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...