Conservation of Chinese watercolours from the Ann Lee collection

Find out how a paper conservator at Kew, Emma Le Cornu, conserved a collection of extremely fragile Chinese watercolours.

An old book open in the library

I have recently completed conservation of a large collection of botanical watercolours that were on a variety of supports including paper, vellum and a very fragile Chinese paper.

Ann Lee Collection

The Ann Lee collection contains 165 botanical illustrations. The collection is attributed to the 18th century botanical artist Ann Lee, with about two thirds of the items painted by her. The remaining approximately 60 items are Chinese in origin, painted on Chinese paper and most likely painted by Chinese artists.


botanical illustration by Ann Lee

Watercolour on vellum by Ann Lee, 1775, before treatment 

There is little information available on the provenance of the collection. It is likely that it belonged to Ann Lee’s father, James Lee, nurseryman of Hammersmith, who supplied exotic plants to Kew. The Chinese watercolours may have been collected by James Lee as examples of exotic plants. The collection was presented to Kew in 1969. 


Chinese botanical watercolour

Chinese watercolour by an unknown artist, showing insects in various stages of development: Before treatment


All 165 items were stored in one slim box in paper folders. The majority of the collection was in a fair condition but with tears and creases around the edges as a result of poor storage and handling in the past. These required minor repairs, removal of tape, cleaning of dirt on the surface and re-housing in new mounts and boxes. However, about 10% of the collection was in an extremely poor condition with the supports in fragments and extremely brittle paper that would break into pieces if touched or moved. 


Chinese botanical watercolour before treatment

Chinese watercolour by an unknown artist, before treatment. The paper is very discoloured and brittle and has broken into fragments

Due to the nature of the Chinese paper, which is very thin and weak, I contacted experts in Chinese paper conservation at the Hirayama studio in the British Museum for advice on treatment.This resulted in collaboration between Kew and the British Museum. I took two of the most damaged watercolours to the Hirayama studio where I was given training by the Chinese paper conservator, then carried out the treatments under her supervision and with her assistance. 


The watercolours were so damaged that the only treatment possible was to apply a lining to the back of the paper to hold it all in place. This was very challenging as the paper was so difficult to handle. The Chinese method was the best solution as it is very quick and does not use much moisture, which may cause the colours to run.

Chinese watercolour lined with paper

In the Hirayama studio at the British Museum, lowering the lining paper onto the back of the watercolour and brushing the back to ensure the paper is fully attached

However, it requires skill to place the lining onto the back of the watercolour in one go and there are no second chances. Two layers of Chinese paper are coated with glue, lowered onto the back of the watercolour then brushed over to make sure the papers are firmly attached. With many practice runs and with the assistance of the Chinese paper conservator, I was able to line the two watercolours successfully.

Smaller fragments needed to be fitted into place after lining. This was carried out piece by piece and fitted together like a jigsaw puzzle. See how this was done on the video below (the process has been speeded up).

Chinese watercolour conservation treatment from Emma Le Cornu on Vimeo.

Now that the watercolours are lined they can be handled safely without any risk to the paper or the image.


Chinese watercolour after treatment in mount

Chinese watercolour by an unknown artist: After treatment in a window mount

The whole collection has now been re-housed in window mounts and in archival storage boxes and is available to researchers and to go on display. 

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