Scientific Examination and Restoration Work

Radiographic examination of the canvas (rx7374)shows that it has been modified on several occasions. It seems important to compare the images produced by the Laboratory of the Museums of France with Robaut's notes, which contain mention of all these changes: "In November 1871, it measured only 54 by 40 ½ instead of 62 by 50. The canvas had been more or less butchered. I returned it to its original condition on the advice of the Master himself, extremely angry at seeing it to have been so ill-used. He promised me that it would be lined and enlarged to 62 by 50 format. A false signature had been added on the left. In rearranging the picture, the Master added the little sitting figure...and introduced the whole of the large shadow in the foreground". However, the artist did not appreciate the "photographic postcard" effect since it was no more than "a picture of the towers without the atmosphere of Chartres".

The edges of the original canvas, which is very fine and tightly woven (24 by 27 threads to the square centimetre), and which had been folded over to fit a smaller stretcher, were flattened out to give an enlargement of three centimetres, leaving visible traces where the canvas had formerly been tacked down. The picture has been enlarged in its lower portion by the addition of approximately 3.5 centimetres of an even more tightly woven canvas (23 by 30 threads to square centimetre) as is shown by side lit photography (10171) Narrower strips of additional canvas (approximately 2 centimetres) are to be found at the sides. These changes, which date from the lifetime of Corot, are very apparent in ultraviolet light (10172 ).

The lining done at that time was probably the work of Kiewert. The dealer's seal can be seen on the reverse of the canvas: "Paintings, water-colours, drawings, framing a speciality, Beugniet, 10 rue Laffitte - Paris "
Examination using ultraviolet photography and infrared photography confirms all these changes to the picture, but the dimensions of the canvas do not concord with the figures given by Robaut.

The various different states of the painting in 1830 and after 1871, seen in relation to the above anecdote, are not easy to discern in the X-ray. The figure standing on the right may have been added later since much broader brushwork, no longer visible at surface level traces the lines of the rock on which it is leaning. The appearance of this figure is very different from that of the young boy sitting on the left, who is not apparent in the X-ray; only the single brushstroke of his sleeve comes out clearly. Without Robaut's notes we would never have thought that this figure could be a late addition.
Radiography (rx7374) and infrared reflectography highlight the very geometric shapes formed by the structure of the Cathedral and suggest that the line of the left spire has been very slightly straightened.