Cesare Cesariano, an architect, painter and writer on art, made a reference to a light and shadow device which curiously has never been adequately explained. Cesariano was born in Milan in 1483 and died there on March 30, 1543. In 1528 he became architect to Carlo V and in 1533 architect to the city of Milan. In 1521 he designed the beautiful cathedral of Como. While at Como, Cesariano prepared a translation and commentary on the _Architectura_ of Vitruvius, architect to Emperor Augustus, whose classic on the subject was rediscovered in the 15th century. Vitruvius’ book included a chapter on “Acoustic Properties of a Theatre”--a good subject for study even today. Cesariano’s edition was published at Como in 1521 with a note saying that after the sudden departure of the translator and commentator from Como the work was finished by Bruono Mariro and Benedetto Giovio. It was considered a marvelous work, to be in the vernacular and not in Latin. At this period people wanted to have books in their own language and not in Latin. While commenting on the word, _spectaculum_, translated as a “sighting tube”, Cesariano described how a Benedictine monk and architect, Don Papnutio or Panuce, made a little sighting tube and fitted it into a small hole made for the purpose in a door. It was so arranged that no light could enter the room except through the small tube. The result was that outside objects were seen, with their own colors, in what really was a natural camera system. Of course, the images were upside down, as in any camera, without a special lens arrangement, but this fact was not noted by Cesariano. The whole matter is perplexing. What is described is a “dark room” camera which, as has been observed, was never actually invented or discovered and was known for centuries. This Benedictine monk and architect may have made some refinements by carefully fitting the small opening to admit the light but that is all. At about this time, or a little earlier, the principles of the camera were set down by Leonardo da Vinci. The writer and other researchers have not been able to discover any trace of Benedettano Don Papnutio or Panuce. He certainly did not write any books or his name would be known to history and it would be possible to find more information about him and his work. There is no record of him in the Benedictine bibliography. Guillaume Libri, Italian writer, who worked in Paris in the 19th century and, incidentally, was charged with stealing da Vinci’s manuscripts, said, “I have not so far been able to ascertain who Don Panuce was, or when he lived.” Libri asserted that at any rate Leonardo’s observation of the _camera obscura_ must have been made before Cesariano saw or heard about this monk. However, Cesariano seems to have the record for the first published account of how to make a workable _camera obscura_.