Conservation around the Millennium (Hungarian National Museum, 2001)

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2. Watermark found on the paper cover

I used Herzberg reagentI 11 in each case. The reagent shows diverse colour reactions when dropped on the samples. In this case, the fibres became brownish red in all the three instances. It means that the boards were composed of cotton, flax and hemp.

The determination of the grinding of the fibres was enabled by the microscopic image in a magnification of 120x. This gave the following result: all three samples were fast shredded as suggested by the slightly shredded (cut) long and short fibres.

I found a watermark on the inner cover paper of the bottom of the case (Picture 2).

Measurement of the pH of the paper

I carried out the analysis on the covering papers, and each a strip of paper from the top and the bottom boards and the wall of the lid with the help of a pH meter using combined glass electrodes.

Data measured on the lid of the case:

Data measured on the bottom of the case:- covering paper

5.4 pH- inner covering paper

4.9 pH- top board

5.1 pH- outer covering paper

5.3 pH- wall

5.4 pH- the bottom board

5.0 pH

Analysis of the glues

I took samples from the lid and the side wall of the case. The protein glues were determined with biuret reaction. The small amounts of paper were put into a cooking glass and heated in distilled water until it boiled. Then I added a few drops of 2% copper-sulphate solution (CuS04*5H20) and a drop of 5% sodium- hydroxide (NaOH) solution. The lilac colour that appeared indicated in each case that glue was applied on the plates.

Analysis of the adhesives

The sample taken from the brown adhesive that binds the paper sheets was dropped by potassium-iodide iodine solution (KJ-J2)12. A bluish grey colour appeared on the fibres, which implies the presence of starch. The colour suggests that the adhesive was not pure starch but gluten made from rye flour.13

Analysis of the adhesive used on the leather cover

The sample was put on a glass mount and potassium-iodide was dropped on it. A bluish-grey colour reaction appeared, which means that starch (gluten) was used for gluing the leather on cover.

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