This is an excerpt of a letter from Gauss to Bessel, used with
kind permission of the Niedersächsische Staats- und
Universitätsbibliothek Göttingen. The original letter has
been photocopied, and the copy has been scanned in at 300dpi using a
grey level scanner. The data are stored in TIFF format.
The challenge is to reconstruct the original writing from the
available data. For more information, see the story
of this letter.