One express after another brought Washington word of these occurrences. First, he sent off a party of rifle and artillery men, with two twelve-pounders, to secure the new ships which had run aground at Yonkers. Next, he ordered Colonel Sargent to march up along the eastern shore with five hundred infantry, a troop of light-horse, and a detachment of artillery, to prevent the landing of the enemy. Before the troops arrived at Dobbs’ Ferry the ships’ boats had plundered a store there, and set it on fire. To prevent, if possible, the men-of-war already up the river from coming down, or others from below joining them, Washington gave orders to complete the obstructions. Two hulks which lay in Spyt den Duivel Creek, were hastily ballasted by men from General Heath’s division, and men were sent up to get off the ships which had run aground at Philips’ Mills, that they might be brought down and sunk immediately. It is difficult to give an idea of the excitement caused by this new irruption of hostile ships into the waters of the Hudson, or of the various conjectures as to their object. They might intend merely to interrupt navigation, and prevent supplies from coming down to the American army. They might be carrying arms and ammunition for domestic enemies skulking about the river, and only waiting an opportunity to strike a blow. They might have troops concealed on board with intent to surprise the posts in the Highlands, and cut off the intercourse between the American armies. To such a degree had the spirit of disaffection been increased in the counties adjacent to the river, since the descent of the Rose and Phœnix, by the retreats and evacuation which had taken place; and so great had been the drain on the militia of those counties for the army of Washington, that, in case of insurrection, those who remained at home and were well-affected, would be outnumbered, and might easily be overpowered, especially with the aid of troops landed from ships. While this agitation prevailed below, fugitive river crafts carried the news up to the Highlands that the frigates were already before Tarrytown in the Tappan Sea. Word was instantly despatched to Peter R. Livingston, president of the Provincial Congress, and startled that deliberative body, which was then seated at Fishkill just above the Highlands. The committee of safety wrote, on the spur of the moment, to Washington. “Nothing,” say they, “can be more alarming than the present situation of our State. We are daily getting the most authentic intelligence of bodies of men enlisted and armed in order to assist the enemy. We much fear that they, co-operating with the enemy, may seize such passes as will cut off the communication between the army and us, and prevent your supplies. * * * * We beg leave to suggest to your Excellency the propriety of sending a body of men to the Highlands or Peekskill, to secure the passes, prevent insurrection, and overawe the disaffected.”