The French wing of the allied armies made up approximately one-half of the total land forces which opposed the British. Commanded by the Count de Rochambeau, it included 7 infantry regiments grouped in 3 brigades. The cavalry was under the Duke de Lauzun and the artillery under Colonel d’Aboville. The French engineers were headed by Colonel Desandrouins and Lieutenant Colonel Querenet, both of whom were instrumental in the preparation of an excellent set of siege plans. [Illustration: _Gen. George Washington, Commander in Chief of the allied French and American forces at Yorktown. (From the Peale portrait in the State House, Annapolis, Md.)_] The third component of the allied armies was the militia, chiefly from Virginia, commanded by Gen. Thomas Nelson, Jr., a native of Yorktown, who was supported by Brig. Gen. George Weedon, Brig. Gen. Robert Lawson, and Brig. Gen. Edward Stevens. INVESTMENT OF YORKTOWN. On September 27 all was in readiness for the movement of the allied armies against the British position at Yorktown and an “Order of Battle” was drawn up. At 5 o’clock in the morning of September 28 the French and American units, on instruction from Washington, their commander in chief, began to move toward Yorktown. The Continentals, followed by the French troops, formed the left column and the militia, the right. The route lay over the principal highways down the peninsula. At the “Halfway House,” midway between Williamsburg and Yorktown, the American regulars moved off to the right, while the French continued on the more direct route. About noon both sections approached Yorktown, and contact was made with British pickets who fell back. Lt. Col. Robert Abercrombie’s Light Infantry, covering the British right, first gave the alarm, and some shots were exchanged with Tarleton’s Legion, which covered the British left, as the American and French troops reached the approaches to Yorktown. By nightfall, the allied units reached temporary positions along Beaverdam Creek within a mile of the main enemy posts. At this point, orders were issued that “The whole army, officers and soldiers, will lay on their arms this night.” The investment of Yorktown, which began so auspiciously on the 28th, was more securely established during the 2 days that followed. On the 29th, the American wing moved more to the east (right) and nearer to the enemy, while both French and American units spread out to their designated campsites, forming a semicircle around Yorktown from the York River on the northwest to Wormley Creek, a tributary of the York, on the south and east. Reconnoitering was extended within cannon range of the enemy’s works, and several skirmishes developed with British patrols. There was also some minor action at Moore’s Dam over Wormley Creek, where the British had thrown up temporary positions. BRITISH POSITION.