The influence of the ideas of Clausewitz upon the historical studies of the general staff is clearly marked. In 1862 was published "The Italian Campaign of the year 1859, compiled by the Historical Department of the General Staff of the Royal Prussian Army." It is an open secret that this work was written by Moltke himself; and therefore it is worth noting that the preface describes the object of the book almost in the words of Clausewitz: "to ascertain as accurately as possible the nature of the events in Northern Italy during those few eventful weeks, to deduce them from their causes--in short, to exercise that objective criticism without which the facts themselves do not afford effective instruction for our own benefit." The history of the Italian campaign is a model of this positive criticism. At, every stage the writer places himself in turn in the position of the commander of each side, and sketches clearly and concisely the measures which at that moment would, in his opinion, have been the most appropriate. This is undoubtedly the true method of teaching the general's art, and the best exercise in peace that can be devised for those who have acquired its mastery. In 1867 appeared "The Campaign of 1866 in Germany, compiled by the Department for Military History of the Great General Staff." This work is described in its preface as "drawn from the official reports of the Prussian troops, and intended in the first instance for their use. The description," the writer goes on to say, "is one-sided, because hitherto our late antagonists have not made disclosures such as would suffice to explain the motives of their action." A similar qualification may be applied to the account of the Franco-German war published by the great general staff. But both works supply, within the limits laid down by their authors, precisely the kind of history which is of the greatest value to the military student. The utmost pains have been taken to secure a true statement of facts, and a clear exposition of the guiding motives on the Prussian or German side. Accordingly these works, and the account published more recently of the campaign of 1864 in Denmark, form rich storehouses of material for that "objective criticism" in the exercise of which lies the principal means of maturing the military judgment.