9. In the midst of the gloom, the country was shocked by the news that Benedict Arnold had turned traitor. After the battle of Bemis's Heights, in the fall of 1777, he had been promoted to the rank of major-general, and made commandant of Philadelphia. Here he married the daughter of a royalist, and entered upon a career of extravagance which overwhelmed him with debt. He then began a system of frauds on the commissary department of the army. Charges were preferred against him by Congress, and he was convicted by a court-martial. [Sidenote: =Treason of Benedict Arnold.=] 10. Seeming to forget this disgrace, Arnold obtained command of the fortress of West Point, on the Hudson. On the last day of July, 1780, he assumed control of the arsenal and depot of stores at that place. He then entered into a secret correspondence with Sir Henry Clinton, and finally offered to betray his country. It was agreed that the British fleet should ascend the Hudson, and that the garrison and fortress should be given up without a struggle. 11. On the 21st of September, Clinton sent Major John André to make arrangements for the surrender. André, who was adjutant-general of the British army, went ashore from the _Vulture_ about midnight, and met Arnold in a thicket. Daydawn approached, and the conspirators entered the American lines. André, disguising himself, assumed the character of a spy. [Sidenote: =Capture of Major André.=] 12. During the next day the business was completed. Arnold agreed to surrender West Point for ten thousand pounds and a commission as brigadier in the British army. André received papers containing a description of West Point, its defences, and the best method of attack. During that day an American battery drove the _Vulture_ down the river, and André was obliged to cross to the other side and return by land. He passed the American outposts in safety; but at Tarrytown he was confronted by three militiamen[B] who stripped him, found his papers, and delivered him to Colonel Jameson at North Castle. Arnold, on hearing the news, escaped on board the _Vulture_. André was tried by a court-martial at Tappan, and condemned to death. On the 2d of October he was led to the gallows, and, under the stern code of war, was hanged. [Footnote B: John Paulding, David Williams and Isaac van Wart. Congress afterwards rewarded them with silver medals and pensions for life.] [Illustration: Capture of André.] 13. For several years Holland had favored the Americans; now she began negotiations for a treaty similar to that between France and the United States. Great Britain discovered the purposes of the Dutch government, and remonstrated. On the 20th of December an open declaration of war was made. Thus the Netherlands were added to the enemies of England. CHAPTER XXVII. EVENTS OF 1781. [Sidenote: =Mutiny in the Continental Army.=]