Excerpts from Books and Wikipedia
"The Newburgh Conspiracy was what appeared to be a planned military coup by the Continental Army in March 1783, when the American Revolutionary War was at its end. . . . Soldiers were unhappy that they had not been paid for some time and that pensions that had been promised remained unfunded. The letter suggested that they should take unspecified action against Congress to resolve the issue. . . . Washington then gave a short but impassioned speech, now known as the Newburgh Address, counseling patience. His message was that they should oppose anyone "who wickedly attempts to open the floodgates of civil discord and deluge our rising empire in blood." He then produced a letter from a member of Congress to read to the officers. He gazed upon it and fumbled with it without speaking. He then took a pair of reading glasses from his pocket, which were new; few of the men had seen him wear them. He then said: 'Gentlemen, you will permit me to put on my spectacles, for I have not only grown gray but almost blind in the service of my country." This caused the men to realize that Washington had sacrificed a great deal for the Revolution, just as much as any of them. These, of course, were his fellow officers, most having worked closely with him for several years. Many of those present were moved to tears, and with this act, the conspiracy collapsed as he read the letter." [Wikipedia]