This lady, a resident of Massachusetts, had early in the war been bereaved of her husband and only child, not by the vicissitudes of the battle-field but by sickness at home, and her heart worn with grief, sought relief, where it was most likely to find it, in ministering to the sufferings of others.

She accepted an appointment under Miss Dix as a hospital nurse, and commenced her hospital life in Frederick City, Maryland, in March, 1862, where she was entrusted with the care of a large number of wounded from the first battle of Winchester. Her life here passed without much of special interest, till September, 1862, when the little Maryland city was filled for two or three days with Stonewall Jackson's Corps on their way to South Mountain and Antietam. The rebels took possession of the hospital, and filled it for the time with their sick and wounded men. Resistance was useless, and Mrs. McKay treated the rebel officers and men courteously, and did what she could for the sick; her civility and kindness were recognized, and she was treated with respect by all. After the battle of Antietam, Frederick City and its hospitals were filled with the wounded, and Mrs. McKay's heart and hands were full—but as soon as the wounded became convalescent, she went to Washington and was assigned to duty for a time in the hospitals of the Capital. In January, she went to Falmouth and found employment as a nurse in the Third Corps Hospital. Here by her skill and tact she soon effected a revolution, greatly to the comfort of the poor fellows in the hospital. From being the worst it became the best of the corps hospitals at the front. General Birney and his excellent wife, seconded and encouraged all her efforts for its improvement.

The battles which though scattered over a wide extent of territory, and fought at different times and by different portions of the contending forces, have yet been known under the generic name of Chancellorsville, were full of horrors for Mrs. McKay. She witnessed the bloody but successful assault on Marye's Heights, and while ministering to the wounded who covered all the ground in front of the fortified position, received the saddening intelligence that her brother, who was with Hooker at Chancellorsville, had been instantly killed in the protracted fighting there. Other of her friends too had fallen, but crushing the agony of her own loss back into her heart, she went on ministering to the wounded. Six weeks later she was in Washington, awaiting the battle between Lee's forces and Hooker's, afterwards commanded by General Meade. When the intelligence of the three days' conflict at Gettysburg came, she went to Baltimore, and thence by such conveyance as she could find, to Gettysburg, reaching the hospital of her division, five miles from Gettysburg, on the 7th of July. Here she remained for nearly two months, laboring zealously for the welfare of a thousand or fifteen hundred wounded men. In the autumn she again sought the hospital of the Third Division, Third Corps, at the front, which for the time was at Warrenton, Virginia. After the battle of Mine Run, she had ample employment in the care of the wounded; and later in the season she had charge of one of the hospitals at Brandy Station. Like the other ladies who were connected with hospitals at this place, she was compelled to retire by the order of April 15th; but like them she returned to her work early in May, at Belle Plain, Fredericksburg, White House, and City Point, where she labored with great assiduity and success. The changes in the army organization in June, 1864, removed most of her friends in the old third corps, and Mrs. McKay, on the invitation of the surgeon in charge of the cavalry corps hospital, took charge of the special diet of that hospital, where she remained for nearly a year, finally leaving the service in March, 1865, and remaining in Virginia in the care and instruction of the freedmen till late in the spring of 1866. The officers and men who had been under her care in the Cavalry Corps Hospital, presented her on Christmas day, 1864, with an elegant gold badge and chain, with a suitable inscription, as a testimonial of their gratitude for her services. She had previously received from the officers of the Seventeenth Maine Volunteers, whom she had cared for after the battle of Chancellorsville, a magnificent Kearny Cross, with its motto and an inscription indicating by whom it was presented.