FROM THE LOWER NILE.
Text By Brian Darnton (G.B.).
Photomicrographs by Jan Parmentier (N.L)
Experiments with the recently available material
from the exhibition shops.
At Dorchester and no doubt other towns, little exhibitions have been set up to explain the nature of ancient Egyptian culture. School children seem to flock to them and they are the subject of educational visits. In the retail areas, paintings on recently produced papyrus are for sale and kits are available to the enthusiast at very reasonable prices. Whole A5 sheets of papyrus paper are for sale at £0.50 each.
Through the use of polarising filters, it is possible to examine materials in a different perspective. When direct light is excluded by two filters set at right angles to one another, below and above the object, then certain objects of a crystalline nature may become visible or highlighted by the emission of coloured or white light. The use of this form of illumination can be very useful in objects of a botanical nature.
Fabrication of Papyrus
Papyrus is constructed by the laying of split pith from the marsh plant Cyperus papyrus in a cross hatch manner. Investigation revealed that the fibres are not in any way woven but simply laid in neat slightly overlapping rows: a horizontal layer over a vertical one. Under the sort of pressure that can be applied with a plant press, the layers stick together as they dry out . A covering of wheat meal gum is applied, to size and secure the fibres and a surface is created that is ideal for the application of art work.
The secret to the success of the papyrus lies in the stem of the plant. During secondary thickening, the vascular bundles of monocotyledonous plants grow not in ever thicker layers around the cortical tissue, but in discrete bundles distributed throughout the diameter of the stem almost at random. When these are split during preparation, the hard conductive tissue is spread as a matrix of reinforcement throughout the fabric both vertically and horizontally.
The plant grows in the wild in waterlogged marsh situations like the Nile delta and looks like very much like an overgrown version of the house plant Cyperus alternifolius with stems that are joint-less rising up to 10ft high with an umbel of pendant leaves flowing from the top.
Preparation of the Material
Boiling water breaks down the adhesion and flowing water can be used to remove any gum. Excessive layers can be carefully peeled off. Only two layers are required one horizontal the other vertical. It's a good idea to cut out at a place where a vertical strip joins a horizontal one, revealing the simple nature of this ancient product. The strips must be dried out after wiping off excess water with a paper kitchen towel. If the papyrus is dried in the open air it will shrivel and distort so a simple botanical press and a few sheets of blotting paper can be used to prevent this. When totally dried out the strips can tied between 2 glass slides to keep them flat and fully dehydrated by immersion in isopropanol and then cleared in xylene before being cut into 1/4" squares and mounted directly into Canada balsam which can then be dried off in the usual way with gentle heat. One problem which seems to arise when drying is taking place, is that cambering of the fabric can take place and some light form of pressure is essential during the process in order to avoid this. Otherwise air bubbles are drawn into the field of view.
The slides need to be rotated in crossed polarised light after extinction has been effected, the general structure of the fabric is revealed and the mount becomes a useful addition to the cabinet. An aesthetically pleasing image is created which can be enhanced by the use of a selenite plate.
Comments to the author Brian Darnton welcomed.
Visit Brian Darnton's home pages.
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Published in the April 2000 edition of Micscape Magazine.
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