The following extracts from this Preface describe the man and his work: Moreau de Jonnes died at the age of ninety-two, on the eve of the day on which war was declared in 1870. He was a Splendid old man, sturdy to the end, a savant, of precise observation, minutely accurate, endowed with a prodigious memory, and held indisputably the first place in statistics in France.