Putnam, a brave officer but no general, managed things so badly in the Highlands that Forts Montgomery and Clinton were lost, and the Hudson was opened to the enemy whenever he chose to advance.[729] CRITICAL ESSAY ON THE SOURCES OF INFORMATION. THE titles alone of the numerous works which have been consulted in the preparation of the foregoing narratives would fill many of these pages. Therefore, to avoid repetition, as most of them are common to all the chapters of this History of the American Revolution, reference will be made only to those authorities which have a bearing upon disputed points, or to newly discovered facts respecting the "Struggle for the Hudson." Of the many authors who have written of the New York campaign of 1776, nearly all have followed the narrations given in Sparks's _Washington_ and in the official despatches of the various officers engaged. For topographical details we have relied upon Des Barres' _Atlantic Neptune_ (1780-81), with its plans of battles, sieges, etc., and maps of the seat of war, and upon the recent Coast Survey charts. Local historians have supplied many minor particulars, which need not be enumerated, except, perhaps, the one relating to the treason of William Demont, already referred to in the text. Much new light has been thrown upon the Burgoyne campaign by works published within the last few years.[730] One of the most earnestly disputed points of Burgoyne's campaign is whether Arnold was personally engaged with the enemy at the battle of Freeman's Farm, on Sept. 19, 1777. Some authorities, notably Bancroft, while admitting that Arnold's troops were in the thickest of the fray, deny that the general himself was on the battlefield; while Stedman, Irving, Stone, and many others, equally competent to weigh the facts, maintain that Arnold was the conquering hero of the fight, and that, but for him, Burgoyne would have marched straight on to Albany. Just after Gates had superseded Schuyler in the command of the Northern army, Arnold had returned from the Mohawk valley flushed with success and impatient to win new laurels. He was incessantly engaged in skirmishing with the enemy and adding to his reputation as a brilliant, dashing officer. Gates was envious of Arnold's growing fame, and resentful of his partiality for Schuyler. Hence arose a coolness towards Arnold, which rapidly ripened into bitter hostility. That the action of Freeman's Farm, a five hours' battle, full of skilful movements, was purely a series of chance operations without a guiding spirit, is utterly preposterous. As Gates was not engaged, whose was the directing mind but Arnold's, the second in command?