They are not only papers, old pictures, books, notebooks or civil acts. They are the living memory of our past. A firm step into our family history, into a community or a nation's history. The true knowledge of facts, and the possibility of re-writing events over solid bases. A sacred patrimony of the people and of every family. A permanent legacy for the future.
Preservation and conservation of old documents requires specific knowledge. In some countries a carrier, in others an inherited professional discipline, it's a constant struggle against the pass of time to avoid erosions, weakness of materials and losses.
MOST OF THE FAMILIES HAVE OLD DOCUMENTS STORED IN SOME PLACE IN THE HOUSE . IN GENERAL, AND BY DIFFERENT REASONS, THEY WERE NOT PRESERVED IN THE BEST CONDITIONS.
WHY OLD DOCUMENTS DETERIORATE?
As much in the familiar household as in the libraries, museums or public archive institutions, the reason of erosion is always almost the same. It's the systematic action of light, temperature and humidity, on the chemical composition of paper, as soon as the growing of fungus and bacteria. Up to 1850, papers were made with vegetal fibers, specially cotton and linen rags. At that age, the paper had a relatively expensive cost. When this material started to run out of resources, new forms of production were invented, and a new production of paper from wood pulp (cellulose, a residual fiber from the wood of the trees) was developed. As with the new system costs decreased, the paper was cheaper than before, and magazines of great tirage showed up, initially called "pulps". For the treatment of wood pulp were started to use in 1870, some acids like the sulphuric acid and calcium bisulphate. For the bleaching compounds, chlorate acids were also used. Fibers made of cellulose chains degrade when exposed to an acidic environment in the presence of moisture, light and temperature, creating undesirable chemical reactions on the paper, like to turn it yellow, and degradation and biological effects as the apparition of fungus, bacteria and bugs infestation.
WHICH IS THE BEST WAY TO PRESERVE DOCUMENTS?
60 or 70% OF OLD DOCUMENTS WERE STORED FOR YEARS IN A BASEMENT OR IN AN ATTIC. THESE ARE THE WORST PLACES TO PRESERVE THEM.
Moreover, conditions of temperature and humidity of our grandparents' houses were not the same as today . With no air conditioning, the hot was reduced with fans, the humidity had all the possible variations, and documents and photographs had to survive as they could for a long time.
The best conditions for conservation are a neat environment, free of dust, with controlled light, humidity and temperature.
HUMIDITY: It's a very important factor. An excess of humidity creates fungus and produces a proliferation of corrosive insects. The lack of humidity, on the other hand, produces brittle and fragile sheets of paper. A controlled humidity between 30% and 40% is the best standard for preservation. With the less possible variation, and the maximum of stability, because variations of humidity provoke more damages than a stable low or medium range.
TEMPERATURE:The lower is the temperature, the better is for preservation. To make a comfortable standard for human beings in public places, a range between 65 and 68 degrees is appropriate. However, images, in general, will be better preserved at 55 degrees.
THE MOST DANGEROUS LIGHT IS THE ULTRAVIOLET FROM THE SUNLIGHT
FLUORESCENT AND HALOGEN LIGHT SHOULD BE ALSO AVOIDED.
Light has a considerable impact on document's preservation. Not only the visible light to the human eye, but the infrared or ultraviolet radiation, could cause damages. Measured in lumens/m2, 50 lux per day is the adequate amount of light for preservation. At the environments exposed to the daylight, should be installed curtains with UV filters. Documents exposed to more luminance, should be stored in dark places until its public exposition.
The AIC Code of Ethics and Guidelines for Practice, establishes that professional conservation "shall strive to attain the highest possible standards in all aspects of conservation, including, but not limited to, preventive conservation, examination, documentation, treatment, research, and education". A "rule of reversibility" indicates that any procedure must be reversible without causing damages to the documents. For example, lamination is an irreversible procedure.
PRESERVATION STANDARDS AT HOME:
Old documents never must be stored in an attic or in a basement. Regular conditions in these kind of places lead to documents' damages.
Documents must not be laminated, because this is an irreversible process, and as we have seen above, it attempts against the principles of preservation.
