'It then became necessary to see the places, to study the geography of my book, for at that period I did not know where my scenes were to be laid, whether on the banks of the Rhine, or elsewhere. So, with my rough draft in my pocket, and my head teeming with the shadows of my marionettes, and of the things that they were to do and to explain, I set off for Rheims and went carefully over the whole ground, driving from Rheims to Sedan, and following foot by foot the road by which the Seventh Corps--already then decided upon as the _milieu_ in which my novel was to develop--marched to their disaster. During that drive I picked up an immense quantity of material, halting in farmhouses and peasants' cottages, and taking copious notes. Then came Sedan, and after a careful study of the place and the people, I saw that my novel must deal largely, for the full comprehension of my story, not only with the locality, but with the people of the town. This gave me the _bourgeois_ of Sedan, who play an important part in my tale. Little by little, the geography gave me also the physiology of my book. Each new place that it became necessary to describe supplied its type, its characters. 'So, on my return to Paris, I was in an immense workshop or yard surrounded with huge mountains of hewn stones, mortar and bricks, and all that remained then to do was to build the best structure that I could build of these materials. But before that, the architect's plan was necessary, and that I next carefully evolved. My plan of work is most rigorous. Each chapter is marked out in advance, but it is only as I am writing that the various incidents which I have collected fall into place.... My labour has been one of reconciliation of divergent statements in the first place, and of condensation in the second. I had to reduce to one page what I could easily, and without prolixity, have treated in a dozen pages; so that with each page, nay with each sentence, I have been confronted with the question what to leave out and what to say. Then, when each page was written, I began to torture myself with the doubt whether I had left unsaid things I ought to have said, whether I had sacrificed good to inferior material.