A 248-Year-Old Notebook Sat Misfiled in Paris. It Turned Out to Be New Mozart.

In a stack of roughly 20 anonymous manuscripts at the National Library of France, a curator named François-Pierre Goy leafed through a 44-page notebook and felt, uneasily, that he had seen this handwriting somewhere before.

He had. He'd spent weeks buried in Mozart's own manuscripts just before this, and the match was unmistakable, down to the pen strokes. The notebook was not anonymous. It had simply been waiting, misfiled, for 248 years.

The notebook was kept by the 22-year-old composer between May and July 1778, while he was staying in Paris, employed as a music tutor for Marie-Louise-Philippine de Bonnières de Guînes. Her father, the Duke of Guînes, was a celebrated flute player who had already commissioned what became Mozart's Concerto for Flute and Harp. Some pages are the student's work alone. Others show teacher and student writing side by side.

Mozart was not impressed with his student. He wrote home that she had no musical ideas and no future ones on the way. The music he composed alongside her during those lessons had never, until this year, been heard by anyone.

During the French Revolution, authorities confiscated the Duke of Guînes' music collection in 1794. It entered France's national archives and faded into obscurity. This month, audiences heard the works performed for the very first time.

The student had no ideas. The teacher had plenty. The French Revolution held them in storage for 230 years.

Read the full story at Smithsonian Magazine, June 25, 2026

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