Many of the citizens of Philadelphia must remember Mrs. Sarah Kemp, who died in Race street, in 1820, at the advanced age of eighty-four years. Andrew Kemp, the only son of this respectable matron, entered the American army, almost at the very commencement of the struggle, and before, as his mother has often informed me, he had reached his majority. As he shall be my first witness against General Reed, it is proper to make the reader well acquainted with him. His gallantry, and a personal service which he had the good fortune to render to one of General Washingston's[TN] immediate staff, soon promoted him from the ranks, and he fought with great bravery, at the battles of White Plains, Trenton, Princeton, Brandywine, Germantown and Monmouth. Sergeant Kemp was one of the garrison of Fort Mercer, under the command of Colonel Greene, when that fortress was assailed in the autumn of 1777, by the Hessian troops, commanded by Colonel Donop. In this affair, which, though not one of the most remarkable, was one of the most brilliant of the Revolution, Sergeant Kemp particularly distinguished himself, and was wounded slightly in the arm, and severely in the left thigh by a musket ball: at the subsequent capture of Fort Mercer by Cornwallis, Kemp was one of the few who fell into the hands of the enemy--the remainder of the garrison succeeding in safely evacuating the fort. In a few weeks, he managed to effect his escape from Howe's winter quarters at Philadelphia, and immediately joined the American army at Valley Forge. The privations of that encampment, dreadfully aggravated the sufferings of poor Kemp; but, after languishing during the season in one of the military hospitals, he resumed active service in the spring, and served in May under Lafayette at the affair of Barren Hill. At the battle of Monmouth, he fought with his usual intrepidity, but the fatigues of the engagement renewed the affection of his imperfectly healed leg; and, about three weeks after, he was obliged to submit to its amputation. Upon leaving the army, he received from General Washington himself a certificate of conduct and character, which I copy from the original before me. _Head Quarters, June 23, 1778._ Sergeant Andrew Kemp is personally known to me as a brave and faithful soldier, who has served in several engagements, and who desires his discharge only in consequence of the loss of a limb, which unfits him for further service. His dutiful conduct is reported to me to be equal to his bravery; and he retires from the army with my good opinion and that of all whom I have heard speak of him. (Signed,) G. WASHINGTON.