On July 3, 1775, George Washington arrived at Cambridge, near Boston, and took command of an army of about 17,000 men that faced a British army occupying Boston. Washington devoted his energies to organizing and training his motley force during the ensuing fall and winter, the enemy making no decided move to drive him off. Finally, on March 4, 1776, having conceived a plan that promised success to him, he suddenly seized and fortified Dorchester Heights, about two miles south of Boston, from which he could command the whole of Boston and the channel south of it, by means of guns which he had ordered, to be dragged through the snow from Ticonderoga. His plan worked perfectly; for the British General Howe, after a vain attempt to drive Washington away, evacuated Boston himself, and took his army to Halifax. This was Washington's opening move in our War of the Revolution. It was the execution of a plan admirably conceived. There may seem little of originality or brilliancy in it to us now, looking at a map of Boston in the quiet and safety of a library, but there must have been a great deal of merit and originality in it; for it took a British major-general completely by surprise, and compelled him to evacuate an important stronghold with a precipitancy that must have been distinctly galling to British pride. Few neater feats of strategy can be found in military history. Washington's next feat was in extricating his force from a distinctly perilous position in Brooklyn in front of a superior British force, retreating across the East River to New York, and landing near what is now called Fulton Street. This was on August 30, 1776. The next three months were spent in maneuvers that showed great clearness in conception and great energy in execution on Washington's part, and ended with his occupying Trenton, and Howe occupying New York with the bulk of his forces. Washington had only a little more than 4,000 men, while Howe had 30,000. Washington's troops were discouraged, half-ragged, underfed and untrained; Howe's were elated, well clad, well fed and thoroughly trained. Washington was in as dangerous a plight as can easily be imagined. He extricated himself by conceiving and carrying into execution the brilliant plan of crossing the Delaware River on Christmas night, forcing his way through floating ice, and falling on the amazed camp of the Hessians on the other side. His invention worked perfectly, and effected almost a complete reversal in the relative conditions of the opposing forces; for it put the British on the defensive, and made them withdraw all their forces from New Jersey.