In an apartment at Paris, one morning during the Reign of Terror, a man, whose age might be somewhat under thirty, sat before a table covered with papers, arranged and labelled with the methodical precision of a mind fond of order and habituated to business. Behind him rose a tall bookcase surmounted with a bust of Robespierre, and the shelves were filled chiefly with works of a scientific character, amongst which the greater number were on chemistry and medicine. There were to be seen also many rare books on alchemy, the great Italian historians, some English philosophical treatises, and a few manuscripts in Arabic.