Cotmania. Vol. XI. 1935-6

THE COTMAN WATER-COLOURS
Times 19.9.36
WORK OF CONSERVATION
FROM OUR ART CRITIC
For some time there have been rumours in the art world about the famous collection of water-colours by John Sell Cotman and John Crome belonging to Mr. Russell J. Colman, at Crown Point, Norwich. With an invitation by Mr. Colman to a few art critics and other interested persons to view his collection the little mystery is now explained.
The collection, formed by Mr. Colman and his father with the wise object of concentrating at Norwich the pick of the Norwich School painting, consists of about 120 water-colours by Cotman, to which eight more have now been added in a manner to be described, and 13 by Crome. About two years ago it was observed that several of these precious drawings showed signs of mould growth - a subject investigated 15 years ago by Dr. Alexander Scott - and physical break-down, and further examination showed that the condition was general, all the drawings suffered in one way or another from fungus, iron mould, or "miasma." With great courage Mr. Colman entrusted the drawings to Mr. Kennedy North for cure and conservation.
Mr North's work on tempera and oil films is well known, and has been described in the Timesin connexion with the Bridgewater House Titians, the Manet "bar", and Renoir "Loge," belonging to Mr Courtauld, and the Mantegnas at Hampton Court, but this is the first time that he or anybody else has tackled on an extensive scale the more delicate problem of that water colour stain on paper. Research showed that one of the chief causes of the state of the drawings was the mounting of them with glue, pastes and other substances which form ideal culture grounds for infective and noxious growths. The problem, then, was to conserve the stain of the colour, which represented the actual work of the artist, and substitute sterile for infected, or "aseptic" for "septic," materials in the supports of the drawings.
It was first of all necessary to invent a mounting board which should be free of all animal substances and made of the most stable materials possible to obtain. The drawings were then entirely removes from whatever papers or boards they had been fastened to and attached to the new "aseptic" boards without the use of glue, pastes or any other fermenting substances. In a very few cases a paste was necessary, and after considerable research a sterile adhesive was produced by Dr. Corran in the laboratories of Messrs. J. and J. Colman of Norwich.

A RECENT DISCOVERY
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