The physical strength mentioned by nearly every one who described Washington is so undoubted that the traditions of his climbing the walls of the Natural Bridge, throwing a stone across the Rappahannock at Fredericksburg, and another into the Hudson from the top of the Palisades, pass current more from the supposed muscular power of the man than from any direct evidence. In addition to this, Washington in 1755 claimed to have “one of the best of constitutions,” and again he wrote, “for my own part I can answer, I have a constitution hardy enough to encounter and undergo the most severe trials.” This vigor was not the least reason of Washington’s success. In the retreat from Brooklyn, “for forty-eight hours preceeding that I had hardly been off my horse,” and between the 13th and the 19th of June of 1777 “I was almost constantly on horseback.” After the battle of Monmouth, as told elsewhere, he passed the night on a blanket; the first night of the siege of York “he slept under a mulberry tree, the root serving for a pillow,” and another time he lay “all night in my Great Coat & Boots, in a birth not long enough for me by the head, & much cramped.” Besides the physical strain there was a mental one. During the siege of Boston he wrote that “The reflection on my situation and that of this army, produces many an uneasy hour when all around me are wrapped in sleep.” Humphreys relates that at Newburg in 1783 a revolt of the whole army seemed imminent, and “when General Washington rose from bed on the morning of the meeting, he told the writer his anxiety had prevented him from sleeping one moment the preceeding night.” Washington observed, in a letter written after the Revolution, “strange as it may seem, it is nevertheless true, that it was not until lately I could get the better of my usual custom of ruminating as soon as I awoke in the morning, on the business of the ensuing day; and of my surprise at finding, after revolving many things in my mind that I was no longer a public man, or had any thing to do with public transactions.” Despite his strength and constitution, Washington was frequently the victim of illness. What diseases of childhood he suffered are not known, but presumably measles was among them, for when his wife within the first year of married life had an attack he cared for her without catching the complaint. The first of his known illnesses was “Ague and Feaver, which I had to an extremity” about 1748, or when he was sixteen.