He begins with cosmology. Dialogo sopra i due massimi sistemi del mondo, published in Florence in 1632, is placed on the following year in the Index of forbidden books. Galileo now suspect of heresy can no longer publish his works in a Catholic country. Fortunately this ban does not stop his activity.
The treatise on physics, titled Discorsi e dimostrazioni matematiche intorno a due nuove scienze attenenti alla mecanica e i movimenti locali, is ready in 1636. The comte of Noailles transmits a copy to Elzevier who publishes the book at Leyden in 1638. The book is dedicated to Noailles.
The Discorsi includes Galileo's assertion that the distance traveled in a naturally accelerated movement is proportional to the square of time. Galileo supports this discovery by describing an experiment using a steel ball rolling in a groove. For three and a half centuries the learned world will question the possibility of such measurement with the required accuracy at the time of that demonstration. It is now taken for sure that this very real experiment, published for the first time in the Discorsi, was made by Galileo in 1604.
On April 26 in Paris (Drouot), the auction house Pierre Bergé et Associés in co-operation with Sotheby's sells the association copy of the comte de Noailles, lot 21 estimated € 700K. Some typographical errors are present but without the usual erratum, suggesting that this copy was the very first that was released from Elzevier's presses. It is assembled in a sumptuous 'à la fanfare' binding attributed to Le Gascon, certainly commissioned by Noailles.
Physics is less disruptive than astronomy for the religious authorities and the Discorsi will not be threatened. Much later Einstein would acknowledge Galileo rather than Newton as the father of modern physics and more generally of modern science.
SOLD for € 730K including premium