Pennypacker's Mills is delightfully situated in the angle formed by the union of the two forks of the Perkiomen, the largest tributary of the Schuylkill. Hans Joest Heijt, who built the grist mill and house on the land in 1720, sold the property in 1730 to John Pauling. He was succeeded in 1757 by Peter Pannebecker. His son Samuel was the owner of the house by the creek when, on September 26, 1777, Washington reached the Mills.
The orderly book of the following days and letters written from the house shed light on the events of the stay here.
On the day he reached the Mills, Washington wrote to William Henry at Lancaster:
"You are hereby authorized to impress all the Blankets, Shoes, Stockings, and other Articles of Clothing that can be spared by the Inhabitants of the County of Lancaster, for the Use of the Continental Army, paying for the same at reasonable Rates or giving Certificates."
The entry in the orderly book on September 28 read:
"The Commander-in-Chief has the happiness again to congratulate the army on the success of the Americans to the Northward. On the 19th inst. an engagement took place between General Burgoyne's army and the left wing of ours, under General Gates. The battle began at 10 o'clock, and lasted till night—our troops fighting with the greatest bravery, not giving an inch of ground.... To celebrate this success the General orders that at 4 o'clock this afternoon all the troops be paraded and served with a gill of rum per man, and that at the same time there be discharges of 13 pieces of artillery from the park."
On the same day there was a council of war. It was found that there were in camp, fit for duty, 5,472 men. The whole army in all the camps then contained about eight thousand Continental troops and three thousand militia.
Next day Washington wrote:
"I shall move the Army four or five miles lower down to-day from whence we may reconnoitre and fix upon a proper situation, at such distance from the Enemy, as will entitle us to make an attack, should we see a proper opening, or stand upon the defensive till we obtain further reinforcements...."
Later in the day the army marched to Skippack, within about twenty-five miles of Philadelphia. The next stage in the advance was Methacton Hill, and from there the army began to move, on October 3, at seven o'clock in the evening, to the attack on the British at Germantown.