In this day-by-day diary Mitchison tells us what she saw, did and felt: and the whole forms at once what is called a "human document" of rare poignancy and dramatic interest, and a book of some historical importance. In her words: "Very few people have both money and leisure, and the will, to do this. I've got this because of my profession. I rang up V[ictor] G[ollancz] on Monday evening, and asked if he'd give me an advance on a, very hypothetical, book about it. He said he would, and I'm going on that. I couldn't have otherwise. Simply as an observer I shall be some use; it's the one thing I'm sure I can do well, though I don't think I'm a good analyser. What I should like to do is to write a full diary every day, as truthful as it can possibly be. I shall type it on both sides of the sheet, so that it will fold small, and shall try and leave a duplicate with somebody; if I get my copy through, they can destroy theirs. But perhaps the whole thing is moonshine; perhaps there won't be anything to write down! If so, looking back on this afternoon from whenever it is in the future, I shall see myself looking a perfect fool. However, that won't be the first time ! Anyway, for what it's worth. I feel all thrilled now, screwed up like a child going to play Indians. Perhaps I shall be more grown-up by the end of it."