Baker's _Chronicle_ was finally edited by Professor Maunde Thompson in 1889. The work is a standard work and generally regarded as the best example of its kind. In making his notes upon that document, Professor Maunde Thompson compared the halting-places given by Baker and other authorities with those of the Accounts of the Kitchen, and established for the first time something like an exact record. But many apparent discrepancies still remained and several puzzling anomalies. I have attempted in what follows to reconstruct the whole accurately, and I think I have done so up to and including the passage of the Somme from Boismont, a point not hitherto established. First, I would point out that of all the few bases of evidence from which we can work, that of the Clerk of the Kitchen's accounts is by far the most valuable. It should be a canon in all historical work that the unconscious witness is the most trustworthy. I mean by "unconscious" evidence the evidence afforded by one who is not interested in the type of action which one is attempting to establish. Suppose, for instance, you wanted to know on exactly what day a Prime Minister of England left London for Paris upon some important mission. His biographer who sets out to write an interesting political life and to insist upon certain motives in him, will say it is the 20th of June, because Lady So-and-So mentions it in her diary, and because he finds a letter written by the Prime Minister in Paris on the 21st. Perhaps it is more important to the picturesqueness of the detail that the journey should be a hurried one, and without knowing it the biographer is biased in that direction. There may be twenty documents from the pens of people concerned with affairs of State which would lead us to _infer_ that he left London on the 20th, and perhaps only five that would lead us to infer that he left on an earlier day, and, weighing the position and responsibility of the witnesses, the biographer will decide for the twenty. But if we come across a postcard written from Calais by the Prime Minister's valet to a fellow servant at home asking for the Prime Minister's overcoat to be sent on, and if he mentions the weather which we find to correspond to the date, the 19th, and if further we have the postmark of the 19th on the postcard, then we can be absolutely certain that the majority of the fuller accounts were wrong, and that the Prime Minister crossed not on the 20th but on the 19th, for we have a converging set of independent witnesses none of whom have any reason to make the journey seem later than it was, all concerned with trivial duties, and each unconscious of the effect upon history of their evidence. It would be extraordinary if the servant had forged a date, and if we suppose him to have made a mistake, we are corrected by the equally trivial points of the postmark and the French stamp and the mention of the weather.