powdery dust | Wood- or paper-eating beetle larvae | Isolate from other books, inspect the shelf and its wood |
| Scraped, irregular patches on surfaces, silvery insects | Silverfish or similar | Reduce damp, clear crumbs and old paste |
| Gnawed edges, shredded paper nests | Mice or rats | Seal gaps, trap, move books up and off floors |
| Yellow-brown edges, brittle paper | Age, light, or acidic paper | Dim storage; copy the text soon |
Acidic paper is a feature of wood-pulp paper, which became common from the nineteenth century (recalled, not checked), and is far more fragile than the rag paper in older books. See Paper Making for why rag paper lasts.
Method: A Book Store That Works
Step 1: Choose the driest, coolest, darkest room, not the attic and not the cellar.
Step 2: Shelve upright, with books supported by their neighbours or a bookend, and large heavy volumes flat.
Step 3: Keep them off the floor, with an air gap behind each shelf.
Step 4: Keep a lending register and a single librarian, as the parent article advises. See Library Building.
Step 5: Inspect each season, opening a sample of books and looking for the signs above.
Step 6: Copy the vital ones before they fail and store the copy in a different building. Prioritise by use: Library & Bookstore Priorities, Redundant Copies and Redundancy: Multiple Carriers.
Handling Rules
Clean, dry hands. Open the book gently without forcing the spine flat. Do not wet a finger to turn a page. Do not mend with tape or glues of unknown type, which discolour and make later repair harder. Never leave books in sunlight.
Common Mistakes
- Storing on a floor or against an outer wall.
- Wrapping damp books.
- Keeping the only copy where the stove or lamp is. Fire destroys it in minutes.
- Lending without a register.
- Waiting until a book deteriorates before copying.
Mould spores, pests and fire
Mould spores can cause allergic reactions and breathing trouble. Handle mouldy books outdoors, wear a cloth or better mask, wash hands afterwards, and do not let children handle them. Do not use poisons or fumigants on books in rooms where people sleep or children play. Keep lamps, candles and stoves away from book stores, and store books so that no single fire takes both a book and its copy.
What’s Next
- Learn next: Knowledge We Cannot Afford to Lose
- Combine with: Book Binding for repairing and making volumes