History of Westchester County, New York, Vol. I
The Provincial Congress of this State, which had been in session in New York, adjourned on the 3Uth of June, 1776, to the court-house in White Plains ; and on the 9th of July, while assembled here, the Declaration of Independence was received and read in front of the court-house by John Thomas, Esq.
The battle of White Plains occurred on the 28th of October following. The details of that battle, and of the subsequent burning of the Court-house and the principal dwellings in the village, form part of a chapter which appears elsewhere in this work, written by a masterly hand, and will not be attempted here.
General Howe's retreat from White Plains was mysterious and unaccountable; commanding a magnificent army of veterans, splendidly equipped and Hushed with success, why should he retreat? The question was discussed by Washington and his council of officers without arriving at any satisfactory answer.
AVhen Howe returned to England his conduct here was investigated by a committee of Parliament, but he refused to explain I'urther than to say that he "had political reasons." The question remained unanswered until tlfe publication, in 1879, by that laborious historian, Edward F. de Lancey, of " The History of New York during the Revolutionary War, by Thomas Jones," in which it appears that one William Demont, the adjutant of Colonel Magaw, the commander of Fort Washington, on New York Island, on the 2d day of November, 1776, passed undiscovered out of the fort and into the camp of Lord Percy, at Harlem, carrying with him plans of Fort Washington and full information as to the garrison, and placed them in the hands of the British officer. Percy, of course, sent the information to Lord Howe at White Plains ; the latter suddenly changed his plan of attacking Washington, and on the 4th of November prepared to march to Fort Washington, which he captured on the 16th of that month.