Fred Francisco talks about the treatment of Colonel William Light's plan........ Click on the highlighted questions to hear the audio.

The plan pre-treatment

Conservation treatment of Colonel William Light's plan of Adelaide circa February 1837 - January-June 2003

Why did the plan need conservation?

The plan was very brittle and biscuit-like. It was also difficult to read due to discolored varnish and dirt. The brittleness was due to acids in the paper and in the glue used to attach a cloth backing to the paper base, and to the extremely thick layer of varnish over the surface of the plan. The layer of varnish was so thick that the plan could hardly be seen under the yellow gloss. The varnish obviously needed to be removed.

• What were some of the aspects of the plan and its condition when you received it, that made it problematic as a treatment....?

A preliminary conservation review of the plan indicated that any treatment would take many hours. The sheer size of the plan (approximately 1.2mX1.6m..!) was a major determining factor in how the treatment would be approached and the number of hours required. Most of the labour component was required to undo earlier – perhaps misguided – efforts to protect the plan.

• What basic things could the custodians of the plan have done in its early life to preserve and protect it better...?

A note on the back of the cloth lining on the plan indicated that in 1912 the Department of Lands had the plan "re-formed and re-varnished". This suggests that a treatment was used to reform a damaged varnish layer and that then further varnish was added – this would be consistent with the thickness of varnish the conservators encountered and with the fact that the varnish layer contained dirt.

It is not clear whether the plan was cut down, backed with cloth and nailed to a wooden stretcher 2 to 3 cms smaller in size than the plan itself, at this time. When the plan was trimmed, some road names and location markers were cut off in the trimming down and later reglued to the edges of the plan. They then reframed and glazed the plan.

The mounting system – on cloth backing and attached to a stretcher – left the plan vulnerable to damage as it was not supported adequately. The flexing of the cloth-lined paper allowed the paper to crease and fracture and probably exacerbated previous damage. As the frame had no backboard, there was nothing to prevent the cloth at the back of the plan from getting very dirty.

As the plan was framed it was likely that it was displayed, thus light damage could be another factor that contributed to its condition.

Summary of the treatment process

In order to retrieve, reveal and stabilise the original plan and the original watercolour from under the varnish, Artlab's treatment had to

1) remove the frame, the timber base and the cloth backing

2) remove the dammar varnish so that the plan could be seen

3) replace the backing with acid-free materials to provide support

4) hinge the plan to an acid-free FomecorTM base attached to a new timber frame

5 ) house the plan in a sealed PerspexTM box.

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