At the end of May he is back in Paris. He soon finds out about the tragic events in Spain: the abdication of Carlos IV in favour of Fernando VII who ends up giving power to his father and then him to Napoleon, who put his brother José I on the throne; the massive uprising against Napoleon on the second of May in Madrid, and the subsequent executions of those days, beginning the War of Independence all over Spain.
On June 20th the Gabinete de Máquinas is evacuated, the plans and models are taken to the Academia de San Fernando, because its dependencies are to be used as barracks to house the Napoleonic troops, until Madrid is liberated and they go back to the Buen Retiro in September, under the supervision of José Sureda.
At the École Polytechnique of Paris Betancourt and Lanz present their Essai sur la composition des machines. Its first edition came out this year, Betancourt already being in Russia; it was preceded by Programme du cours élémentaire des machines of Hachette, that he had taught at the Polytechnique in 1806.
Betancourt leaves again the administration of his goods in hands of Breguet before leaving in mid September for Russia with his wife and children.
In October Betancourt has another interview with the tsar Alexander I at Erfurt and on October 30th is already installed in St Petersburg with his family. He will never leave Russia again.