Documents can be bound, provided that it is done with acid-free covers. Binding helps preservation; these kind of covers can be found at bookstores or computer stores.
Plastic covers can be used to protect documents, but only those made of polyester, polypropylene or polyethylene. PVC (polyvinyl chloride) is dangerous, because it produces permanent emissions of hydrochloric acid.
When documents are stored separately between papers, it's important to verify that those separators are acid-free papers, to avoid the migration of acids between documents. Metallic clips never must be attached!
The rolled papers must be unwrapped carefully, leaving them some hours in an environment with high humidity, to make them more flexible in the moment they are unwrapped, and to avoid an easily cracking.
Old family photos should be stored in plastic protectors with pockets, taking care that they are made of acid-free components. Magnetic sheets should be avoided; they have a very high acidic emission and are very dangerous. They can, as the old papers, be stored in polyester plastic covers.
PAPERS AND PHOTOGRAPHS
To properly understand all the factors that influence on deterioration, will see separately papers and photographs.
Papyrus was used until the eleventh century, and after that age, it disappeared. The word "paper" comes from "papyrus". They are fragile, and very sensitive to humidity. Papyrus were written by only one side of the sheet, the recto (obverse).
They were used since the Pharaoh's age, at the Ancient Egypt. They were made from the stems of papyrus plants (cyperus papyrus), an aquatic plant from the Delta Nile of Egypt. It was either abundant in Sicily, Ethiopia and Syria. The strips had to be soaked and cut in thin layers, being pressed with a roller; later crossing the horizontal and vertical layers and pressed back again; the sap of the plant worked as a glue to stick the stripes together. In this way, it finally had a recto, used for the scripture, and a verso, which was not used. Very well conserved papyri were found into Egyptian tombs, due to the proper temperature and the good ventilation they had; but too bad conserved, full of fungus and insects, in churches or temples' basements. Papyrus was usually conserved rolled in wooden cylinders.
A papyrus should be conserved wrapped into linen or wool fabrics, in a place under low temperature, few humidity, stable conditions and in dark places.
Parchment is a material of biologic constitution, made from different animals' skins (goats, sheeps, calfs). It was already produced 1,500 years B.C., but its ample diffusion and its name comes from the industry developed few centuries before the Christian Age at the city of Pergamon, in Asia Minor, where actually is Turkey. Pergamon had a great library, which rivaled the Library of Alexandria.
Being much more durable and resistant than papyrus, it was, however, much more expensive. To write a book of 400 pages in large format, (56 cm x 40 cm.) at least 200 animals should be sacrificed. This was the reason for the parchment was only used for brief texts or very important writings.
It's a very hygroscopic material (absorbs moisture from the air). But at the same time it's very alkaline, with a very low value of acidity, and it makes it to be protected from fungus and moisture. Stored under high humidity conditions, causes that proteins and organic materials decompose and become gelatinised. Under low humidity, it becomes dry, showing splits and getting fragile. The ideal condition is a humidity below 50%. They tend to become of a dark yellowish color.
Parchments can be written on both sides of the sheet. Since the 8th century, they were scrubbed and scoured for rewriting. This kind of manuscripts are the palimpsests.
Animal skins were soaked in a solution with lime (that's why it's alkaline) to eliminate the rests of hair and flesh, and was tensioned in frames; later it was grazed with pumice until it was smooth in both faces. If the skin was taken from an old animal, it was used to make drums or tambourines. But coming from a young animal, a calfskin, it was called vellum, and it was used for writing.
At the Roman Empire parchments started to be grouped in membranes cut and sewn by the edges, which were called quaterniones (notebooks), and covered by boards, the codex. These books, which gave origin to the current books, were called codex membranei.
The use of parchments at the Middle Age was very reduced and limited -because of its high cost- to few important works and brief writings; everything was written tightly, with no paragraph separations and no periods, and almost without margins, to save as much space as it was possible, and with a lot of abbreviations.
