Name a French soldier and military engineer whose shorthand diary gave a detailed account of Napoleon'’s life

Question

Name a French soldier and military engineer whose shorthand diary gave a detailed account of Napoleon'’s life in exile.

Answer 1

Perhaps this gentleman?

"Henri-Gratien, Comte Bertrand

(Count) born March 28, 1773, Châteauroux, Fr.
died Jan. 31, 1844, Châteauroux

French military engineer and general, friend of Napoleon I and his companion in exile, first at Elba (1814–15), then at St. Helena (1815–21). His diary is considered invaluable for its frank account of Napoleon's character and life in exile. It was decoded, annotated, and published by P. Fleuriot de Langle as Cahiers de Sainte-Hélène, 1816–21, 3 vol. (1949–59, “Notebooks from St. Helena”)."

And it was in "shorthand" - see second link.

Bertrand, Henri Gratien, comte (Count)

(1773-1844)

"French soldier and military engineer, one of Napoleon's generals, born in Châteauroux, C France. Aide-de-camp to the emperor from 1804, he shared the emperor's banishment to both Elba and St Helena. After Napoleon's death he returned to France, where he was appointed commandant of the Polytechnic School (1830). His shorthand diary gave a detailed account of Napoleon's life in exile. "