Csapodi, Csaba: Conservation of the Manuscript and Old Book Collections at the Library of the Hungarian Academy of Sciences. Methods and Results. 1949–1964 (A MTAK kiadványai 44. Budapest, 1965)

they are suspect,

e should not be put into the storage rooms without the proper treatment. Since these insects are found mostly within the hard board of the binding certain insecticides (DDT) are not of help and even alcohol injections are not dependable. Thus gas is used. But if the library is not especially equipped the application of gas involves great difficulties. Also, gas cannot be used frequently and newly acquired books cannot be regularly treated by such a method. Therefore we recently adopted a much simpler, but still effective, method: the vacuum process of Gy. BAKY. A twenty-four hour vacuum tre atment is used and during this process the lack of oxygen, of atmospheric pressure, and the drying effect destroy all kinds of living creatures. The use of the vacuum box (Plate 13) does not require any special preliminary training as does the use of glas which takes a chemical engineer. It is not harmful to the surrounding and the cost of operation is hardly more than that of the electricity consumed. Thus every suspected book can be rendered harmless and every old book can be desinfected immediately after acquisition. Defence Against the Damage Caused by Humidity and Mould Second to the parasites the greatest enemy of books is humidity and the accompanying fungi. We are aware that the spores are always invisible present in the air and thus on the surface and pages of boks. Only among certain circumstances favourable for their virulence do they cause damage; these conditions are unfavourable for the books. The greatest enemy of mould is dryness, light, ventilation, i. e. everything which discourages parasites. Among normal storage conditions no mould should occur in a library, but mould spots always appear on the binding and paper (Plate 15) if the books are kept in a wet, dark, unventilated room, and especially if they become wet. In such instance we discover that all the components of the book, the fibres of the paper, size, leather used for the binding, the linen, glue and paste, the wooden board, are first class breeding grounds for the fungi. When we find live fungi, the first thing to do is to stop the cause of wetness. The books have to be removed from the contaminated place and dried without coming into contact with other books. They must be aired, ventilated; warm air has to be circulated. The already established and developed colonies of mould must be removed from the binding and pages. If these steps are taken quickly enough and if the books did not come into direct contact with water, then all traces of mould can be removed. Even if we are a little late the penetration of the fungi under the surface of the material, hence the discolouration and slow decomposition of the paper, which is difficult or impossible to remove, may start. When black, brown, green, pink and lilac spots spread over the paper removal is practically hopeless. 6 According to the Department of Zoology of the Museum of Natural History, if wood dust falls out of the wooden cover of a book upon being rapped it is likely, but not certain, to contain live creatures. Possibly in a state of rest the dust did not yet fall from the book even though the insect causing the damage died a long time ago. If,, without rapping, dust is found between the cover and flyleaf, it is a certain sign of the work of a live parasite. 12