However, some controversy has arisen over the exhibit because the so-called "biggest exhibit ever" of Da Vinci contains mostly reproductions, not originals, and attributes some of the displayed artwork to Da Vinci, although critics say they are almost certainly not his work.

James S. Ackerman '60, Kinglsey professor emeritus of fine arts at Harvard, quit his advisory position in the exhibit over objections to many of the attributions in the display.

"[One of the pieces had] a 99 percent probability of not being a Leonardo," he said in a Boston Globe article. "If even one more attribution to Leonardo were discovered, it would be front page news."

Ackerman says he is concerned that such loose attributions could be used to increase the value of pieces whose origins are less than reputable, noting that attributions from exhibit catalogues are often used to appraise the value of works.

The conflict has raised questions about the role that "non-art" museums like the Museum of Science should play in the in establishing artistic accreditation, as they have usually not dealt with valuable or well-known pieces of art.

However, the Museum of Science says the exhibit is appropriately placed because it emphasizes the scientific aspects of Da Vinci's work as opposed to the artistic.

"The art is only one third of an exhibit that tries to emphasize the scientific qualities of Leonardo," says Otto Letski, director of the cultural exchange for the exhibit, during a press preview.

"Five hundred years ago it was not interesting to sign and date your work. We did not have such a cult of personality back then."

The exhibit's expert on Leonardo da Vinci, Professor Carlo Pedretti, agrees.

"The purpose of an exhibit like this is not to publish, but to educate."

Having originated in Germany, the display has already traveled through several venues in Europe, including Sweden and Denmark. After September, the exhibit is scheduled to move east to Singapore.

The display follows a theme of Leonardo da Vinci exhibits throughout the country, following the coattails of Da Vinci's Codex Leceister, the artist's 16th-century manuscript that Bill Gates bought in 1994 for $30.8 million which is currently on display in Paris at the Musee du Luxembourg.

The manuscript has been on tour in New York, Milan and Rome since its purchase by the Microsoft chair two years ago. The document features sketches by the artist and his theories on evolution.