Parchments must be conserved wrapped into fabrics of linen or cotton, to get them free of parasites. By their biological constitution they are very attractive for the paper-eating insects. These bugs show up when fungus or mould are present, which are also their favorite food. They must be kept in the darkness, far from the sunlight, with a humidity between 20% and 30% as maximum. To get them rid of fungus and parasites, they have to be in contact with a piece of paper with fungicide. They could also be cleaned with a sponge soaked in a 10% solution of alcohol in water, and dried immediately. If sheets become fragile and cracking they could be soften with a solution of urea dissolved at a 10% in ethanol. It's preferable that these procedures would be done by an expert, and not at home.
PAPERS MADE OF LINEN AND COTTON .-
In 1456 Johannes Gütenberg could print an entire book, The Bible, in its version of The Vulgate, with his new invention: the movable type printing. This success led to the need of making less expensive paper to supply the huge demand of printed books. Papyrus or parchments would never be able to support a high volume of demand.
From the second century China already produced paper from silk, rice and hemp, but during centuries they were the only ones making it. Near the 7th century the Arabs adopted the procedure, and when they conquered all Southern Europe, at the10th century, they introduced it in Spain and Sicile. At the 12th century in Montpellier, France, they started to install mills for the production of paper from linen fibers.
The paper was made in mills from clothes of cotton or linen, cut, washed, bleached with chloride solutions and macerated until get rid of fibers and a homogenized pulp could be obtained.
The invention of printing matched with the growing use of shirts, at the 15th century, which provided a lot of cotton clothes for the production. On the 15th century the parchment was definitely replaced by the paper.
Until that moment the paper was handmade. At the end of the 18th century in Essones, France, was invented and installed the first continuous paper making machine, with a system of rolls. The fibers of this paper followed the direction of the rolls' rotation. The mechanization of the process transformed the world: more newspapers appeared, more books were published and the activity of post mails was increased.
This kind of paper is more durable and stable than parchments. It's also a very good quality paper, alkaline, few acid. However, as it was bleached with chlorine, the acids from the composition attract fungus and undesirable microorganisms. It tends to become yellowish or of dark ocher tonalities. It's very hygroscopic. It should be conserved under conditions of low temperature, reduced and stable humidity, dark, and very neat environments, free of dust and impurities. Until the half of the nineteenth century this was the kind of paper used for all civil documents. In spite of being cheaper than parchments, however, the cost of papermaking and its price were not suitable for huge massive tirages. Paper was still expensive, and writings were done with many abbreviations and very compressed texts.
PAPER FROM CELLULOSE:
At the19th century, around 1840, linen became scarce, due to agricultural problems, which led to search new forms of production. In 1844, inventors Keller, from Germany and Fenner, from Canada, invented a new machine developing the process of papermaking from pulping wood obtained from the trees, the cellulose. The cellulose is a fiber residue of the trees.
This process was based in the removal from the pulping wood of all the wastes of lignin and the fibres, and in to process mechanically or chemically the pulp until being pressed in thin sheets and a posterior drying. In 1867 sulphuric acid for pulp's treatment was replaced by calcium bisulphate. Initially the bleach was made with sodium hypochlorite, later with chlorine dioxide and other components, like hydrogen peroxide.
At 1900 the production was improved with the Kraft process, which considerably decreased the cost of paper, resulting in a huge tirage of newspapers and magazines, called "pulps" at that time. Also the whole ecological system of the planet was engaged because of forests devastation and the indiscriminate felling of trees. The paper industry, at the 20th century, grew up due to the boom of editorial and news agencies.
The presence of all those acids in papermaking resulted in that, -since the second half of the 20th century-, we have less stable papers, more exposed to chemical degradations, and less permanents, which means, retaining very little of their initial characteristics. An acid process of papermaking is incompatible with the permanence of the product. In consequence, due to the major degradation, the care of conservation should be more straight.The acid paper becomes yellowish, creating chemical reactions transferred to other papers in contact with it. Presence of grease from hands or finger oils accelerates those reactions, which finally produces fungus, mild and infestation of bibliophage insects. These papers must be conserved in acid free supports, and into environments with stable and controlled temperature and humidity.
A very important part of the genealogical history is supported on this kind of papers.